CONSOLIDATED BALANCE SHEETS (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009
Current assets:
Cash and cash equivalents	$ 230.7	$ 148.5
Accounts receivable, net of allowance for doubtful accounts of $149.2 and $173.1 at December 31, 2010 and 2009, respectively	655.6	574.2
Supplies inventories	103.4	90.0
Prepaid expenses and other	95.7	80.1
Deferred income taxes	58.4	42.8
Total current assets	1,143.8	935.6
Property, plant and equipment, net	586.9	500.8
Goodwill, net	2,601.3	1,897.1
Intangible assets, net	1,674.1	1,342.2
Joint venture partnerships and equity method investments	78.5	71.4
Other assets, net	103.2	90.7
Total assets	6,187.8	4,837.8
Current liabilities:
Accounts payable	257.8	183.1
Accrued expenses and other	352.9	275.7
Noncontrolling interest	148.1	142.4
Short-term borrowings and current portion of long-term debt	361.7	417.2
Total current liabilities	1,120.5	1,018.4
Long-term debt, less current portion	1,826.7	977.2
Deferred income taxes and other tax liabilities	602.3	577.7
Other liabilities	151.4	158.4
Total liabilities	3,700.9	2,731.7
Commitments and contingent liabilities
Noncontrolling interest	20.6	0
Shareholders' equity
Common stock, 102.4 and 105.3 shares outstanding at December 31, 2010 and 2009, respectively	12.2	12.5
Additional paid-in capital	53.9	36.7
Retained earnings	3,246.6	2,927.9
Less common stock held in treasury	(934.9)	(932.5)
Accumulated other comprehensive income	88.5	61.5
Total shareholders' equity	2,466.3	2,106.1
Total liabilities and shareholders' equity	$ 6,187.8	$ 4,837.8

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Millions, unless otherwise specified	Dec. 31, 2010	Dec. 31, 2009
Current assets:
Allowance for doubtful accounts	$ 149.2	$ 173.1
Shareholders' equity
Common stock, shares outstanding (in shares)	102.4	105.3

CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Income Statement [Abstract]
Net sales	$ 5,003.9	$ 4,694.7	$ 4,505.2
Cost of sales	2,906.1	2,723.8	2,631.4
Gross profit	2,097.8	1,970.9	1,873.8
Selling, general and administrative expenses	1,034.3	958.9	935.1
Amortization of intangibles and other assets	72.7	62.6	57.9
Restructuring and other special charges	12.0	13.5	37.9
Operating income	978.8	935.9	842.9
Other income (expenses):
Interest expense	(70.0)	(62.9)	(72.0)
Equity method income, net	10.6	13.8	14.4
Investment income	1.1	1.6	2.5
Other, net	(4.9)	(3.8)	(2.1)
Earnings before income taxes	915.6	884.6	785.7
Provision for income taxes	344.0	329.0	307.9
Net earnings	571.6	555.6	477.8
Less: Net earnings attributable to the noncontrolling interest	(13.4)	(12.3)	(13.3)
Net earnings attributable to Laboratory Corporation of America Holdings	$ 558.2	$ 543.3	$ 464.5
Basic earnings per common share (in dollars per share)	$ 5.42	$ 5.06	$ 4.23
Diluted earnings per common share (in dollars per share)	$ 5.29	$ 4.98	$ 4.16

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (USD $) In Millions, unless otherwise specified	Total	Common stock	Additional Paid-in Capital	Retained Earnings	Treasury stock	Accumulated Other Comprehensive Income (Loss)
BALANCE at Dec. 31, 2007	$ 1,725.3	$ 13.2	$ 460.9	$ 2,028.3	$ (897.1)	$ 120.0
Comprehensive earnings:
Net earnings attributable to Laboratory Corporation of America Holdings	464.5	0	0	464.5	0	0
Other comprehensive earnings:
Foreign currency translation adjustments	(129.6)	0	0	0	0	(129.6)
Interest rate swap adjustments	(13.5)	0	0	0	0	(13.5)
Net benefit plan adjustments	(81.0)	0	0	0	0	(81.0)
Tax effect of other comprehensive earnings adjustments	87.4	0	0	0	0	87.4
Comprehensive earnings	327.8
Issuance of common stock under employee stock plans	64.4	0.1	64.3	0	0	0
Surrender of restricted stock awards	(32.7)	0	0	0	(32.7)	0
Conversion of zero-coupon convertible debt	0.1	0	0.1	0	0	0
Stock compensation	36.2	0	36.2	0	0	0
Value of noncontrolling interest put	(123.0)	0	(123.0)	0	0	0
Income tax benefit from stock options exercised	20.8	0	20.8	0	0	0
Purchase of common stock	(330.6)	(0.5)	(221.9)	(108.2)	0	0
BALANCE at Dec. 31, 2008	1,688.3	12.8	237.4	2,384.6	(929.8)	(16.7)
Comprehensive earnings:
Net earnings attributable to Laboratory Corporation of America Holdings	543.3	0	0	543.3	0	0
Other comprehensive earnings:
Foreign currency translation adjustments	93.3	0	0	0	0	93.3
Interest rate swap adjustments	2.9	0	0	0	0	2.9
Net benefit plan adjustments	31.5	0	0	0	0	31.5
Tax effect of other comprehensive earnings adjustments	(49.5)	0	0	0	0	(49.5)
Comprehensive earnings	621.5
Issuance of common stock under employee stock plans	24.8	0	24.8	0	0	0
Surrender of restricted stock awards	(2.7)	0	0	0	(2.7)	0
Conversion of zero-coupon convertible debt	11.4	0.1	11.3	0	0	0
Stock compensation	36.4	0	36.4	0	0	0
Income tax benefit from stock options exercised	(0.1)	0	(0.1)	0	0	0
Purchase of common stock	(273.5)	(0.4)	(273.1)	0	0	0
BALANCE at Dec. 31, 2009	2,106.1	12.5	36.7	2,927.9	(932.5)	61.5
Comprehensive earnings:
Net earnings attributable to Laboratory Corporation of America Holdings	558.2	0	0	558.2	0	0
Other comprehensive earnings:
Foreign currency translation adjustments	41.3	0	0	0	0	41.3
Interest rate swap adjustments	8.2	0	0	0	0	8.2
Net benefit plan adjustments	(8.3)	0	0	0	0	(8.3)
Tax effect of other comprehensive earnings adjustments	(14.2)	0	0	0	0	(14.2)
Comprehensive earnings	585.2
Issuance of common stock under employee stock plans	83.4	0.2	83.2	0	0	0
Surrender of restricted stock awards	(2.4)	0	0	0	(2.4)	0
Conversion of zero-coupon convertible debt	1.1	0	1.1	0	0	0
Stock compensation	40.0	0	40.0	0	0	0
Value of noncontrolling interest put		0	(17.2)	0	0	0
Income tax benefit from stock options exercised	7.6	0	7.6	0	0	0
Purchase of common stock	(337.5)	(0.5)	(97.5)	(239.5)	0	0
BALANCE at Dec. 31, 2010	$ 2,466.3	$ 12.2	$ 53.9	$ 3,246.6	$ (934.9)	$ 88.5

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
CASH FLOWS FROM OPERATING ACTIVITIES:
Net earnings	$ 571.6	$ 555.6	$ 477.8
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	203.6	195.1	179.7
Stock compensation	40.0	36.4	36.2
Loss on sale of assets	4.1	2.6	1.1
Accreted interest on zero-coupon subordinated notes	5.8	8.3	11.3
Cumulative earnings less than (in excess of) distribution from equity method investments	6.3	2.2	(0.6)
Deferred income taxes	12.9	9.6	69.6
Change in assets and liabilities (net of effects of acquisitions):
(Increase) decrease in accounts receivable (net)	(25.3)	74.0	28.0
Increase in inventories	(5.8)	(4.3)	(8.6)
(Increase) decrease in prepaid expenses and other	(13.5)	5.9	(15.1)
Increase in accounts payable	50.1	22.8	15.9
Increase (decrease) in accrued expenses and other	33.8	(45.8)	(14.4)
Net cash provided by operating activities	883.6	862.4	780.9
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(126.1)	(114.7)	(156.7)
Proceeds from sale of assets	4.8	0.9	0.5
Deferred payments on acquisitions	(4.5)	(3.3)	(4.1)
Purchases of short-term investments	0	0	(72.8)
Proceeds from sale of short-term investments	0	0	182.7
Acquisition of licensing technology	(0.4)	0	(0.8)
Investments in equity affiliates	(10.0)	(4.3)	0
Acquisition of businesses, net of cash acquired	(1,181.3)	(212.6)	(344.8)
Net cash used for investing activities	(1,317.5)	(334.0)	(396.0)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from senior notes offerings	925.0	0	0
Proceeds from revolving credit facilities	160.0	4.2	145.2
Payments on revolving credit facilities	(235.0)	0	(74.4)
Principal payments on term loan	(50.0)	(50.0)	(25.0)
Payments on zero-coupon subordinated notes	(11.4)	(289.4)	(2.1)
Payments on vendor-financed equipment	(1.3)	(1.5)	0
Increase (decrease) in bank overdraft	0	(5.0)	5.0
Payments on long-term debt	(0.1)	(0.1)	(0.1)
Payment of debt issuance costs	(9.7)	(0.1)	(0.1)
Proceeds from sale of interest in a consolidated subsidiary	137.5	0	0
Cash paid to acquire an interest in a consolidated subsidiary	(137.5)	0	0
Noncontrolling interest distributions	(12.6)	(11.3)	(14.0)
Excess tax benefits from stock based compensation	5.1	0.5	16.2
Net proceeds from issuance of stock to employees	83.4	24.8	64.4
Purchase of common stock	(338.1)	(273.0)	(333.6)
Net cash provided by (used for) financing activities	515.3	(600.9)	(218.5)
Effect of exchange rate changes on cash and cash equivalents	0.8	1.3	(3.1)
Net increase (decrease) in cash and cash equivalents	82.2	(71.2)	163.3
Cash and cash equivalents at beginning of period	148.5	219.7	56.4
Cash and cash equivalents at end of period	$ 230.7	$ 148.5	$ 219.7

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Summary of Significant Accounting Policies

1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Financial Statement Presentation:

Laboratory Corporation of America Holdings with its subsidiaries (the “Company”) is the second largest independent clinical laboratory company in the United States based on 2010 net revenues. Through a national network of laboratories, the Company offers a broad range of testing services used by the medical profession in routine testing, patient diagnosis, and in the monitoring and treatment of disease. In addition, the Company has developed specialty and niche operations based on certain types of specialized testing capabilities and client requirements, such as oncology testing, HIV genotyping and phenotyping, diagnostic genetics and clinical research trials.

Since its founding in 1971, the Company has grown into a network of 51 primary laboratories and over 1,700 patient service centers along with a network of branches and STAT laboratories. With over 31,000 employees, the Company processes tests on more than 440,000 patient specimens daily and provides clinical laboratory testing services in all 50 states, the District of Columbia, Puerto Rico, Belgium and three provinces in Canada. The Company operates within one reportable segment based on the way the Company manages its business.

The consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries for which it exercises control. Long-term investments in affiliated companies in which the Company exercises significant influence, but which it does not control, are accounted for using the equity method. Investments in which the Company does not exercise significant influence (generally, when the Company has an investment of less than 20% and no representation on the investee's board of directors) are accounted for using the cost method. All significant inter-company transactions and accounts have been eliminated. The Company does not have any variable interest entities or special purpose entities whose financial results are not included in the consolidated financial statements.

The financial statements of the Company's foreign subsidiaries are measured using the local currency as the functional currency. Assets and liabilities are translated at exchange rates as of the balance sheet date. Revenues and expenses are translated at average monthly exchange rates prevailing during the year. Resulting translation adjustments are included in "Accumulated other comprehensive income.”

Revenue Recognition:

Sales are recognized on the accrual basis at the time test results are reported, which approximates when services are provided. Services are provided to certain patients covered by various third-party payer programs including various managed care organizations, as well as the Medicare and Medicaid programs. Billings for services under third-party payer programs are included in sales net of allowances for contractual discounts and allowances for differences between the amounts billed and estimated program payment amounts. Adjustments to the estimated payment amounts based on final settlement with the programs are recorded upon settlement as an adjustment to revenue. In 2010, 2009 and 2008, approximately 19.4%, 19.1% and 17.7%, respectively, of the Company's revenues were derived directly from the Medicare and Medicaid programs. The Company has capitated agreements with certain managed care customers and recognizes related revenue based on a predetermined monthly contractual rate for each member of the managed care plan regardless of the number or cost of services provided by the Company. In 2010, 2009 and 2008, approximately 3.1%, 3.6% and 4.0%, respectively, of the Company's revenues were derived from such capitated agreements.

In connection with revenue arrangements with multiple deliverables, revenue is deferred until the Company can reasonably estimate when the performance obligation ceases or becomes inconsequential.

Use of Estimates:

The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reported periods. Significant estimates include the allowances for doubtful accounts, deferred tax assets, fair values and amortization lives for intangible assets and accruals for self-insurance reserves and pensions. The allowance for doubtful accounts is determined based on historical collections trends, the aging of accounts, current economic conditions and regulatory changes. Actual results could differ from those estimates.

Concentration of Credit Risk:

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable.

The Company maintains cash and cash equivalents with various major financial institutions. The total cash balances on deposit that exceeded the balances insured by the F.D.I.C., were approximately $52.2 at December 31, 2010. Cash equivalents at December 31, 2010, totaled $177.4, which includes amounts invested in money market funds, time deposits, municipal, treasury and government funds.

Substantially all of the Company’s accounts receivable are with companies in the health care industry and individuals. However, concentrations of credit risk are limited due to the number of the Company’s clients as well as their dispersion across many different geographic regions.

Accounts receivable balances (gross) from Medicare and Medicaid were $125.0 and $106.4 at December 31, 2010 and 2009, respectively.

Earnings per Share:

Basic earnings per share is computed by dividing net earnings, less preferred stock dividends and accretion, by the weighted average number of common shares outstanding. Diluted earnings per share is computed by dividing net earnings including the impact of dilutive adjustments by the weighted average number of common shares outstanding plus potentially dilutive shares, as if they had been issued at the earlier of the date of issuance or the beginning of the period presented. Potentially dilutive common shares result primarily from the Company’s outstanding stock options, restricted stock awards, performance share awards, and shares issuable upon conversion of zero-coupon subordinated notes.

The following represents a reconciliation of basic earnings per share to diluted earnings per share:

	2010						2009						2008
					Per Share						Per Share						Per Share
	Income		Shares		Amount		Income		Shares		Amount		Income		Shares		Amount
Basic earnings per share	$	558.2		103.0	$	5.42	$	543.3		107.4	$	5.06	$	464.5		109.7	$	4.23
Stock options		--		0.6				--		0.5				--		0.7
Restricted stock awards and other		--		0.3				--		0.2				--		0.3
Effect of convertible debt, net of tax		--		1.5				--		1.0				--		1.1
Diluted earnings per share	$	558.2		105.4	$	5.29	$	543.3		109.1	$	4.98	$	464.5		111.8	$	4.16

The following table summarizes the potential common shares not included in the computation of diluted earnings per share because their impact would have been antidilutive:

	Years Ended December 31,
	2010		2009		2008
Stock options		2.7		4.6		2.4

Stock Compensation Plans:

The Company measures stock compensation cost for all equity awards at fair value on the date of grant and recognizes compensation expense over the service period for awards expected to vest. The fair value of restricted stock awards and performance shares is determined based on the number of shares granted and the quoted price of the Company’s common stock on grant date. Such value is recognized as expense over the service period, net of estimated forfeitures. The estimation of equity awards that will ultimately vest requires judgment and the Company considers many factors when estimating expected forfeitures, including types of awards, employee class, and historical experience. The cumulative effect on current and prior periods of a change in the estimated forfeiture rate is recognized as compensation cost in earnings in the period of the revision. Actual results and future estimates may differ substantially from the Company’s current estimates.

See note 14 for assumptions used in calculating compensation expense for the Company’s stock compensation plans.

Cash Equivalents:

Cash equivalents (primarily investments in money market funds, time deposits, municipal, treasury and government funds which have original maturities of three months or less at the date of purchase) are carried at cost which approximates market.

Inventories:

Inventories, consisting primarily of purchased laboratory and client supplies, are stated at the lower of cost (first-in, first-out) or market.

Property, Plant and Equipment:

Property, plant and equipment are recorded at cost. The cost of properties held under capital leases is equal to the lower of the net present value of the minimum lease payments or the fair value of the leased property at the inception of the lease. Depreciation and amortization expense is computed on all classes of assets based on their estimated useful lives, as indicated below, using principally the straight-line method.

	Years
Buildings and building improvements		35
Machinery and equipment		3-10
Furniture and fixtures		5-10

Leasehold improvements and assets held under capital leases are amortized over the shorter of their estimated useful lives or the term of the related leases. Expenditures for repairs and maintenance are charged to operations as incurred. Retirements, sales and other disposals of assets are recorded by removing the cost and accumulated depreciation from the related accounts with any resulting gain or loss reflected in the consolidated statements of operations.

Capitalized Software Costs:

The Company capitalizes purchased software which is ready for service and capitalizes software development costs incurred on significant projects starting from the time that the preliminary project stage is completed and management commits to funding a project until the project is substantially complete and the software is ready for its intended use. Capitalized costs include direct material and service costs and payroll and payroll-related costs. Research and development costs and other computer software maintenance costs related to software development are expensed as incurred. Capitalized software costs are amortized using the straight-line method over the estimated useful life of the underlying system, generally five years.

Long-Lived Assets:

Goodwill is evaluated for impairment by applying a fair value based test on an annual basis and more frequently if events or changes in circumstances indicate that the asset might be impaired.

Long-lived assets, other than goodwill, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amounts may not be recoverable. Recoverability of assets to be held and used is determined by the Company at the level for which there are identifiable cash flows by comparison of the carrying amount of the assets to future undiscounted net cash flows before interest expense and income taxes expected to be generated by the assets. Impairment, if any, is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets (based on market prices in an active market or on discounted cash flows). Assets to be disposed of are reported at the lower of the carrying amount or fair value. The Company completed an annual impairment analysis of its indefinite lived assets, including goodwill, and has found no instances of impairment as of December 31, 2010.

Intangible Assets:

Intangible assets (patents and technology, customer relationships and non-compete agreements), are amortized on a straight-line basis over the expected periods to be benefited, such as legal life for patents and technology, 10 to 25 years for customer lists and contractual lives for non-compete agreements.

Debt Issuance Costs:

The costs related to the issuance of debt are capitalized and amortized to interest expense using the effective interest method over the terms of the related debt.

Professional Liability:

The Company is self-insured (up to certain limits) for professional liability claims arising in the normal course of business, generally related to the testing and reporting of laboratory test results. The Company estimates a liability that represents the ultimate exposure for aggregate losses below those limits. The liability is discounted and is based on a number of assumptions and factors for known and incurred but not reported claims based on actuarial assessment of the accrual driven by frequency and amount of claims.

Income Taxes:

The Company accounts for income taxes utilizing the asset and liability method. Under this method deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and for tax loss carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company does not recognize a tax benefit, unless the Company concludes that it is more likely than not that the benefit will be sustained on audit by the taxing authority based solely on the technical merits of the associated tax position. If the recognition threshold is met, the Company recognizes a tax benefit measured at the largest amount of the tax benefit that the Company believes is greater than 50% likely to be realized. The Company records interest and penalties in income tax expense.

Derivative Financial Instruments:

Interest rate swap agreements, which are currently being used by the Company in the management of interest rate exposure, are accounted for at fair value. The Company’s zero-coupon subordinated notes contain two features that are considered to be embedded derivative instruments under authoritative guidance in connection with accounting for derivative instruments and hedging activities. The Company believes these embedded derivatives had no fair value at December 31, 2010 and 2009.

See note 18 for the Company’s objectives in using derivative instruments and the effect of derivative instruments and related hedged items on the Company’s financial position, financial performance and cash flows.

Fair Value of Financial Instruments:

Fair value measurements for financial assets and liabilities are determined based on the assumptions that a market participant would use in pricing an asset or liability. A three-tiered fair value hierarchy draws distinctions between market participant assumptions based on (i) observable inputs such as quoted prices in active markets (Level 1), (ii) inputs other than quoted prices in active markets that are observable either directly or indirectly (Level 2) and (iii) unobservable inputs that require the Company to use present value and other valuation techniques in the determination of fair value (Level 3).

On January 1, 2009, the Company adopted, on a prospective basis, authoritative guidance related to fair value measurements pertaining to nonfinancial assets and liabilities that are remeasured at fair value on a non-recurring basis. This guidance established the authoritative definition of fair value, set out a framework for measuring fair value and expanded the required disclosures about fair value measurement. For more information, see note 17.

Research and Development:

The Company expenses research and development costs as incurred.

New Accounting Pronouncements:

In June 2009, the FASB issued authoritative guidance in connection with adding qualified special purpose entities into the scope of guidance for consolidation of variable interest entities. This literature also modifies the analysis by which a controlling interest of a variable interest entity is determined thereby requiring the controlling interest to consolidate the variable interest entity. A controlling interest exists if a party to a variable interest entity has both (i) the power to direct the activities of a variable interest entity that most significantly impact the entity’s economic performance and (ii) the obligation to absorb losses of or receive benefits from the entity that could be potentially significant to the variable interest entity. The guidance became effective in 2010. The adoption of the authoritative guidance did not have an impact on the Company’s consolidated financial statements as of and for the year ended December 31, 2010.

BUSINESS ACQUISITIONS	12 Months Ended
BUSINESS ACQUISITIONS	Dec. 31, 2010
Notes To Financial Statements [Abstract]
Business Acquisitions	2. BUSINESS ACQUISITIONS On December 1, 2010, the Company acquired Genzyme Genetics, a business unit of Genzyme Corporation, for approximately $925.2 in cash (net of cash acquired). The Genzyme Genetics acquisition was made to expand the Company’s capabilities in reproductive, genetic, hematology-oncology and clinical trials central laboratory testing, enhance the Company’s esoteric testing capabilities and advance the Company’s personalized medicine strategy. The Genzyme Genetics purchase consideration has been allocated to the estimated fair market value of the net assets acquired, including approximately $279.6 in identifiable intangible assets (primarily customer relationships and trade name) with weighted-average useful lives of approximately 23 years; and residual amount of goodwill of approximately $537.8. Approximately $810.5 of the total intangible value will be amortizable for tax purposes over 15 years. On October 28, 2010, in conjunction with the acquisition of Genzyme Genetics, the Company entered into a $925.0 bridge term loan credit agreement. The Company replaced and terminated the bridge term loan credit agreement in November 2010 by making an offering in the debt capital markets. On November 19, 2010, the Company sold $925.0 in debt securities, consisting of $325.0 aggregate principal amount of 3.125% Senior Notes due May 15, 2016 and $600.0 aggregate principal amount of 4.625% Senior Notes due November 15, 2020. As of December 31, 2010 the Company incurred $7.0 of financing commitment fees, which is included in interest expense for the year ended December 31, 2010. The Company incurred approximately $25.7 in professional fees and expenses in connection with the acquisition of Genzyme Genetics and other acquisition activity, including significant costs associated with the Federal Trade Commission’s review of the Company’s purchase of specified net assets of Westcliff Medical Laboratories, Inc. These fees and expenses are included in selling, general and administrative expenses for the year ended December 31, 2010. During the year ended December 31, 2010, the Company also acquired various laboratories and related assets for approximately $256.1 in cash (net of cash acquired). These acquisitions were made primarily to extend the Company’s geographic reach in important market areas and/or enhance the Company’s scientific differentiation and esoteric testing capabilities. During the year ended December 31 2009, the Company acquired various other laboratories and related assets for approximately $212.6 in cash (net of cash acquired). The acquisition activity primarily included the acquisition of Monogram Biosciences, Inc. (“Monogram”) effective August 3, 2009 for approximately $160.0 in cash (net of cash acquired). The Monogram acquisition was made to enhance the Company’s scientific differentiation and esoteric testing capabilities and advance the Company’s personalized medicine strategy. The Monogram purchase consideration has been allocated to the estimated fair market value of the net assets acquired, including approximately $63.5 in identifiable intangible assets (primarily non-tax deductible customer relationships, patents and technology, and trade name) with weighted-average useful lives of approximately 15 years; net operating loss tax assets of approximately $44.8, which are expected to be realized over a period of 18 years; and residual amount of non-tax deductible goodwill of approximately $83.6. Monogram has an active research and development department, which is primarily focused on the development of oncology and infectious disease technology. As a result of this acquisition, the Company incurred approximately $12.1 and $5.2 of research and development expenses (included in selling, general and administrative expenses) for the years ended December 31, 2010 and 2009, respectively. In connection with the Monogram acquisition, the Company incurred approximately $2.7 in transaction fees and expenses (included in selling, general and administrative expenses) for the year ended December 31, 2009. During the year ended December 31, 2008, the Company acquired various laboratories and related assets for approximately $203.9 in cash (net of cash acquired). These acquisitions were made primarily to extend the Company’s geographic reach in important market areas or acquire scientific differentiation and esoteric testing capabilities. Effective January 1, 2008 the Company acquired additional partnership units in its Ontario, Canada (“Ontario”) joint venture for approximately $140.9 in cash (net of cash acquired), bringing the Company’s percentage interest owned to 85.6%. Concurrent with this acquisition, the terms of the joint venture’s partnership agreement were amended. The amended joint venture’s partnership agreement enabled the holders of the noncontrolling interest to put the remaining partnership units to the Company in defined future periods, at an initial amount equal to the consideration paid by the Company in 2008, and subject to adjustment based on market value formulas contained in the agreement. The initial difference of $123.0 between the value of the put and the underlying noncontrolling interest was recorded as additional noncontrolling interest liability and as a reduction to additional paid-in capital in the consolidated financial statements. In December 2009, the Company received notification from the holders of the noncontrolling interest in the Ontario joint venture that they intended to put their remaining partnership units to the Company in accordance with the terms of the joint venture’s partnership agreement. These units were acquired on February 8, 2010 for $137.5. On February 17, 2010, the Company completed a transaction to sell the units acquired from the previous noncontrolling interest holder to a new Canadian partner for the same price. As a result of this transaction, the Company recorded a component of noncontrolling interest in other liabilities and a component in mezzanine equity. Upon the completion of these two transactions, the Company’s financial ownership percentage in the joint venture partnership remained unchanged at 85.6%. Concurrent with the sale to the new partner, the partnership agreement for the Ontario joint venture was amended and restated with substantially the same terms as the previous agreement. The combined contractual value of these puts, in excess of the current noncontrolling interest of $25.2, totals $143.5 at December 31, 2010. At December 31, 2010, $148.1 has been classified as a current liability in the Company’s consolidated balance sheet as the noncontrolling interest that acquired these units has the ability to put its units in the partnership to the Company on December 31, 2011. Net sales of the Ontario joint venture were $280.0 (CN$288.5), $247.5 (CN$281.3) and $249.0 (CN$264.4) for the twelve months ended December 31, 2010, 2009 and 2008, respectively.

RESTRUCTURING AND OTHER SPECIAL CHARGES	12 Months Ended
RESTRUCTURING AND OTHER SPECIAL CHARGES	Dec. 31, 2010
Notes To Financial Statements [Abstract]
RESTRUCTURING AND OTHER SPECIAL CHARGES	3. RESTRUCTURING AND OTHER SPECIAL CHARGES During 2010, the Company recorded net restructuring charges of $5.8 primarily related to work force reductions and the closing of redundant and underutilized facilities. The majority of these costs related to severance and other employee costs and contractual obligations associated with leased facilities and other facility related costs. Of this amount, $8.0 related to severance and other employee costs in connection with certain work force reductions and $3.1 related to contractual obligations associated with leased facilities and other facility related costs. The Company also reduced its prior restructuring accruals by $5.3, comprised of $4.7 of previously recorded facility costs and $0.6 of employee severance benefits as a result of changes in cost estimates on the restructuring initiatives. In addition, the Company recorded a special charge of $6.2 related to the write-off of development costs incurred on systems abandoned during the year. During 2009, the Company recorded net restructuring charges of $13.5 primarily related to the closing of redundant and underutilized facilities. The majority of these costs related to severance and other employee costs and contractual obligations associated with leased facilities and other facility related costs. Of this amount, $10.5 related to severance and other employee costs for employees primarily in the affected facilities, and $12.5 related to contractual obligations associated with leased facilities and other facility related costs. The Company also reduced its prior restructuring accruals by $9.5, comprised of $7.3 of previously recorded facility costs and $2.2 of employee severance benefits as a result of incurring less cost than planned on those restructuring initiatives primarily resulting from favorable settlements on lease buyouts and severance payments that were not required to achieve the planned reduction in work force. During 2008, the Company recorded net restructuring charges of $32.4 primarily related to work force reductions and the closing of redundant and underutilized facilities. Of this amount, $20.9 related to severance and other employee costs in connection with the general work force reductions and $13.4 related to contractual obligations associated with leased facilities and equipment. The Company also recorded a credit of $1.9, comprised of $1.2 of previously recorded facility costs and $0.7 of employee severance benefits relating to changes in cost estimates accrued in prior periods. During the third quarter of 2008, the Company also recorded a special charge of $5.5 related to estimated uncollectible amounts primarily owed by patients in the areas of the Gulf Coast severely impacted by hurricanes similar to losses incurred during the 2005 hurricane season.

RESTRUCTURING RESERVES

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

RESTRUCTURING RESERVES

4. RESTRUCTURING RESERVES

The following represents the Company’s restructuring activities for the period indicated:

	Severance			Lease
	and Other			and Other
	Employee			Facility
	Costs			Costs			Total
Balance as of December 31, 2009	$	6.6		$	19.0		$	25.6
Restructuring charges		8.0			3.1			11.1
Reduction of prior restructuring accruals		(0.6	)		(4.7	)		(5.3	)
Cash payments and other adjustments		(9.1	)		(4.5	)		(13.6	)
Balance as of December 31, 2010	$	4.9		$	12.9		$	17.8

Current							$	11.4
Non-current								6.4
							$	17.8

JOINT VENTURE PARTNERSHIPS AND EQUITY METHOD INVESTMENTS

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Joint venture partnerships and equity method investments

5. JOINT VENTURE PARTNERSHIPS AND EQUITY METHOD INVESTMENTS

At December 31, 2010 the Company had investments in the following unconsolidated joint venture partnerships and equity method investments:

	Net		Percentage
Locations	Investment		Interest Owned
Joint Venture Partnerships:
Milwaukee, Wisconsin	$	9.2		50.00	%
Alberta, Canada		60.9		43.37	%
Cincinnati, Ohio		0.0		50.00	%
Equity Method Investments:
Canada, China and Western Europe		5.4		17.50	%
Charlotte, North Carolina		3.0		50.00	%

The joint venture agreements that govern the conduct of business of these partnerships mandates unanimous agreement between partners on all major business decisions as well as providing other participating rights to each partner. The equity method investments represent the Company’s purchase of shares in clinical diagnostic companies. The investments are accounted for under the equity method of accounting as the Company does not have control of these investments. The Company has no material obligations or guarantees to, or in support of, these unconsolidated investments and their operations.

Condensed unconsolidated financial information for joint venture partnerships and equity method investments is shown in the following table.

As of December 31:	2010		2009
Current assets	$	61.9	$	35.3
Other assets		48.4		41.4
Total assets		110.3		76.7
Current liabilities		55.6		28.0
Other liabilities		17.9		2.3
Total liabilities		73.5		30.3
Partners' equity		36.8		46.4
Total liabilities and partners’ equity	$	110.3	$	76.7

For the period January 1 - December 31:	2010		2009		2008
Net sales	$	255.5	$	212.4	$	182.0
Gross profit		73.9		69.6		69.0
Net earnings		20.0		33.3		34.3

The Company’s recorded investment in the Alberta joint venture partnership at December 31, 2010 includes $48.9 of value assigned to the partnership’s Canadian licenses (with an indefinite life and deductible for tax) to conduct diagnostic testing services in the province.

- Definition

Equity investment disclosure, or group of investments for which combined disclosure is appropriate, including: (a) the name of each investee and percentage of ownership of common stock, (b) accounting policies for investments in common stock, (c) difference between the amount at which the investment is carried and the amount of underlying equity in net assets and the accounting treatment of the difference, (d) the total fair value of each identified investment for which a market value is available, (e) summarized information as to assets, liabilities, and results of operations of the investees (for investments in unconsolidated subsidiaries, common stock of joint ventures, or other investments using the equity method), and (f) material effects of possible conversions, exercises, or contingent issuances of the investee. Other disclosures include (a) the names of any investee in which the investor owns 20 percent or more of the voting stock and investment is not accounted for using the equity method, and the reasons why not, and (b) the names of any investee in which the investor owns less than 20% of the voting stock and the investment is accounted for using the equity method, and the reasons why it is.

+ References+ Details

ACCOUNTS RECEIVABLE, NET

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

ACCOUNTS RECEIVABLE, NET

6. ACCOUNTS RECEIVABLE, NET

	December 31,			December 31,
	2010			2009
Gross accounts receivable	$	804.8		$	747.3
Less allowance for doubtful accounts		(149.2	)		(173.1	)
	$	655.6		$	574.2

The provision for doubtful accounts was $241.5, $248.9 and $232.8 in 2010, 2009 and 2008 respectively. In addition, in the second quarter of 2008 the Company recorded a $45.0 increase in its provision for doubtful accounts. The Company’s estimate of the allowance for doubtful accounts was increased due to the impact of the economy, higher patient deductibles and copayments, and acquisitions on the collectibility of accounts receivable balances.

During the third quarter of 2008, the Company also recorded a special charge of $5.5 related to estimated uncollectible amounts primarily owed by patients in the areas of the Gulf Coast severely impacted by hurricanes similar to losses incurred during the 2005 hurricane season.

PROPERTY, PLANT AND EQUIPMENT, NET

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Property, plant and equipment, net

7. PROPERTY, PLANT AND EQUIPMENT, NET

	December 31,			December 31,
	2010			2009
Land	$	25.8		$	23.4
Buildings and building improvements		125.4			116.7
Machinery and equipment		615.7			584.8
Software		299.2			289.6
Leasehold improvements		171.6			147.0
Furniture and fixtures		51.2			48.4
Construction in progress		95.6			49.8
Equipment under capital leases		3.5			3.5
		1,388.0			1,263.2
Less accumulated depreciation and amortization of capital lease assets		(801.1	)		(762.4	)
	$	586.9		$	500.8

Depreciation expense and amortization of capital lease assets was $129.1, $130.7 and $120.1 for 2010, 2009 and 2008, respectively, including software depreciation of $32.0, $34.8, and $33.7 for 2010, 2009 and 2008, respectively.

GOODWILL AND INTANGIBLE ASSETS

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

GOODWILL AND INTANGIBLE ASSETS

8. GOODWILL AND INTANGIBLE ASSETS

The changes in the carrying amount of goodwill (net of accumulated amortization) for the years ended December 31, 2010 and 2009 are as follows:

	2010			2009
Balance as of January 1	$	1,897.1		$	1,772.2
Goodwill acquired during the year		704.4			124.1
Adjustments to goodwill		(0.2	)		0.8
Goodwill, net	$	2,601.3		$	1,897.1

The components of identifiable intangible assets are as follows:

	December 31, 2010					December 31, 2009
	Gross					Gross
	Carrying		Accumulated			Carrying		Accumulated
	Amount		Amortization			Amount		Amortization

Customer relationships	$	1,146.0	$	(370.0	)	$	839.8	$	(337.1	)
Patents, licenses and technology		144.7		(75.7	)		119.2		(62.4	)
Non-compete agreements		26.6		(9.4	)		39.4		(30.7	)
Trade name		123.3		(50.3	)		117.7		(41.8	)
Canadian licenses		738.9		--			698.1		--
	$	2,179.5	$	(505.4	)	$	1,814.2	$	(472.0	)

A summary of amortizable intangible assets acquired during 2010, and their respective weighted average amortization periods are as follows:

			Weighted
			Average
			Amortization
	Amount		Period

Customer relationships	$	319.9		19.2
Patents, licenses and technology		25.5		0.6
Non-compete agreements		12.8		0.2
Trade name		5.6		--
	$	363.8		20.0

Amortization of intangible assets was $72.7, $62.6 and $57.9 in 2010, 2009 and 2008, respectively. Amortization expense of intangible assets is estimated to be $85.1 in fiscal 2011, $80.4 in fiscal 2012, $74.7 in fiscal 2013, $71.9 in fiscal 2014, $68.3 in fiscal 2015, and $554.8 thereafter.

The Company paid $0.4, $0.0 and $0.8 in 2010, 2009 and 2008 for certain exclusive and non-exclusive licensing rights to diagnostic testing technology. These amounts are being amortized over the life of the licensing agreements.

As of December 31, 2010, the Ontario operation has $738.9 of value assigned to the partnership’s indefinite lived Canadian licenses to conduct diagnostic testing services in the province.

- Definition

Discloses the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain or loss on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss. This element may be used as a single block of text to include the entire intangible asset disclosure including data and tables.

+ References+ Details

ACCRUED EXPENSES AND OTHER

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

ACCRUED EXPENSES AND OTHER

9. ACCRUED EXPENSES AND OTHER

	December 31,		December 31,
	2010		2009
Employee compensation and benefits	$	188.0	$	143.4
Self-insurance reserves		70.8		56.2
Accrued taxes payable		13.8		19.0
Royalty and license fees payable		12.6		6.9
Accrued repurchases of common stock		--		0.5
Restructuring reserves		11.4		15.2
Acquisition related reserves		18.4		5.6
Interest payable		13.0		8.6
Other		24.9		20.3
	$	352.9	$	275.7

OTHER LIABILITIES

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Other liabilities

10. OTHER LIABILITIES

	December 31,		December 31,
	2010		2009
Post-retirement benefit obligation	$	42.0	$	39.6
Defined benefit plan obligation		52.8		41.4
Restructuring reserves		6.4		10.4
Self-insurance reserves		12.1		12.1
Interest rate swap liability		2.4		10.6
Acquisition related reserves		0.6		1.1
Deferred revenue		7.2		22.5
Other		27.9		20.7
	$	151.4	$	158.4

DEBT

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Debt

11. DEBT

Short-term borrowings and current portion of long-term debt at December 31, 2010 and 2009 consisted of the following:

	December 31,		December 31,
	2010		2009
Zero-coupon convertible subordinated notes	$	286.7	$	292.2
Term loan, current		75.0		50.0
Revolving credit facility		--		75.0
Total short-term borrowings and current portion of long-term debt	$	361.7	$	417.2

Long-term debt at December 31, 2010 and 2009 consisted of the following:

	December 31,		December 31,
	2010		2009
Senior notes due 2013	$	350.9	$	351.3
Senior notes due 2015		250.0		250.0
Senior notes due 2016		325.0		--
Senior notes due 2020		600.0		--
Term loan, non-current		300.0		375.0
Other long-term debt		0.8		0.9
Total long-term debt	$	1,826.7	$	977.2

Credit Facilities

On October 26, 2007, the Company entered into senior unsecured credit facilities with Credit Suisse, acting as Administrative Agent, and a group of financial institutions totaling $1,000.0. The credit facilities consist of a five-year Revolving Facility in the principal amount of $500.0 and a five-year, $500.0 Term Loan Facility. The balances outstanding on the Company’s Term Loan Facility at December 31, 2010 and 2009 were $375.0 and $425.0, respectively. The balances outstanding on the Company’s Revolving

Facility at December 31, 2010 and 2009 were $0.0 and $75.0, respectively. The senior unsecured credit facilities bear interest at varying rates based upon LIBOR plus a percentage based on the Company’s credit rating with Standard & Poor's Ratings Services. The remaining quarterly principal repayments of the Term Loan Facility are $18.8 from March 31, 2011 to September 30, 2012 with $243.8 due on the maturity date of October 26, 2012. At December 31, 2010, future principal repayments under the Term Loan facility are as follows: 2011 - $75.0 and 2012 - $300.0.

The senior credit facilities are available for general corporate purposes, including working capital, capital expenditures, acquisitions, funding of share repurchases and other payments. The agreement contains certain debt covenants which require that the Company maintain a leverage ratio of no more than 2.5 to 1.0 and an interest coverage ratio of at least 5.0 to 1.0. Both ratios are calculated in relation to EBITDA (Earnings Before Interest, Taxes, Depreciation, and Amortization). The credit agreement allows payment of dividends provided that the Company is not in default (as defined in the agreement) and its leverage ratio is less than 2.0 to 1.0. The Company is in compliance with all covenants at December 31, 2010.

On March 31, 2008, the Company entered into a three-year interest rate swap agreement to hedge variable interest rate risk on the Company’s variable interest rate term loan. On a quarterly basis under the swap, the Company pays a fixed rate of interest (2.92%) and receives a variable rate of interest based on the three-month LIBOR rate on an amortizing notional amount of indebtedness equivalent to the term loan balance outstanding. The swap has been designated as a cash flow hedge. Accordingly, the Company recognizes the fair value of the swap in the consolidated balance sheets and any changes in the fair value are recorded as adjustments to accumulated other comprehensive income (loss), net of tax. The fair value of the interest rate swap agreement is the estimated amount that the Company would pay or receive to terminate the swap agreement at the reporting date. The fair value of the swap was a liability of $2.4 and $10.6 at December 31, 2010 and 2009, respectively, and is included in other liabilities in the consolidated balance sheets.

As of December 31, 2010, the effective interest rates on the Term Loan Facility and Revolving Facility were 3.67% and 0.61%, respectively.

Zero-Coupon Convertible Subordinated Notes

The Company had $354.6 and $368.8 aggregate principal amount at maturity of zero-coupon convertible subordinated notes (the “notes”) due 2021 outstanding at December 31, 2010 and 2009, respectively. The notes, which are subordinate to the Company’s bank debt, were sold at an issue price of $671.65 per $1,000 principal amount at maturity (representing a yield to maturity of 2.0% per year). Each one thousand dollar principal amount at maturity of the notes is convertible into 13.4108 shares of the Company’s common stock, subject to adjustment in certain circumstances, if one of the following conditions occurs:

1)	If the sales price of the Company’s common stock for at least 20 trading days in a period of 30 consecutive trading days ending on the last trading day of the preceding quarter reaches specified thresholds (beginning at 120% and declining 0.1282% per quarter until it reaches approximately 110% for the quarter beginning July 1, 2021 of the accreted conversion price per share of common stock on the last day of the preceding quarter). The accreted conversion price per share will equal the issue price of a note plus the accrued original issue discount and any accrued contingent additional principal, divided by the number of shares of common stock issuable upon conversion of a note on that day. The conversion trigger price for the fourth quarter of 2010 was $69.27.
2)	If the credit rating assigned to the notes by Standard & Poor’s Ratings Services is at or below BB-.
3)	If the notes are called for redemption.
4)	If specified corporate transactions have occurred (such as if the Company is party to a consolidation, merger or binding share exchange or a transfer of all or substantially all of its assets).

Holders of the notes may require the Company to purchase in cash all or a portion of their notes on September 11, 2011 at $819.54 per note, plus any accrued contingent additional principal and any accrued contingent interest thereon.

The Company may redeem for cash all or a portion of the notes at any time on or after September 11, 2006 at specified redemption prices per one thousand dollar principal amount at maturity of the notes.

The Company has registered the notes and the shares of common stock issuable upon conversion of the notes with the Securities and Exchange Commission.

During the second quarter of 2009, the Company redeemed approximately $369.5 principal amount at maturity of its zero-coupon subordinated notes, equaling approximately 50% of the principal amount at maturity outstanding of the zero-coupon subordinated notes. The total cash used for these redemptions was $289.4. As a result of certain holders of the zero-coupon subordinated notes electing to convert their notes, the Company also issued 0.4 additional shares of common stock and reversed approximately $11.3 of deferred tax liability to reflect the tax benefit realized upon issuance of these shares.

On September 13, 2010, the Company announced that for the period of September 12, 2010 to March 11, 2011, the zero-coupon subordinated notes will accrue contingent cash interest at a rate of no less than 0.125% of the average market price of a zero-coupon subordinated note for the five trading days ended September 8, 2010, in addition to the continued accrual of the original issue discount.

On January 3, 2011, the Company announced that its zero-coupon subordinated notes may be converted into cash and common stock at the conversion rate of 13.4108 per $1,000 principal amount at maturity of the notes, subject to the terms of the zero-coupon subordinated notes and the Indenture, dated as of October 24, 2006 between the Company and The Bank of New York Mellon, as trustee and conversion agent. In order to exercise the option to convert all or a portion of the zero-coupon subordinated notes, holders are required to validly surrender their zero-coupon subordinated notes at any time during the calendar quarter beginning January 1, 2011, through the close of business on the last business day of the calendar quarter, which is 5:00 p.m., New York City time, on Thursday, March 31, 2011.

Senior Notes

On October 28, 2010, in conjunction with the acquisition of Genzyme Genetics, the Company entered into a $925.0 Bridge Term Loan Credit Agreement, among the Company, the lenders named therein and Citibank, N.A., as administrative agent (the “Bridge Facility”). The Company replaced and terminated the Bridge Facility in November 2010 by making an offering in the debt capital markets. On November 19, 2010, the Company sold $925.0 in debt securities, consisting of $325.0 aggregate principal amount of 3.125% Senior Notes due May 15, 2016 and $600.0 aggregate principal amount of 4.625% Senior Notes due November 15, 2020. Beginning on May 15, 2011, interest on the Senior Notes due 2016 and 2020 is payable semi-annually on May 15 and November 15. On December 1, 2010, the acquisition of Genzyme Genetics was funded by the net proceeds from the issuance of these Notes ($915.4) and with cash on hand.

The Senior Notes due January 31, 2013 bear interest at the rate of 5 1/2% per annum from February 1, 2003, payable semi-annually on February 1 and August 1. The Senior Notes due 2015 bear interest at the rate of 5 5/8% per annum from December 14, 2005, payable semi-annually on June 15 and December 15.

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Preferred Stock and Common Shareholders' Equity

12. PREFERRED STOCK AND COMMON SHAREHOLDERS’ EQUITY

The Company is authorized to issue up to 265.0 shares of common stock, par value $0.10 per share. The Company’s treasury shares are recorded at aggregate cost. Common shares issued and outstanding are summarized in the following table:

	2010			2009

Issued		124.5			127.4
In treasury		(22.1	)		(22.1	)
Outstanding		102.4			105.3

The Company is authorized to issue up to 30.0 shares of preferred stock, par value $0.10 per share. There were no preferred shares outstanding as of December 31, 2010.

The changes in common shares issued and held in treasury are summarized below:

Common shares issued
	2010			2009			2008
Common stock issued at January 1		127.4			130.3			132.7
Common stock issued under employee stock plans		1.6			0.6			2.2
Common stock issued upon conversion of zero-coupon
subordinated notes		--			0.4			--
Retirement of common stock		(4.5	)		(3.9	)		(4.6	)
Common stock issued at December 31		124.5			127.4			130.3

Common shares held in treasury
	2010		2009		2008
Common shares held in treasury at January 1		22.1		22.1		21.7
Surrender of restricted stock and performance share awards		--		--		0.4
Common shares held in treasury at December 31		22.1		22.1		22.1

Share Repurchase Program

During fiscal 2010, the Company purchased 4.5 shares of its common stock at a total cost of $337.5. As of December 31, 2010, the Company had outstanding authorization from the Board of Directors to purchase approximately $234.3 of Company common stock. During January 2011, the Company completed its repurchase authorization, representing approximately 2.6 shares of its common stock. On February 10, 2011, the Company announced the Board of Directors authorized the purchase of $500.0 of additional shares of the Company’s common stock.

Stockholder Rights Plan

The Company adopted a stockholder rights plan effective as of December 13, 2001 that provides that each common stockholder of record on December 21, 2001 received a dividend of one right for each share of common stock held. Each right entitles the holder to purchase from the Company one-hundredth of a share of a new series of participating preferred stock at an initial purchase price of four hundred dollars. These rights will become exercisable and will detach from the Company’s common stock if any person becomes the beneficial owner of 15% or more of the Company’s common stock. In that event, each right will entitle the holder, other than the acquiring person, to purchase, for the initial purchase price, shares of the Company’s common stock having a value of twice the initial purchase price. The rights will expire on December 13, 2011, unless earlier exchanged or redeemed.

Accumulated Other Comprehensive Earnings

The components of accumulated other comprehensive earnings are as follows:

	Foreign			Net			Interest			Accumulated
	Currency			Benefit			Rate			Other
	Translation			Plan			Swap			Comprehensive
	Adjustments			Adjustments			Adjustments			Earnings
Balance at December 31, 2007	$	148.1		$	(28.1	)	$	--		$	120.0
Current year adjustments		(129.6	)		(81.0	)		(13.5	)		(224.1	)
Tax effect of adjustments		50.1			32.0			5.3			87.4
Balance at December 31, 2008		68.6			(77.1	)		(8.2	)		(16.7	)
Current year adjustments		93.3			31.5			2.9			127.7
Tax effect of adjustments		(36.1	)		(12.2	)		(1.2	)		(49.5	)
Balance at December 31, 2009		125.8			(57.8	)		(6.5	)		61.5
Current year adjustments		41.3			(8.3	)		8.2			41.2
Tax effect of adjustments		(14.3	)		3.2			(3.1	)		(14.2	)
Balance at December 31, 2010	$	152.8		$	(62.9	)	$	(1.4	)	$	88.5

- Definition

Disclosures related to accounts comprising shareholders' equity, including other comprehensive income. Includes: (1) balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings; (2) accumulated balance for each classification of other comprehensive income and total amount of comprehensive income; (3) amount and nature of changes in separate accounts, including the number of shares authorized and outstanding, number of shares issued upon exercise and conversion, and for other comprehensive income, the adjustments for reclassifications to net income; (4) rights and privileges of each class of stock authorized; (5) basis of treasury stock, if other than cost, and amounts paid and accounting treatment for treasury stock purchased significantly in excess of market; (6) dividends paid or payable per share and in the aggregate for each class of stock for each period presented; (7) dividend restrictions and accumulated preferred dividends in arrears (in aggregate and per share amount); (8) retained earnings appropriations or restrictions, such as dividend restrictions; (9) impact of change in accounting principle, initial adoption of new accounting principle and correction of an error in previously issued financial statements; (10) shares held in trust for Employee Stock Ownership Plan (ESOP); (11) deferred compensation related to issuance of capital stock; (12) note received for issuance of stock; (13) unamortized discount on shares; (14) description, terms and number of warrants or rights outstanding; (15) shares under subscription and subscription receivables; effective date of new retained earnings after quasi-reorganization and deficit eliminated by quasi-reorganization and, for a period of at least ten years after the effective date, the point in time from which the new retained dates; and (16) retroactive effective of subsequent change in capital structure.

+ References+ Details

INCOME TAXES

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Income Taxes

13. INCOME TAXES

The sources of income before taxes, classified between domestic and foreign entities are as follows:

Pre-tax income	2010		2009		2008

Domestic	$	876.1	$	848.0	$	747.8
Foreign		39.5		36.6		37.9
Total pre-tax income	$	915.6	$	884.6	$	785.7

The provisions for income taxes in the accompanying consolidated statements of operations consist of the following:

	Years Ended December 31,
	2010			2009			2008
Current:
Federal	$	269.9		$	266.2		$	188.1
State		50.4			41.0			39.8
Foreign		10.8			12.2			10.4
	$	331.1		$	319.4		$	238.3
Deferred:
Federal	$	12.2		$	25.3		$	54.0
State		(0.5	)		(15.5	)		12.8
Foreign		1.2			(0.2	)		2.8
		12.9			9.6			69.6
	$	344.0		$	329.0		$	307.9

The tax benefit associated with option exercises from stock plans reduced taxes currently payable by approximately $7.8, $1.1 and $20.9 in 2010, 2009 and 2008, respectively. Such benefits are recorded as additional paid-in-capital.

The effective tax rates on earnings before income taxes are reconciled to statutory federal income tax rates as follows:

	Years Ended December 31,
	2010			2009			2008
Statutory federal rate		35.0	%		35.0	%		35.0	%
State and local income taxes, net of federal income tax effect		3.5			1.9			4.3
Other		(0.9	)		0.3			(0.1	)
Effective rate		37.6	%		37.2	%		39.2	%

The effective tax rate for 2010 was favorably impacted by a benefit relating to the net decrease in unrecognized income tax benefits. In 2009, the Company recorded favorable adjustments of $21.5 to its tax provision relating to the resolution of certain state tax issues under audit, as well as the realization of foreign tax credits.

The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are as follows:

	December 31,			December 31,
	2010			2009
Deferred tax assets:
Accounts receivable	$	2.6		$	12.1
Employee compensation and benefits		96.3			72.0
Self insurance reserves		27.1			20.2
Postretirement benefit obligation		16.3			15.4
Acquisition and restructuring reserves		10.2			11.6
Tax loss carryforwards		50.1			45.9
		202.6			177.2
Less: valuation allowance		(11.4	)		(3.9	)
Net deferred tax assets	$	191.2		$	173.3

Deferred tax liabilities:
Deferred earnings		(18.0	)		(23.1	)
Intangible assets		(343.8	)		(336.7	)
Property, plant and equipment		(63.3	)		(58.5	)
Zero-coupon subordinated notes		(145.2	)		(136.5	)
Currency translation adjustment		(94.3	)		(78.0	)
Other		(5.1	)		(2.2	)
Total gross deferred tax liabilities		(669.7	)		(635.0	)
Net deferred tax liabilities	$	(478.5	)	$	(461.7	)

The Company has state tax loss carryovers of approximately $0.3, which expire in 2010 through 2024. During 2010, $0.2 of state net operating losses expired and such losses had a full valuation allowance. The Company has foreign tax loss carryovers of $7.7 having an indefinite carryover. The foreign tax loss carryovers have a full valuation allowance provided. In addition, the Company has federal tax loss carryovers of approximately $42.1 expiring periodically through 2028. The utilization of these tax loss carryovers is limited due to change of ownership rules. However, at this time the Company expects to fully utilize substantially all federal tax loss carryovers.

The gross unrecognized income tax benefits were $53.6 and $59.0 at December 31, 2010 and 2009, respectively. It is anticipated that the amount of the unrecognized income tax benefits will change within the next twelve months; however, these changes are not expected to have a significant impact on the results of operations, cash flows or the financial position of the Company.

The Company recognizes interest and penalties related to unrecognized income tax benefits in income tax expense. Accrued interest and penalties related to uncertain tax positions totaled $12.2 and $14.7 as of December 31, 2010 and 2009, respectively. During the years ended December 31, 2010, 2009 and 2008, the Company recognized $4.5, $5.4 and $4.5, respectively, in interest and penalties expense, which was offset by a benefit of $5.4, $4.9 and $1.4, respectively.

The following table shows a reconciliation of the unrecognized income tax benefits from uncertain tax positions for the years ended December 31, 2010, 2009 and 2008:

	2010			2009			2008
Balance as of January 1	$	59.0		$	72.5		$	55.7
Increase in reserve for tax positions taken in the current year		9.1			10.9			13.4
Increase (decrease) in reserve for tax positions taken in a
prior period		(0.6	)		(4.2	)		5.2
Decrease in reserve as a result of settlements reached with
tax authorities		(1.3	)		(15.7	)		(0.6	)
Decrease in reserve as a result of lapses in the statute of
limitations		(12.6	)		(4.5	)		(1.2	)
Balance as of December 31	$	53.6		$	59.0		$	72.5

As of December 31, 2010 and 2009, $54.6 and $60.3, respectively, is the approximate amount of unrecognized income tax benefits that, if recognized, would favorably affect the effective income tax rate in any future periods.

The Company has substantially concluded all U.S. federal income tax matters for years through 2006. Substantially all material state and local, and foreign income tax matters have been concluded through 2005 and 2001, respectively.

The Company has various state income tax examinations ongoing throughout the year. Management believes adequate provisions have been recorded related to all open tax years.

The Company provided for taxes on undistributed earnings of foreign subsidiaries.

STOCK COMPENSATION PLANS

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Stock Compensation Plans

14. STOCK COMPENSATION PLANS

Stock Incentive Plans

There are currently 23.8 shares authorized for issuance under the 2008 Stock Incentive Plan and the 2000 Stock Incentive Plan. Each of these plans was approved by shareholders. At December 31, 2010, there were 4.0 additional shares available for grant under the Company’s stock option plans.

Stock Options

The following table summarizes grants of non-qualified options made by the Company to officers, key employees, and non-employee directors under all plans. Stock options are generally granted at an exercise price equal to or greater than the fair market price per share on the date of grant. Also, for each grant, options vest ratably over a period of three years on the anniversaries of the grant date, subject to their earlier expiration or termination.

Changes in options outstanding under the plans for the periods indicated were as follows:

						Weighted-
				Weighted-		Average
				Average		Remaining		Aggregate
	Number of			Exercise Price		Contractual		Intrinsic
	Options			per Option		Term		Value
Outstanding at December 31, 2009		6.3		$	64.52
Granted		1.8			70.47
Exercised		(1.3	)		55.12
Cancelled		(0.2	)		71.51
Outstanding at December 31, 2010		6.6		$	67.84		7.4	$	132.3
Vested and expected to vest
at December 31, 2010		6.5		$	67.84		7.4	$	130.2
Exercisable at December 31, 2010		3.2		$	68.09		6.2	$	62.9

The aggregate intrinsic value in the table above represents the total pre-tax intrinsic value (the difference between the Company’s closing stock price on the last trading day of 2010 and the exercise price, multiplied by the number of in-the-money options) that would have been received by the option holders had all option holders exercised their options on December 31, 2010. The amount of intrinsic value will change based on the fair market value of the Company’s stock.

Cash received by the Company from option exercises, the actual tax benefit realized for the tax deductions and the aggregate intrinsic value of options exercised from option exercises under all share-based payment arrangements during the years ended December 31, 2010, 2009, and 2008 were as follows:

	2010		2009		2008

Cash received by the Company	$	73.7	$	14.3	$	53.6
Tax benefits realized	$	13.2	$	2.7	$	14.3
Aggregate intrinsic value	$	33.4	$	7.0	$	35.5

The following table summarizes information concerning currently outstanding and exercisable options.

Options Outstanding								Options Exercisable
				Weighted Average						Weighted
				Remaining		Average				Average
Range of		Number		Contractual		Exercise		Number		Exercise
Exercise Prices		Outstanding		Life		Price		Exercisable		Price

	$ 6.80 - 59.37		0.9		4.3		$51.41		0.9		$51.41
	$59.38 - 67.60		1.7		8.1		$60.33		0.4		$60.42
	$67.61 - 75.63		3.0		8.3		$72.67		0.9		$75.63
	$75.64 - 80.37		1.0		6.3		$80.17		1.0		$80.31
			6.6		7.4		$67.84		3.2		$68.09

The following table shows the weighted average grant-date fair values of options and the weighted average assumptions that the Company used to develop the fair value estimates:

	2010			2009			2008

Fair value per option	$	14.12		$	10.85		$	13.25
Valuation assumptions
Weighted average expected life (in years)		3.1			3.0			3.2
Risk free interest rate		1.5	%		1.1	%		2.7	%
Expected volatility		0.3			0.2			0.2
Expected dividend yield		0.0	%		0.0	%		0.0	%

The Black Scholes model incorporates assumptions to value stock-based awards. The risk-free interest rate for periods within the contractual life of the option is based on a zero-coupon U.S. government instrument over the contractual term of the equity instrument. Expected volatility of the Company’s stock is based on historical volatility of the Company’s stock. The Company uses historical data to calculate the expected life of the option. Groups of employees and non-employee directors that have similar exercise behavior with regard to option exercise timing and forfeiture rates are considered separately for valuation purposes. For 2010, 2009 and 2008, expense related to the Company’s stock option plan totaled $20.7, $18.7 and $17.3, respectively. The 2008 expense amount includes $0.8 related to the acceleration of the recognition of stock compensation as a result of the retirement of an Executive Vice President.

Restricted Stock and Performance Shares

The Company grants restricted stock and performance shares (“nonvested shares”) to officers, key employees, and non-employee directors under all plans. Restricted stock becomes vested annually in equal one third increments beginning on the first anniversary of the grant. The performance share awards represented a three year award opportunity for the period 2005-2007 and became vested in 2008. A performance share grant in 2008 represents a three year award opportunity for the period 2008-2010 and becomes vested in the first quarter of 2011. A performance share grant in 2009 represents a three year award opportunity for the period of 2009-2011 and becomes vested in the first quarter of 2012. A performance share grant in 2010 represents a three year award opportunity for the period of 2010-2012 and becomes vested in the first quarter of 2013. Performance share awards are subject to certain earnings per share and revenue targets, the achievement of which may increase or decrease the number of shares which the grantee receives upon vesting. The unearned restricted stock and performance share compensation is being amortized to expense over the applicable vesting periods. For 2010, 2009 and 2008, total restricted stock and performance share compensation expense was $16.1, $13.6 and $14.0, respectively. The 2008 expense amount includes $1.2 related to the acceleration of the recognition of stock compensation as a result of the retirement of an Executive Vice President.

Prior to May 2008, the fair value of restricted stock and performance share awards was determined based on the closing price of the Company’s common stock on the day immediately preceding the grant date. For restricted stock and performance share awards granted after May 2008, the fair value of the awards is determined based on the closing price of the Company’s common stock on the day of the grant.

The following table shows a summary of nonvested shares for the year ended December 31, 2010:

				Weighted-
				Average
	Number of			Grant Date
	Shares			Fair Value
Nonvested at January 1, 2010		0.5		$	69.43
Granted		0.2			70.60
Vested		(0.1	)		72.52
Nonvested at December 31, 2010		0.6			68.26

As of December 31, 2010, there was $20.8 of total unrecognized compensation cost related to nonvested restricted stock and performance share-based compensation arrangements granted under the stock incentive plans. That cost is expected to be recognized over a weighted average period of 1.8 years.

Employee Stock Purchase Plan

The Company has an employee stock purchase plan, begun in 1997 and amended in 1999, 2004 and 2008, with 4.5 shares of common stock authorized for issuance. The plan permits substantially all employees to purchase a limited number of shares of Company stock at 85% of market value. The Company issues shares to participating employees semi-annually in January and July of each year. Approximately 0.2 shares were purchased by eligible employees in 2010, 2009 and 2008, respectively. For 2010, 2009 and 2008, expense related to the Company’s employee stock purchase plan was $2.6, $2.7 and $2.9, respectively.

The Company uses the Black-Scholes model to calculate the fair value of the employee’s purchase right. The fair value of the employee’s purchase right and the assumptions used in its calculation are as follows:

	2010			2009			2008

Fair value of the employee’s purchase right	$	15.39		$	14.28		$	16.10
Valuation assumptions
Risk free interest rate		0.2	%		0.2	%		1.2	%
Expected volatility		0.2			0.2			0.3
Expected dividend yield		0.0	%		0.0	%		0.0	%

COMMITMENTS AND CONTINGENT LIABILITIES

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

COMMITMENTS AND CONTINGENT LIABILITIES

15. COMMITMENTS AND CONTINGENT LIABILITIES

The Company was a party in a patent case originally filed by Competitive Technologies, Inc. and Metabolite Laboratories, Inc. in the United States District Court for the District of Colorado. After a jury trial, the district court entered judgment against the Company for patent infringement, with total damages and attorney’s fees payable by the Company of approximately $7.8. The underlying judgment has been paid. The Company vigorously contested the judgment and appealed the case ultimately to the United States Supreme Court. On June 22, 2006, the Supreme Court dismissed the Company’s appeal and the case was remanded to the District Court for further proceedings including resolution of a related declaratory judgment action initiated by the Company addressing the plaintiffs’ claims for post trial damages. On August 15, 2008, the District Court entered judgment in favor of the Company on all of the plaintiffs’ remaining claims. Metabolite Laboratories, Inc. filed an appeal to the Federal Circuit. The Federal Circuit transferred the appeal to the Tenth Circuit Court of Appeals and oral argument was heard on November 17, 2010. On February 2, 2011, the Tenth Circuit Court of Appeals affirmed the District Court judgment in favor of the Company.

A subsidiary of the Company, DIANON Systems, Inc. (“DIANON”), is the appellant in a wrongful termination lawsuit originally filed by G. Berry Schumann in Superior Court in the State of Connecticut. After a jury trial, the state court entered judgment against DIANON, with total damages, attorney’s fees, and pre-judgment interest payable by DIANON, of approximately $10.0. DIANON filed a notice of appeal in December 2009, and the case has been transferred to the Connecticut Supreme Court. DIANON has disputed liability and intends to contest the case vigorously on appeal.

As previously reported on May 22, 2006, the Company received a subpoena from the California Attorney General seeking documents related to billing to the state’s Medicaid program. During the third quarter of 2008, the Company received a request from the California Attorney General for additional information. On March 20, 2009, a qui tam lawsuit, California ex rel. Hunter Laboratories, LLC et al. v. Quest Diagnostics Incorporated, et al., which was joined by the California Attorney General and to which the previous subpoena related, was unsealed. The lawsuit was brought against the Company and several other major laboratories operating in California and alleges that the defendants improperly billed the state Medicaid program and, therefore, violated the California False Claims Act. The lawsuit seeks actual and treble damages and civil penalties for each alleged false claim, as well as recovery of costs, attorney’s fees, and expenses. The original complaint was dismissed on the basis of (i) misjoinder and (ii) lack of particularity in the claims and a separate amended complaint was filed against the Company on December 14, 2009. The Company filed an answer to the new complaint on February 5, 2010. The Company participated in mediation on December 6, 2010 and February 10, 2011. The case is currently scheduled for trial on January 30, 2012.

During the third quarter of 2010, the Company responded to an audit from the California Department of Health Care Services (“DHCS”) of one of the Company’s California laboratories for the period of January 1, 2010 through June 30, 2010. DHCS subsequently indicated that this laboratory charged the Medi-Cal program more than what was charged to other payers for some lab services and that this is inconsistent with DHCS’s current interpretation of California regulations. DHCS provided the Company with a proposed agreement related to the Company’s billing to the Medi-Cal program, including a requirement that the Company charge Medi-Cal the “lowest price” it charges others for a particular laboratory test. The Company disagrees with DHCS’ contentions and interpretation of its regulations and believes that it has properly charged the Medi-Cal program under all applicable laws and regulations. The Company has subsequently received a self-audit letter and a similar audit request relating to another Company laboratory. The Company is continuing to cooperate with DHCS with respect to the audits.

In addition, the Company has received three other subpoenas since 2007 related to Medicaid billing. In June 2010, the Company received a subpoena from the State of Florida requesting documents related to its billing to Florida Medicaid. In February 2009, the Company received a subpoena from the Commonwealth of Virginia seeking documents related to the Company’s billing for state Medicaid. In October 2009, the Company received a subpoena from the State of Michigan seeking documents related to its billing to Michigan Medicaid. The Company also responded to an October 2007 subpoena from the United States Office of Inspector General’s regional office in New York and a September 2009 subpoena from the United States Office of Inspector General’s regional office in Massachusetts regarding certain of its billing practices. The Company is cooperating with the requests.

On August 19, 2010, Aetna, Inc., Aetna Health Holdings, LLC and Aetna Health Management, LLC filed a lawsuit against Laboratory Corporation of America Holdings in the United States District Court for the Eastern District of Pennsylvania, alleging unfair competition, misrepresentation, interference and breach of contract, and violation of trade secret laws. Aetna is seeking unspecified monetary damages and equitable relief. The Company intends to vigorously defend the lawsuit.

The Company acquired certain assets of Westcliff Medical Laboratories (“Westcliff”) on June 16, 2010. On June 25, 2010, the Company and the Federal Trade Commission (“FTC”) entered into a letter agreement (“Agreement”) whereby the Company agreed to hold the Westcliff business separate and independent of the Company from the date the Company acquired the Westcliff assets until the Agreement was set to terminate on December 3, 2010. The Company subsequently responded to a subpoena and Civil Investigative Demand from the FTC regarding the acquisition. On December 1, 2010, the FTC issued an administrative complaint challenging the Westcliff acquisition (“Administrative Proceeding”). A hearing in the Administrative Proceeding before an FTC administrative law judge is scheduled to begin on May 2, 2011, in Washington, DC and the Company intends to vigorously defend itself in that proceeding. On December 1, 2010, the FTC also filed an action in federal court in the District of Columbia seeking a temporary restraining order and preliminary injunction to prevent the Company from integrating the Westcliff assets upon the expiration of the Agreement. The Company successfully moved for transfer of the federal district court matter to the United States District Court for the Central District of California, and the Company voluntarily agreed to extend the Agreement until the federal district court ruled on the FTC’s request for a preliminary injunction. On February 22, 2011 the federal district court denied the preliminary injunction and dissolved the temporary restraining order, allowing the Company to integrate the Westcliff assets into its business operations. On February 23, 2011 the FTC filed a notice of appeal to the Ninth Circuit Court of Appeals and a motion with the federal district court requesting a preliminary injunction maintaining the Agreement pending a decision from that appeal. The Company will vigorously defend itself in those proceedings.

Several of these matters are in their early stages of development and management cannot predict the outcome of such matters. In the opinion of management, the ultimate disposition of such matters is not expected to have a material adverse effect on the financial position of the Company but may be material to the Company’s results of operations or cash flows in the period in which such matters are finally determined or resolved.

The Company is involved from time to time in various claims and legal actions, including arbitrations, class actions, and other litigation, arising in the ordinary course of business. Some of these actions involve claims that are substantial in amount. These matters include, but are not limited to, intellectual property disputes, professional liability, employee related matters, and inquiries, including subpoenas and other civil investigative demands, from governmental agencies and Medicare or Medicaid payers and managed care payers reviewing billing practices or requesting comment on allegations of billing irregularities that are brought to their attention through billing audits or third parties. The Company receives civil investigative demands or other inquiries from various governmental bodies in the ordinary course of its business. Such inquiries can relate to the Company or other healthcare providers. The Company works cooperatively to respond to appropriate requests for information.

The Company is also named from time to time in suits brought under the qui tam provisions of the False Claims Act and comparable state laws. These suits typically allege that the Company has made false statements and/or certifications in connection with claims for payment from federal or state health care programs. They may remain under seal (hence, unknown to the Company) for some time while the government decides whether to intervene on behalf of the qui tam plaintiff. Such claims are an inevitable part of doing business in the health care field today.

The Company believes that it is in compliance in all material respects with all statutes, regulations and other requirements applicable to its clinical laboratory operations. The clinical laboratory testing industry is, however, subject to extensive regulation, and the courts have not interpreted many of these statutes and regulations. There can be no assurance therefore that those applicable statutes and regulations will not be interpreted or applied by a prosecutorial, regulatory or judicial authority in a manner that would adversely affect the Company. Potential sanctions for violation of these statutes and regulations include significant fines and the loss of various licenses, certificates and authorizations.

Effective January 1, 2007, the Company commenced its successful implementation of its ten-year agreement with United Healthcare Insurance Company (“UnitedHealthcare”) and became its exclusive national laboratory provider. During the first three years of the ten-year agreement, the Company committed to reimburse UnitedHealthcare up to $200.0 for transition costs related to developing expanded networks in defined markets during the first three years of the agreement. At the end of the reimbursement period, approximately $119.6 of such transition payments have been billed to the Company by UnitedHealthcare and approximately $119.6 has been remitted by the Company. UnitedHealthcare has indicated that there will be no further billings. The Company is amortizing the total transition costs over the life of the contract.

Under the Company's present insurance programs, coverage is obtained for catastrophic exposure as well as those risks required to be insured by law or contract. The Company is responsible for the uninsured portion of losses related primarily to general, professional and vehicle liability, certain medical costs and workers' compensation. The self-insured retentions are on a per occurrence basis without any aggregate annual limit. Provisions for losses expected under these programs are recorded based upon the Company's estimates of the aggregated liability of claims incurred. At December 31, 2010, the Company had provided letters of credit aggregating approximately $37.4, primarily in connection with certain insurance programs. The Company’s availability under its Revolving Facility is reduced by the amount of these letters of credit.

The Company leases various facilities and equipment under non-cancelable lease arrangements. Future minimum rental commitments for leases with non-cancelable terms of one year or more at December 31, 2010 are as follows:

	Operating
2011	$	148.4
2012		112.1
2013		73.6
2014		50.6
2015		29.0
Thereafter		74.2
Total minimum lease payments		487.9
Less:
Amounts included in restructuring and acquisition related accruals		(6.9	)
Non-cancelable sub-lease income		(0.2	)
Total minimum operating lease payments	$	480.8

Rental expense, which includes rent for real estate, equipment and automobiles under operating leases, amounted to $202.1, $182.9 and $175.1 for the years ended December 31, 2010, 2009 and 2008, respectively.

At December 31, 2010, the Company was a guarantor on approximately $1.6 of equipment leases. These leases were entered into by a joint venture in which the Company owns a 50% interest and have a remaining term of approximately two years.

PENSION AND POSTRETIREMENT PLANS

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Pension And Postretirement Plans

16. PENSION AND POSTRETIREMENT PLANS

Pension Plans

In October 2009, the Company received approval from its Board of Directors to freeze any additional service-based credits for any years of service after December 31, 2009 on the defined benefit retirement plan (the "Company Plan") and the nonqualified supplemental retirement plan (the “PEP”). Both plans have been closed to new participants. Employees participating in the Company Plan and the PEP no longer earn service-based credits, but continue to earn interest credits. In addition, effective January 1, 2010, all employees eligible for the defined contribution retirement plan (the “401K Plan”) receive a minimum 3% non-elective contribution (“NEC”) concurrent with each payroll period. The NEC replaces the Company match, which has been discontinued. Employees are not required to make a contribution to the 401K Plan to receive the NEC. The NEC is non-forfeitable and vests immediately. The 401K Plan also permits discretionary contributions by the Company of 1% to 3% of pay for eligible employees based on service.

The Company believes these changes to the Company Plan, the PEP and its 401K Plan align the Company’s retirement plan strategy with prevailing industry practices and reduce the impact of market volatility on the Company Plan.

The Company’s 401K Plan covers substantially all employees. Prior to 2010, Company contributions to the plan were based on a percentage of employee contributions. In 2010, the Company made non-elective and discretionary contributions to the plan. The cost of this plan was $40.6, $15.2 and $15.5 in 2010, 2009 and 2008, respectively. The increase in 401K costs and contributions was due to the non-elective and discretionary contributions made by the Company in 2010.

In addition, the Company Plan covers substantially all employees hired prior to December 31, 2009. The benefits to be paid under the Company Plan are based on years of credited service through December 31, 2009, interest credits and average compensation. The Company’s policy is to fund the Company Plan with at least the minimum amount required by applicable regulations. The Company made contributions to the Company Plan of $0.0, $54.8 and $0.0 in 2010, 2009 and 2008, respectively.

The PEP covers the Company’s senior management group. Prior to 2010, the PEP provided for the payment of the difference, if any, between the amount of any maximum limitation on annual benefit payments under the Employee Retirement Income Security Act of 1974 and the annual benefit that would be payable under the Company Plan but for such limitation. Effective January 1, 2010, employees participating in the PEP no longer earn service-based credits. The PEP is an unfunded plan.

As a result of the changes to the Company Plan and PEP which were adopted in the fourth quarter of 2009, the Company recognized a net curtailment charge of $2.8 due to remeasurement of the PEP obligation at December 31, 2009 and the acceleration of unrecognized prior service for that plan. Projected pension expense for the Company Plan and the PEP is expected to decrease from $9.6 in 2010 to $8.9 in 2011. In addition, the Company does not plan to make contributions to the Company Plan during 2011.

The effect on operations for both the Company Plan and the PEP are summarized as follows:

	Year ended December 31,
	2010			2009			2008
Service cost for benefits earned	$	2.6		$	20.8		$	20.0
Interest cost on benefit obligation		18.1			18.3			17.2
Expected return on plan assets		(18.5	)		(17.3	)		(22.2	)
Net amortization and deferral		7.4			12.0			2.8
Curtailment cost		--			2.8			--
Executive retirement charge		--			--			1.7
Defined benefit plan costs	$	9.6		$	36.6		$	19.5

Amounts included in accumulated other comprehensive earnings consist of unamortized net loss of $109.3. The accumulated other comprehensive earnings that are expected to be recognized as components of the defined benefit plan costs during 2011 are $7.8 related to amortization of net loss.

A summary of the changes in the projected benefit obligations of the Company Plan and the PEP are summarized as follows:

	2010			2009
Balance at January 1	$	328.0		$	292.7
Service cost		2.6			20.8
Interest cost		18.1			18.3
Actuarial loss		24.8			24.1
Amendments		--			0.9
Benefits and administrative expenses paid		(25.3	)		(24.1	)
Plan curtailment		--			(4.7	)
Balance at December 31	$	348.2		$	328.0

The Accumulated Benefit Obligation was $348.2 and $328.0 at December 31, 2010 and 2009, respectively.

A summary of the changes in the fair value of plan assets follows:

	2010			2009
Fair value of plan assets at beginning of year	$	259.3		$	170.1
Actual return on plan assets		29.3			57.4
Employer contributions		1.1			55.9
Benefits and administrative expenses paid		(25.3	)		(24.1	)
Fair value of plan assets at end of year	$	264.4		$	259.3

Weighted average assumptions used in the accounting for the Company Plan and the PEP are summarized as follows:

	2010			2009			2008
Discount rate		5.1	%		5.8	%		6.5	%
Compensation increases		--	%		--	%		3.5	%
Expected long term rate of return		7.5	%		7.5	%		8.5	%

The Company maintains an investment policy for the management of the Company Plan’s assets. The objective of this policy is to build a portfolio designed to achieve a balance between investment return and asset protection by investing in equities of high quality companies and in high quality fixed income securities which are broadly balanced and represent all market sectors. The target allocations for plan assets are 55% equity securities, 40% fixed income securities and 5% in other assets. Equity securities primarily include investments in large-cap, mid-cap and small-cap companies located in the United States and to a lesser extent international equities in developed and emerging countries. Fixed income securities primarily include U.S. Treasury securities, mortgage-backed bonds and corporate bonds of companies from diversified industries. Other assets include investments in commodities. The weighted average expected long-term rate of return for the Company Plan’s assets is as follows:

				Weighted
				Average
				Expected
				Long-Term
	Target			Rate
	Allocation			of Return
Equity securities		55.0	%		5.0	%
Fixed income securities		40.0	%		2.0	%
Other assets		5.0	%		0.5	%

The fair values of the Company Plan’s assets at December 31, 2010 and 2009, by asset category are as follows:

	Fair value		Fair Value Measurements as of
	as of		December 31, 2010
	December 31,		Using Fair Value Hierarchy
Asset Category	2010		Level 1		Level 2		Level 3

Cash	$	2.3	$	2.3	$	--	$	--
Equity securities:
U.S. large cap - blend (a)		62.7		--		62.7		--
U.S. mid cap - blend (b)		26.7		--		26.7		--
U.S. small cap - blend (c)		9.8		--		9.8		--
International - developed		37.5		--		37.5		--
International - emerging		8.2		--		8.2		--
Commodities index (d)		15.0		--		15.0		--
Fixed income securities:
U.S. fixed income (e)		102.2		--		102.2		--
Total fair value of the Company Plan’s assets	$	264.4	$	2.3	$	262.1	$	--

	Fair value		Fair Value Measurements as of
	as of		December 31, 2009
	December 31,		Using Fair Value Hierarchy
Asset Category	2009		Level 1		Level 2		Level 3

Cash	$	13.8	$	13.8	$	--	$	--
Equity securities:
U.S. large cap - blend (a)		80.5		--		80.5		--
U.S. small cap - blend (c)		23.3		--		23.3		--
International - developed		32.5		--		32.5		--
International - emerging		7.1		--		7.1		--
Fixed income securities:
U.S. fixed income (e)		102.1		--		102.1		--
Total fair value of the Company Plan’s assets	$	259.3	$	13.8	$	245.5	$	--

a)	This category represents an equity index fund not actively managed that tracks the S&P 500.
b)	This category represents an equity index fund not actively managed that tracks the S&P mid-cap 400.
c)	This category represents an equity index fund not actively managed that tracks the Russell 2000.
d)	This category represents a commodities index fund not actively managed that tracks the Dow Jones - UBS Commodity Index.
e)	This category primarily represents a bond index fund not actively managed that tracks the Barclays Capital U.S. Aggregate Index.

The following assumed benefit payments under the Company Plan and PEP, which were used in the calculation of projected benefit obligations, are expected to be paid as follows:

2011	$	23.2
2012		22.6
2013		22.9
2014		22.7
2015		23.3
Years 2016-2020		119.7

Post-retirement Medical Plan

The Company assumed obligations under a subsidiary's post-retirement medical plan. Coverage under this plan is restricted to a limited number of existing employees of the subsidiary. This plan is unfunded and the Company’s policy is to fund benefits as claims are incurred. The effect on operations of the post-retirement medical plan is shown in the following table:

	Year ended December 31,
	2010			2009			2008
Service cost for benefits earned	$	0.3		$	0.3		$	0.4
Interest cost on benefit obligation		2.3			2.3			2.7
Net amortization and deferral		(0.9	)		(1.7	)		(1.7	)
Post-retirement medical plan costs	$	1.7		$	0.9		$	1.4

Amounts included in accumulated other comprehensive earnings consist of unamortized net gain of $4.3. The accumulated other comprehensive earnings that are expected to be recognized as components of the post-retirement medical plan costs during 2011 are ($0.1) related to amortization of net gain.

A summary of the changes in the accumulated post-retirement benefit obligation follows:

	2010			2009
Balance at January 1	$	39.6		$	36.7
Service cost for benefits earned		0.3			0.3
Interest cost on benefit obligation		2.3			2.3
Participants contributions		0.4			0.4
Actuarial loss		0.8			1.4
Benefits paid		(1.4	)		(1.5	)
Balance at December 31	$	42.0		$	39.6

The weighted-average discount rates used in the calculation of the accumulated post-retirement benefit obligation was 5.4% and 6.0% as of December 31, 2010 and 2009, respectively. The health care cost trend rate was assumed to be 7.5% and 8.0% as of December 31, 2010 and 2009, respectively, declining gradually to 5.0% in the year 2016. The health care cost trend rate has a significant effect on the amounts reported. The impact of a percentage point change each year in the assumed health care cost trend rates would change the accumulated post-retirement benefit obligation as of December 31, 2010 by an increase of $5.9 or a decrease of $4.9. The impact of a percentage point change on the aggregate of the service cost and interest cost components of the 2010 post-retirement benefit costs results in an increase of $0.4 or decrease of $0.3.

The following assumed benefit payments under the Company's post-retirement benefit plan, which reflect expected future service, as appropriate, and were used in the calculation of projected benefit obligations, are expected to be paid as follows:

2011	$	1.7
2012		1.7
2013		1.8
2014		1.9
2015		2.1
Years 2016-2020		12.3

- Definition

Description containing the entire pension and other postretirement benefits disclosure as a single block of text.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 158

-Paragraph 7, 21, 22

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5, 6, 7, 8

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 8

-Subparagraph m

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 106

-Paragraph 518

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 264

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph b

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph a

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph h

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph q

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS106-2

-Paragraph 20, 21, 22

Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 03-2

-Paragraph 8

Reference 12: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 30

-Paragraph 26

Reference 13: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Implementation Guide (Q and A)

-Number FAS88

-Paragraph 63

+ Details

FAIR VALUE MEASUREMENTS

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Fair Value Measurements

17. FAIR VALUE MEASUREMENTS

The Company’s population of financial assets and liabilities subject to fair value measurements as of December 31, 2010 and 2009 are as follows:

	Fair value		Fair Value Measurements as of
	as of		December 31, 2010
	December 31,		Using Fair Value Hierarchy
	2010		Level 1		Level 2		Level 3
Noncontrolling interest puts	$	168.7	$	--	$	168.7	$	--

Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	$	--	$	--	$	--	$	--
Interest rate swap liability		2.4		--		2.4		--
Total fair value of derivatives	$	2.4	$	--	$	2.4	$	--

	Fair value		Fair Value Measurements as of
	as of		December 31, 2009
	December 31,		Using Fair Value Hierarchy
	2009		Level 1		Level 2		Level 3
Noncontrolling interest put	$	142.4	$	--	$	142.4	$	--

Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	$	--	$	--	$	--	$	--
Interest rate swap liability		10.6		--		10.6		--
Total fair value of derivatives	$	10.6	$	--	$	10.6	$	--

The noncontrolling interest puts are valued at their contractually determined values, which approximate fair values. The fair values for the embedded derivatives and interest rate swap are based on observable inputs or quoted market prices from various banks for similar instruments.

The carrying amounts of cash and cash equivalents, accounts receivable, income taxes receivable, and accounts payable are considered to be representative of their respective fair values due to their short-term nature. The fair market value of the zero-coupon subordinated notes, based on market pricing, was approximately $419.5 and $374.6 as of December 31, 2010 and 2009, respectively. The fair market value of the senior notes, based on market pricing, was approximately $1,549.8 and $645.2 as of December 31, 2010 and 2009, respectively. As of December 31, 2010 and 2009, the estimated fair market value of the Company’s variable rate debt of $370.1 and $486.4, respectively, was estimated by calculating the net present value of related cash flows, discounted at current market rates.

- Definition

This item represents the complete disclosure regarding the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the Company is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risk is are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References+ Details

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Derivative Instruments And Hedging Activities

18. DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES

The Company addresses its exposure to market risks, principally the market risk associated with changes in interest rates, through a controlled program of risk management that includes, from time to time, the use of derivative financial instruments such as interest rate swap agreements (see Interest Rate Swap section below). Although the Company’s zero-coupon subordinated notes contain features that are considered to be embedded derivative instruments (see Embedded Derivative section below), the Company does not hold or issue derivative financial instruments for trading purposes. The Company does not believe that its exposure to market risk is material to the Company’s financial position or results of operations.

Interest Rate Swap

The Company has an interest rate swap agreement with a remaining term of approximately two years to hedge variable interest rate risk on the Company’s variable interest rate term loan. On a quarterly basis under the swap, the Company pays a fixed rate of interest (2.92%) and receives a variable rate of interest based on the three-month LIBOR rate on an amortizing notional amount of indebtedness equivalent to the term loan balance outstanding. The swap has been designated as a cash flow hedge. Accordingly, the Company recognizes the fair value of the swap in the consolidated balance sheets and any changes in the fair value are recorded as adjustments to accumulated other comprehensive income (loss), net of tax. The fair value of the interest rate swap agreement is the estimated amount that the Company would pay or receive to terminate the swap agreement at the reporting date. The fair value of the swap was a liability of $2.4 and $10.6 at December 31, 2010 and 2009, respectively, and is included in other liabilities in the consolidated balance sheets.

Embedded Derivatives Related to the Zero-Coupon Subordinated Notes

The Company’s zero-coupon subordinated notes contain the following two features that are considered to be embedded derivative instruments under authoritative guidance in connection with accounting for derivative instruments and hedging activities:

The Company will pay contingent cash interest on the zero-coupon subordinated notes after September 11, 2006, if the average market price of the notes equals 120% or more of the sum of the issue price, accrued original issue discount and contingent additional principal, if any, for a specified measurement period.

2)	Holders may surrender zero-coupon subordinated notes for conversion during any period in which the rating assigned to the zero-coupon subordinated notes by Standard & Poor’s Ratings Services is BB- or lower.

The Company believes these embedded derivatives had no fair value at December 31, 2010 and 2009. These embedded derivatives also had no impact on the consolidated statements of operations for the years ended December 31, 2010, 2009 and 2008.

The following table summarizes the fair value and presentation in the consolidated balance sheets for derivatives designated as hedging instruments (interest rate swap liability derivative) as of December 31, 2010 and 2009, respectively:

	Fair Value as of
	December 31,
Balance Sheet Location	2010		2009
Other liabilities	$	2.4	$	10.6

The following table summarizes the effect of the interest rate swap on other comprehensive income for the years ended December 31, 2010 and 2009:

		2010				2009
Effective portion of derivative gain		$	8.2			$	2.9

EXECUTIVE RETIREMENT	12 Months Ended
EXECUTIVE RETIREMENT	Dec. 31, 2010
Notes To Financial Statements [Abstract]
EXECUTIVE RETIREMENT	19. EXECUTIVE RETIREMENT In October 2008, the Company announced the retirement of its Executive Vice President, Corporate Affairs (“EVP”), Bradford T. Smith, effective December 31, 2008. During the fourth quarter of 2008, the Company recorded charges of approximately $3.7, which included $2.0 related to the acceleration of the recognition of stock compensation and $1.7 related to the acceleration of certain defined benefit plan obligations. Following the announcement of his retirement as EVP, Mr. Smith entered into a consulting agreement with the Company effective January 1, 2009. The agreement provided for additional services to be provided by Mr. Smith following the termination of his employment as EVP to assist the Company during a transition period. Mr. Smith was Vice Chairman of the Board through the annual meeting of shareholders in May 2009. For purposes of calculating pension benefits, the agreement provided for an unreduced pension benefit, starting at age 55.

SUPPLEMENTAL CASH FLOW INFORMATION

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

SUPPLEMENTAL CASH FLOW INFORMATION

20. SUPPLEMENTAL CASH FLOW INFORMATION


	Years Ended December 31,
	2010			2009		2008

Supplemental schedule of cash flow information:
Cash paid during period for:
Interest	$	55.5		$	50.7	$	56.1
Income taxes, net of refunds		355.0			304.1		211.8
Disclosure of non-cash financing and investing activities:
Surrender of restricted stock awards and performance shares		2.4			2.7		32.7
Accrued repurchases of common stock		(0.5	)		0.5		(3.0	)
Purchase of equipment in accrued expenses		--			2.8		--

QUARTERLY DATA (UNAUDITED)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Quarterly Financial Information

21. QUARTERLY DATA (UNAUDITED)

The following is a summary of unaudited quarterly data:

	Year ended December 31, 2010
	1st		2nd		3rd		4th		Full
	Quarter		Quarter		Quarter		Quarter		Year

Net sales	$	1,193.6	$	1,238.4	$	1,276.5	$	1,295.4	$	5,003.9
Gross profit		506.9		533.6		527.7		529.6		2,097.8
Net earnings attributable to Laboratory
Corporation of America Holdings		132.7		153.7		140.0		131.8		558.2

Basic earnings per common share		1.27		1.48		1.37		1.29		5.42
Diluted earnings per common share		1.25		1.46		1.34		1.26		5.29

	Year ended December 31, 2009
	1st		2nd		3rd		4th		Full
	Quarter		Quarter		Quarter		Quarter		Year

Net sales	$	1,155.7	$	1,188.8	$	1,185.1	$	1,165.1	$	4,694.7
Gross profit		489.4		507.4		498.1		476.0		1,970.9
Net earnings attributable to Laboratory
Corporation of America Holdings		132.8		136.4		131.4		142.7		543.3

Basic earnings per common share		1.23		1.26		1.22		1.35		5.06
Diluted earnings per common share		1.22		1.24		1.21		1.33		4.98

- Definition

This element can be used to disclose the entire quarterly financial data disclosure in the annual financial statements as a single block of text. The disclosure includes a tabular presentation of financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income (loss) before extraordinary items and cumulative effect of a change in accounting principle and earnings per share data. It also includes an indication if the information in the note is unaudited, comments on the aggregate effect of year-end adjustments, and an explanation of matters or transactions that affect comparability or are pertinent to an understanding of the information furnished. Alternatively, the details of this disclosure can be reported using the elements in this group, or by using other taxonomy elements and applying the appropriate quarterly date and period contexts when creating an instance document. For example, the element for "Interest and Dividend Income, Operating" may be used by financial institutions from the Statement of Income, applying the appropriate quarterly date and period context when creating an instance document.

+ References+ Details

Schedule II - Valuation And Qualifying Accounts And Reserves

12 Months Ended

Dec. 31, 2010

Schedule to Financial Statments [Abstract]

Schedule II - Valuation and Qualifying Accounts

Schedule II


			Additions
	Balance		Charged		Additions			(1)
	at		to		as a		Other			Balance
	beginning		Costs and		Result of		(Deductions)			at end
	of year		Expense		Acquisitions		Additions			of year

Year ended December 31, 2010:
Applied against asset accounts:

Allowance for
doubtful accounts	$	173.1	$	241.5	$	--	$	(265.4	)	$	149.2

Valuation allowance-
deferred tax assets	$	3.9	$	7.7	$	--	$	(0.2	)	$	11.4

Year ended December 31, 2009:
Applied against asset accounts:

Allowance for
doubtful accounts	$	161.0	$	248.9	$	4.8	$	(241.6	)	$	173.1

Valuation allowance-
deferred tax assets	$	3.9	$	--	$	--	$	--		$	3.9

Year ended December 31, 2008:
Applied against asset accounts:

Allowance for
doubtful accounts	$	92.5	$	283.3	$	5.9	$	(220.7	)	$	161.0

Valuation allowance-
deferred tax assets	$	3.9	$	--	$	--	$	--		$	3.9

(1) Other (Deductions) Additions consists primarily of write-offs of accounts receivable amounts.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Basis of Financial Statement Presentation

Basis of Financial Statement Presentation:

Revenue Recognition

Revenue Recognition:

In connection with revenue arrangements with multiple deliverables, revenue is deferred until the Company can reasonably estimate when the performance obligation ceases or becomes inconsequential.

Use of Estimates

Use of Estimates:

Concentration of Credit Risk

Concentration of Credit Risk:

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable.

Accounts receivable balances (gross) from Medicare and Medicaid were $125.0 and $106.4 at December 31, 2010 and 2009, respectively.

Earnings Per Share

Earnings per Share:

Stock Compensation Plans

Stock Compensation Plans:

See note 14 for assumptions used in calculating compensation expense for the Company’s stock compensation plans.

Cash Equivalents

Cash Equivalents:

Inventories

Inventories:

Inventories, consisting primarily of purchased laboratory and client supplies, are stated at the lower of cost (first-in, first-out) or market.

Property, Plant and Equipment

Property, Plant and Equipment:

	Years
Buildings and building improvements		35
Machinery and equipment		3-10
Furniture and fixtures		5-10

Capitalized Software Costs

Capitalized Software Costs:

Long-Lived Assets

Long-Lived Assets:

Goodwill is evaluated for impairment by applying a fair value based test on an annual basis and more frequently if events or changes in circumstances indicate that the asset might be impaired.

The Company completed an annual impairment analysis of its indefinite lived assets, including goodwill, and has found no instances of impairment as of December 31, 2010.

Intangible Assets

Intangible Assets:

Debt Issuance Costs

Debt Issuance Costs:

The costs related to the issuance of debt are capitalized and amortized to interest expense using the effective interest method over the terms of the related debt.

Professional Liability

Professional Liability:

Income Taxes

Income Taxes:

Derivative Financial Instruments

Derivative Financial Instruments:

Fair Value of Financial Instruments

Fair Value of Financial Instruments:

Research and Development

Research and Development:

The Company expenses research and development costs as incurred.

New Accounting Pronouncements

New Accounting Pronouncements:

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Reconciliation of Basic earnings per Share to Diluted Earnings per Share

The following represents a reconciliation of basic earnings per share to diluted earnings per share:

	2010						2009						2008
					Per Share						Per Share						Per Share
	Income		Shares		Amount		Income		Shares		Amount		Income		Shares		Amount
Basic earnings per share	$	558.2		103.0	$	5.42	$	543.3		107.4	$	5.06	$	464.5		109.7	$	4.23
Stock options		--		0.6				--		0.5				--		0.7
Restricted stock awards and other		--		0.3				--		0.2				--		0.3
Effect of convertible debt, net of tax		--		1.5				--		1.0				--		1.1
Diluted earnings per share	$	558.2		105.4	$	5.29	$	543.3		109.1	$	4.98	$	464.5		111.8	$	4.16

Potential common shares not included in computation of diluted earnings per share

The following table summarizes the potential common shares not included in the computation of diluted earnings per share because their impact would have been antidilutive:

	Years Ended December 31,
	2010		2009		2008
Stock options		2.7		4.6		2.4

Property, Plant and Equipment

	Years
Buildings and building improvements		35
Machinery and equipment		3-10
Furniture and fixtures		5-10

RESTRUCTURING RESERVES (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Company's Restructuring Activities

The following represents the Company’s restructuring activities for the period indicated:

	Severance			Lease
	and Other			and Other
	Employee			Facility
	Costs			Costs			Total
Balance as of December 31, 2009	$	6.6		$	19.0		$	25.6
Restructuring charges		8.0			3.1			11.1
Reduction of prior restructuring accruals		(0.6	)		(4.7	)		(5.3	)
Cash payments and other adjustments		(9.1	)		(4.5	)		(13.6	)
Balance as of December 31, 2010	$	4.9		$	12.9		$	17.8

Current							$	11.4
Non-current								6.4
							$	17.8

JOINT VENTURE PARTNERSHIPS AND EQUITY METHOD INVESTMENTS (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Investments in unconsolidated joint venture partnerships and equity method investment

At December 31, 2010 the Company had investments in the following unconsolidated joint venture partnerships and equity method investments:

	Net		Percentage
Locations	Investment		Interest Owned
Joint Venture Partnerships:
Milwaukee, Wisconsin	$	9.2		50.00	%
Alberta, Canada		60.9		43.37	%
Cincinnati, Ohio		0.0		50.00	%
Equity Method Investments:
Canada, China and Western Europe		5.4		17.50	%
Charlotte, North Carolina		3.0		50.00	%

Condensed unconsolidated financial information for joint venture partnerships and equity method investments is shown in the following table.

As of December 31:	2010		2009
Current assets	$	61.9	$	35.3
Other assets		48.4		41.4
Total assets		110.3		76.7
Current liabilities		55.6		28.0
Other liabilities		17.9		2.3
Total liabilities		73.5		30.3
Partners' equity		36.8		46.4
Total liabilities and partners’ equity	$	110.3	$	76.7

For the period January 1 - December 31:	2010		2009		2008
Net sales	$	255.5	$	212.4	$	182.0
Gross profit		73.9		69.6		69.0
Net earnings		20.0		33.3		34.3

ACCOUNTS RECEIVABLE, NET (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Accounts receivable

	December 31,			December 31,
	2010			2009
Gross accounts receivable	$	804.8		$	747.3
Less allowance for doubtful accounts		(149.2	)		(173.1	)
	$	655.6		$	574.2

PROPERTY, PLANT AND EQUIPMENT, NET (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Property, plant and equipment, net

	December 31,			December 31,
	2010			2009
Land	$	25.8		$	23.4
Buildings and building improvements		125.4			116.7
Machinery and equipment		615.7			584.8
Software		299.2			289.6
Leasehold improvements		171.6			147.0
Furniture and fixtures		51.2			48.4
Construction in progress		95.6			49.8
Equipment under capital leases		3.5			3.5
		1,388.0			1,263.2
Less accumulated depreciation and amortization of capital lease assets		(801.1	)		(762.4	)
	$	586.9		$	500.8

GOODWILL AND INTANGIBLE ASSETS (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Changes in Carrying Amount of Goodwill

The changes in the carrying amount of goodwill (net of accumulated amortization) for the years ended December 31, 2010 and 2009 are as follows:

	2010			2009
Balance as of January 1	$	1,897.1		$	1,772.2
Goodwill acquired during the year		704.4			124.1
Adjustments to goodwill		(0.2	)		0.8
Goodwill, net	$	2,601.3		$	1,897.1

Components of identifiable intangible assets

The components of identifiable intangible assets are as follows:

	December 31, 2010					December 31, 2009
	Gross					Gross
	Carrying		Accumulated			Carrying		Accumulated
	Amount		Amortization			Amount		Amortization

Customer relationships	$	1,146.0	$	(370.0	)	$	839.8	$	(337.1	)
Patents, licenses and technology		144.7		(75.7	)		119.2		(62.4	)
Non-compete agreements		26.6		(9.4	)		39.4		(30.7	)
Trade name		123.3		(50.3	)		117.7		(41.8	)
Canadian licenses		738.9		--			698.1		--
	$	2,179.5	$	(505.4	)	$	1,814.2	$	(472.0	)

Acquired amortizable intangible assets and their respective weighted average amortization periods

A summary of amortizable intangible assets acquired during 2010, and their respective weighted average amortization periods are as follows:

			Weighted
			Average
			Amortization
	Amount		Period

Customer relationships	$	319.9		19.2
Patents, licenses and technology		25.5		0.6
Non-compete agreements		12.8		0.2
Trade name		5.6		--
	$	363.8		20.0

ACCRUED EXPENSES AND OTHER (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Accrued expenses and other

	December 31,		December 31,
	2010		2009
Employee compensation and benefits	$	188.0	$	143.4
Self-insurance reserves		70.8		56.2
Accrued taxes payable		13.8		19.0
Royalty and license fees payable		12.6		6.9
Accrued repurchases of common stock		--		0.5
Restructuring reserves		11.4		15.2
Acquisition related reserves		18.4		5.6
Interest payable		13.0		8.6
Other		24.9		20.3
	$	352.9	$	275.7

OTHER LIABILITIES (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Other liabilities

	December 31,		December 31,
	2010		2009
Post-retirement benefit obligation	$	42.0	$	39.6
Defined benefit plan obligation		52.8		41.4
Restructuring reserves		6.4		10.4
Self-insurance reserves		12.1		12.1
Interest rate swap liability		2.4		10.6
Acquisition related reserves		0.6		1.1
Deferred revenue		7.2		22.5
Other		27.9		20.7
	$	151.4	$	158.4

DEBT (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Short-term borrowings and current portion of long-term debt

Short-term borrowings and current portion of long-term debt at December 31, 2010 and 2009 consisted of the following:

	December 31,		December 31,
	2010		2009
Zero-coupon convertible subordinated notes	$	286.7	$	292.2
Term loan, current		75.0		50.0
Revolving credit facility		--		75.0
Total short-term borrowings and current portion of long-term debt	$	361.7	$	417.2

Long-term debt

Long-term debt at December 31, 2010 and 2009 consisted of the following:

	December 31,		December 31,
	2010		2009
Senior notes due 2013	$	350.9	$	351.3
Senior notes due 2015		250.0		250.0
Senior notes due 2016		325.0		--
Senior notes due 2020		600.0		--
Term loan, non-current		300.0		375.0
Other long-term debt		0.8		0.9
Total long-term debt	$	1,826.7	$	977.2

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Common shares issued and outstanding [Text Block]

	2010			2009

Issued		124.5			127.4
In treasury		(22.1	)		(22.1	)
Outstanding		102.4			105.3

Changes in common shares issued and held in treasury [Text Block]

The changes in common shares issued and held in treasury are summarized below:

Common shares issued
	2010			2009			2008
Common stock issued at January 1		127.4			130.3			132.7
Common stock issued under employee stock plans		1.6			0.6			2.2
Common stock issued upon conversion of zero-coupon
subordinated notes		--			0.4			--
Retirement of common stock		(4.5	)		(3.9	)		(4.6	)
Common stock issued at December 31		124.5			127.4			130.3

Common shares held in treasury
	2010		2009		2008
Common shares held in treasury at January 1		22.1		22.1		21.7
Surrender of restricted stock and performance share awards		--		--		0.4
Common shares held in treasury at December 31		22.1		22.1		22.1

Accumulated Other Comprehensive Earnings Components [Text Block]

The components of accumulated other comprehensive earnings are as follows:

	Foreign			Net			Interest			Accumulated
	Currency			Benefit			Rate			Other
	Translation			Plan			Swap			Comprehensive
	Adjustments			Adjustments			Adjustments			Earnings
Balance at December 31, 2007	$	148.1		$	(28.1	)	$	--		$	120.0
Current year adjustments		(129.6	)		(81.0	)		(13.5	)		(224.1	)
Tax effect of adjustments		50.1			32.0			5.3			87.4
Balance at December 31, 2008		68.6			(77.1	)		(8.2	)		(16.7	)
Current year adjustments		93.3			31.5			2.9			127.7
Tax effect of adjustments		(36.1	)		(12.2	)		(1.2	)		(49.5	)
Balance at December 31, 2009		125.8			(57.8	)		(6.5	)		61.5
Current year adjustments		41.3			(8.3	)		8.2			41.2
Tax effect of adjustments		(14.3	)		3.2			(3.1	)		(14.2	)
Balance at December 31, 2010	$	152.8		$	(62.9	)	$	(1.4	)	$	88.5

- Definition

This label may include the following: 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income. Components of comprehensive income include: (1) foreign currency translation adjustments; (2) gains and losses on foreign currency transactions that are designated as, and are effective as, economic hedges of a net investment in a foreign entity; (3) gains and losses on intercompany foreign currency transactions that are of a long-term-investment nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements; (4) change in the market value of a futures contract that qualifies as a hedge of an asset reported at fair value; (5) unrealized holding gains and losses on available-for-sale securities and that resulting from transfers of debt securities from the held-to-maturity category to the available-for-sale category; (6) a net loss recognized as an additional pension liability not yet recognized as net periodic pension cost; and (7) the net gain or loss and net prior service cost or credit for pension plans and other postretirement benefit plans.

+ References+ Details

INCOME TAXES (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Income Tax Disclosure

The sources of income before taxes, classified between domestic and foreign entities are as follows:

Pre-tax income	2010		2009		2008

Domestic	$	876.1	$	848.0	$	747.8
Foreign		39.5		36.6		37.9
Total pre-tax income	$	915.6	$	884.6	$	785.7

The provisions for income taxes in the accompanying consolidated statements of operations consist of the following:

	Years Ended December 31,
	2010			2009			2008
Current:
Federal	$	269.9		$	266.2		$	188.1
State		50.4			41.0			39.8
Foreign		10.8			12.2			10.4
	$	331.1		$	319.4		$	238.3
Deferred:
Federal	$	12.2		$	25.3		$	54.0
State		(0.5	)		(15.5	)		12.8
Foreign		1.2			(0.2	)		2.8
		12.9			9.6			69.6
	$	344.0		$	329.0		$	307.9

The effective tax rates on earnings before income taxes are reconciled to statutory federal income tax rates as follows:

	Years Ended December 31,
	2010			2009			2008
Statutory federal rate		35.0	%		35.0	%		35.0	%
State and local income taxes, net of federal income tax effect		3.5			1.9			4.3
Other		(0.9	)		0.3			(0.1	)
Effective rate		37.6	%		37.2	%		39.2	%

The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are as follows:

	December 31,			December 31,
	2010			2009
Deferred tax assets:
Accounts receivable	$	2.6		$	12.1
Employee compensation and benefits		96.3			72.0
Self insurance reserves		27.1			20.2
Postretirement benefit obligation		16.3			15.4
Acquisition and restructuring reserves		10.2			11.6
Tax loss carryforwards		50.1			45.9
		202.6			177.2
Less: valuation allowance		(11.4	)		(3.9	)
Net deferred tax assets	$	191.2		$	173.3

Deferred tax liabilities:
Deferred earnings		(18.0	)		(23.1	)
Intangible assets		(343.8	)		(336.7	)
Property, plant and equipment		(63.3	)		(58.5	)
Zero-coupon subordinated notes		(145.2	)		(136.5	)
Currency translation adjustment		(94.3	)		(78.0	)
Other		(5.1	)		(2.2	)
Total gross deferred tax liabilities		(669.7	)		(635.0	)
Net deferred tax liabilities	$	(478.5	)	$	(461.7	)

The following table shows a reconciliation of the unrecognized income tax benefits from uncertain tax positions for the years ended December 31, 2010, 2009 and 2008:

	2010			2009			2008
Balance as of January 1	$	59.0		$	72.5		$	55.7
Increase in reserve for tax positions taken in the current year		9.1			10.9			13.4
Increase (decrease) in reserve for tax positions taken in a
prior period		(0.6	)		(4.2	)		5.2
Decrease in reserve as a result of settlements reached with
tax authorities		(1.3	)		(15.7	)		(0.6	)
Decrease in reserve as a result of lapses in the statute of
limitations		(12.6	)		(4.5	)		(1.2	)
Balance as of December 31	$	53.6		$	59.0		$	72.5

STOCK COMPENSATION PLANS (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Disclosure of Share Based Compensation Arrangements by Share Based Payment Awards

Changes in options outstanding under the plans for the periods indicated were as follows:

						Weighted-
				Weighted-		Average
				Average		Remaining		Aggregate
	Number of			Exercise Price		Contractual		Intrinsic
	Options			per Option		Term		Value
Outstanding at December 31, 2009		6.3		$	64.52
Granted		1.8			70.47
Exercised		(1.3	)		55.12
Cancelled		(0.2	)		71.51
Outstanding at December 31, 2010		6.6		$	67.84		7.4	$	132.3
Vested and expected to vest
at December 31, 2010		6.5		$	67.84		7.4	$	130.2
Exercisable at December 31, 2010		3.2		$	68.09		6.2	$	62.9

The following table shows the weighted average grant-date fair values of options and the weighted average assumptions that the Company used to develop the fair value estimates:

	2010			2009			2008

Fair value per option	$	14.12		$	10.85		$	13.25
Valuation assumptions
Weighted average expected life (in years)		3.1			3.0			3.2
Risk free interest rate		1.5	%		1.1	%		2.7	%
Expected volatility		0.3			0.2			0.2
Expected dividend yield		0.0	%		0.0	%		0.0	%

Restricted Stock and Performance Shares

The following table shows a summary of nonvested shares for the year ended December 31, 2010:

				Weighted-
				Average
	Number of			Grant Date
	Shares			Fair Value
Nonvested at January 1, 2010		0.5		$	69.43
Granted		0.2			70.60
Vested		(0.1	)		72.52
Nonvested at December 31, 2010		0.6			68.26

Employee Stock Purchase Plan

	2010			2009			2008

Fair value of the employee’s purchase right	$	15.39		$	14.28		$	16.10
Valuation assumptions
Risk free interest rate		0.2	%		0.2	%		1.2	%
Expected volatility		0.2			0.2			0.3
Expected dividend yield		0.0	%		0.0	%		0.0	%

Disclosure of the Impact of Stock Options Exercised

	2010		2009		2008

Cash received by the Company	$	73.7	$	14.3	$	53.6
Tax benefits realized	$	13.2	$	2.7	$	14.3
Aggregate intrinsic value	$	33.4	$	7.0	$	35.5

Schedule of Options Outstanding and Exercisable at December 31, 2010, by Range of Exercise Prices

The following table summarizes information concerning currently outstanding and exercisable options.

Options Outstanding								Options Exercisable
				Weighted Average						Weighted
				Remaining		Average				Average
Range of		Number		Contractual		Exercise		Number		Exercise
Exercise Prices		Outstanding		Life		Price		Exercisable		Price

	$ 6.80 - 59.37		0.9		4.3		$51.41		0.9		$51.41
	$59.38 - 67.60		1.7		8.1		$60.33		0.4		$60.42
	$67.61 - 75.63		3.0		8.3		$72.67		0.9		$75.63
	$75.64 - 80.37		1.0		6.3		$80.17		1.0		$80.31
			6.6		7.4		$67.84		3.2		$68.09

COMMITMENTS AND CONTINGENT LIABILITIES (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Future minimum rental commitments

	Operating
2011	$	148.4
2012		112.1
2013		73.6
2014		50.6
2015		29.0
Thereafter		74.2
Total minimum lease payments		487.9
Less:
Amounts included in restructuring and acquisition related accruals		(6.9	)
Non-cancelable sub-lease income		(0.2	)
Total minimum operating lease payments	$	480.8

- Definition

General description of lessee's leasing arrangements including: (1) The basis on which contingent rental payments are determined, (2) The existence and terms of renewal or purchase options and escalation clauses, (3) Restrictions imposed by lease arrangements, such as those concerning dividends, additional debt, and further leasing, (4) Rent holidays, rent concessions, or leasehold improvement incentives and unusual provisions or conditions. Disclosure may also include the specific period used to amortize material leasehold improvements made at the inception of the lease or during the lease term. Additionally, for operating leases having initial or remaining noncancelable lease terms in excess of one year: (a) future minimum rental payments required as of the date of the latest balance sheet presented, in the aggregate and for each of the five succeeding fiscal years, (b) the total of minimum rentals to be received in the future under noncancelable subleases as of the date of the latest balance sheet presented, and (c) for all operating leases, rental expense for each period for which an income statement is presented, with separate amounts for minimum rentals, contingent rentals, and sublease rentals. Rental payments under leases with terms of a month or less that were not renewed need not be included.

+ References+ Details

PENSION AND POSTRETIREMENT PLANS (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Schedule Of Pension and Postrtirement Plans

The effect on operations for both the Company Plan and the PEP are summarized as follows:

	Year ended December 31,
	2010			2009			2008
Service cost for benefits earned	$	2.6		$	20.8		$	20.0
Interest cost on benefit obligation		18.1			18.3			17.2
Expected return on plan assets		(18.5	)		(17.3	)		(22.2	)
Net amortization and deferral		7.4			12.0			2.8
Curtailment cost		--			2.8			--
Executive retirement charge		--			--			1.7
Defined benefit plan costs	$	9.6		$	36.6		$	19.5

A summary of the changes in the projected benefit obligations of the Company Plan and the PEP are summarized as follows:

	2010			2009
Balance at January 1	$	328.0		$	292.7
Service cost		2.6			20.8
Interest cost		18.1			18.3
Actuarial loss		24.8			24.1
Amendments		--			0.9
Benefits and administrative expenses paid		(25.3	)		(24.1	)
Plan curtailment		--			(4.7	)
Balance at December 31	$	348.2		$	328.0

The Accumulated Benefit Obligation was $348.2 and $328.0 at December 31, 2010 and 2009, respectively.

A summary of the changes in the fair value of plan assets follows:

	2010			2009
Fair value of plan assets at beginning of year	$	259.3		$	170.1
Actual return on plan assets		29.3			57.4
Employer contributions		1.1			55.9
Benefits and administrative expenses paid		(25.3	)		(24.1	)
Fair value of plan assets at end of year	$	264.4		$	259.3

Weighted average assumptions used in the accounting for the Company Plan and the PEP are summarized as follows:

	2010			2009			2008
Discount rate		5.1	%		5.8	%		6.5	%
Compensation increases		--	%		--	%		3.5	%
Expected long term rate of return		7.5	%		7.5	%		8.5	%

				Weighted
				Average
				Expected
				Long-Term
	Target			Rate
	Allocation			of Return
Equity securities		55.0	%		5.0	%
Fixed income securities		40.0	%		2.0	%
Other assets		5.0	%		0.5	%

Post-retirement Medical Plan

	Year ended December 31,
	2010			2009			2008
Service cost for benefits earned	$	0.3		$	0.3		$	0.4
Interest cost on benefit obligation		2.3			2.3			2.7
Net amortization and deferral		(0.9	)		(1.7	)		(1.7	)
Post-retirement medical plan costs	$	1.7		$	0.9		$	1.4

A summary of the changes in the accumulated post-retirement benefit obligation follows:

	2010			2009
Balance at January 1	$	39.6		$	36.7
Service cost for benefits earned		0.3			0.3
Interest cost on benefit obligation		2.3			2.3
Participants contributions		0.4			0.4
Actuarial loss		0.8			1.4
Benefits paid		(1.4	)		(1.5	)
Balance at December 31	$	42.0		$	39.6

Plan Assets at Fair Value By Asset Category

The fair values of the Company Plan’s assets at December 31, 2010 and 2009, by asset category are as follows:

	Fair value		Fair Value Measurements as of
	as of		December 31, 2010
	December 31,		Using Fair Value Hierarchy
Asset Category	2010		Level 1		Level 2		Level 3

Cash	$	2.3	$	2.3	$	--	$	--
Equity securities:
U.S. large cap - blend (a)		62.7		--		62.7		--
U.S. mid cap - blend (b)		26.7		--		26.7		--
U.S. small cap - blend (c)		9.8		--		9.8		--
International - developed		37.5		--		37.5		--
International - emerging		8.2		--		8.2		--
Commodities index (d)		15.0		--		15.0		--
Fixed income securities:
U.S. fixed income (e)		102.2		--		102.2		--
Total fair value of the Company Plan’s assets	$	264.4	$	2.3	$	262.1	$	--

	Fair value		Fair Value Measurements as of
	as of		December 31, 2009
	December 31,		Using Fair Value Hierarchy
Asset Category	2009		Level 1		Level 2		Level 3

Cash	$	13.8	$	13.8	$	--	$	--
Equity securities:
U.S. large cap - blend (a)		80.5		--		80.5		--
U.S. small cap - blend (c)		23.3		--		23.3		--
International - developed		32.5		--		32.5		--
International - emerging		7.1		--		7.1		--
Fixed income securities:
U.S. fixed income (e)		102.1		--		102.1		--
Total fair value of the Company Plan’s assets	$	259.3	$	13.8	$	245.5	$	--

a)	This category represents an equity index fund not actively managed that tracks the S&P 500.
b)	This category represents an equity index fund not actively managed that tracks the S&P mid-cap 400.
c)	This category represents an equity index fund not actively managed that tracks the Russell 2000.
d)	This category represents a commodities index fund not actively managed that tracks the Dow Jones - UBS Commodity Index.
e)	This category primarily represents a bond index fund not actively managed that tracks the Barclays Capital U.S. Aggregate Index.

Assumed Benefit Payments By Year

The following assumed benefit payments under the Company Plan and PEP, which were used in the calculation of projected benefit obligations, are expected to be paid as follows:

2011	$	23.2
2012		22.6
2013		22.9
2014		22.7
2015		23.3
Years 2016-2020		119.7

2011	$	1.7
2012		1.7
2013		1.8
2014		1.9
2015		2.1
Years 2016-2020		12.3

FAIR VALUE MEASUREMENTS (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Population of Financial Assets and Liabilities Subject to Fair Value Measurements

The Company’s population of financial assets and liabilities subject to fair value measurements as of December 31, 2010 and 2009 are as follows:

	Fair value		Fair Value Measurements as of
	as of		December 31, 2010
	December 31,		Using Fair Value Hierarchy
	2010		Level 1		Level 2		Level 3
Noncontrolling interest puts	$	168.7	$	--	$	168.7	$	--

Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	$	--	$	--	$	--	$	--
Interest rate swap liability		2.4		--		2.4		--
Total fair value of derivatives	$	2.4	$	--	$	2.4	$	--

	Fair value		Fair Value Measurements as of
	as of		December 31, 2009
	December 31,		Using Fair Value Hierarchy
	2009		Level 1		Level 2		Level 3
Noncontrolling interest put	$	142.4	$	--	$	142.4	$	--

Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	$	--	$	--	$	--	$	--
Interest rate swap liability		10.6		--		10.6		--
Total fair value of derivatives	$	10.6	$	--	$	10.6	$	--

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Schedule of Derivative Instruments in Statement of Financial Position at Fair Value

	Fair Value as of
	December 31,
Balance Sheet Location	2010		2009
Other liabilities	$	2.4	$	10.6

Effects of Interest Rate Swap on Other Comprehensive Income

The following table summarizes the effect of the interest rate swap on other comprehensive income for the years ended December 31, 2010 and 2009:

		2010				2009
Effective portion of derivative gain		$	8.2			$	2.9

SUPPLEMENTAL CASH FLOW INFORMATION (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Supplemental Cash Flow Information


	Years Ended December 31,
	2010			2009		2008

Supplemental schedule of cash flow information:
Cash paid during period for:
Interest	$	55.5		$	50.7	$	56.1
Income taxes, net of refunds		355.0			304.1		211.8
Disclosure of non-cash financing and investing activities:
Surrender of restricted stock awards and performance shares		2.4			2.7		32.7
Accrued repurchases of common stock		(0.5	)		0.5		(3.0	)
Purchase of equipment in accrued expenses		--			2.8		--

QUARTERLY DATA (UNAUDITED) (Tables)

12 Months Ended

Dec. 31, 2010

Notes To Financial Statements [Abstract]

Quarterly data summary:

The following is a summary of unaudited quarterly data:

	Year ended December 31, 2010
	1st		2nd		3rd		4th		Full
	Quarter		Quarter		Quarter		Quarter		Year

Net sales	$	1,193.6	$	1,238.4	$	1,276.5	$	1,295.4	$	5,003.9
Gross profit		506.9		533.6		527.7		529.6		2,097.8
Net earnings attributable to Laboratory
Corporation of America Holdings		132.7		153.7		140.0		131.8		558.2

Basic earnings per common share		1.27		1.48		1.37		1.29		5.42
Diluted earnings per common share		1.25		1.46		1.34		1.26		5.29

	Year ended December 31, 2009
	1st		2nd		3rd		4th		Full
	Quarter		Quarter		Quarter		Quarter		Year

Net sales	$	1,155.7	$	1,188.8	$	1,185.1	$	1,165.1	$	4,694.7
Gross profit		489.4		507.4		498.1		476.0		1,970.9
Net earnings attributable to Laboratory
Corporation of America Holdings		132.8		136.4		131.4		142.7		543.3

Basic earnings per common share		1.23		1.26		1.22		1.35		5.06
Diluted earnings per common share		1.22		1.24		1.21		1.33		4.98

Schedule II - Valuation And Qualifying Accounts And Reserves (Tables)

12 Months Ended

Dec. 31, 2010

Schedule to Financial Statments [Abstract]

Valuation and Qualifying Accounts

Schedule II


			Additions
	Balance		Charged		Additions			(1)
	at		to		as a		Other			Balance
	beginning		Costs and		Result of		(Deductions)			at end
	of year		Expense		Acquisitions		Additions			of year

Year ended December 31, 2010:
Applied against asset accounts:

Allowance for
doubtful accounts	$	173.1	$	241.5	$	--	$	(265.4	)	$	149.2

Valuation allowance-
deferred tax assets	$	3.9	$	7.7	$	--	$	(0.2	)	$	11.4

Year ended December 31, 2009:
Applied against asset accounts:

Allowance for
doubtful accounts	$	161.0	$	248.9	$	4.8	$	(241.6	)	$	173.1

Valuation allowance-
deferred tax assets	$	3.9	$	--	$	--	$	--		$	3.9

Year ended December 31, 2008:
Applied against asset accounts:

Allowance for
doubtful accounts	$	92.5	$	283.3	$	5.9	$	(220.7	)	$	161.0

Valuation allowance-
deferred tax assets	$	3.9	$	--	$	--	$	--		$	3.9

(1) Other (Deductions) Additions consists primarily of write-offs of accounts receivable amounts.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2009	Jun. 30, 2009	Mar. 31, 2009	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Notes To Financial Statements [Abstract]
Number of primary laboratories (in number of laboratories)	51								51
Minimum number of patient service centers (in number of service centers)	1,700								1,700
Minimum number of employees (in number of employees)	31,000								31,000
Minimum number of patient specimens processed daily (in number of patient specimens)	440,000								440,000
Number of states where the Company provides clinical laboratory testing services (in number of states)	50								50
Number of Canadian provinces where the Company provides clinical laboratory testing services (in number of provinces)	3								3
Ownership percentage below which investments are generally accounted for on the cost method (in hundredths)									20.00%
Revenue from Medicare and Medicaid programs, percentage (in hundredths)									19.40%	19.10%	17.70%
Revenue from capitated agreements with certain managed care customers, percentage (in hundredths)									3.10%	3.60%	4.00%
Cash balances on deposit that exceed the balances insured by the F.D.I.C.	$ 52.2								$ 52.2
Cash equivalents	177.4								177.4
Accounts receivable balances (gross) from Medicare and Medicaid	125.0				106.4				125.0	106.4
Income [Abstract]
Net earnings, basic	131.8	140.0	153.7	132.7	142.7	131.4	136.4	132.8	558.2	543.3	464.5
Net earnings, diluted									$ 558.2	$ 543.3	$ 464.5
Shares [Abstract]
Outstanding shares, basic (in shares)									103.0	107.4	109.7
Dilutive effect of stock options (in shares)									0.6	0.5	0.7
Dilutive effect of restricted stock awards and other (in shares)									0.3	0.2	0.3
Dilutive effect of convertible debt, net of tax (in shares)									1.5	1.0	1.1
Outstanding shares, diluted (in shares)									105.4	109.1	111.8
Per Share Amount [Abstract]
Basic earnings per share (in dollars per share)	$ 1.29	$ 1.37	$ 1.48	$ 1.27	$ 1.35	$ 1.22	$ 1.26	$ 1.23	$ 5.42	$ 5.06	$ 4.23
Diluted earnings per share (in dollars per share)	$ 1.26	$ 1.34	$ 1.46	$ 1.25	$ 1.33	$ 1.21	$ 1.24	$ 1.22	$ 5.29	$ 4.98	$ 4.16
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock Options (in shares)									2.7	4.6	2.4
Property, Plant and Equipment [Line Items]
Estimated useful life of capitalized software costs (in years)									5
Minimum number of years over which customer lists are amortized (in years)									10
Maximum number of years over which customer lists are amortized (in years)									25
Minimum threshold percentage required to recognize income tax benefit (in hundredths)									50.00%
Buildings and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)									35
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life - Minimum (in years)									3
Estimated useful life - Maximum (in years)									10
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life - Minimum (in years)									5
Estimated useful life - Maximum (in years)									10

BUSINESS ACQUISITIONS (Details) In Millions, unless otherwise specified	12 Months Ended							12 Months Ended			12 Months Ended
	Dec. 31, 2010 USD ($)	Dec. 31, 2010 CAD	Dec. 31, 2009 USD ($)	Dec. 31, 2009 CAD	Dec. 31, 2008 USD ($)	Dec. 31, 2008 CAD	Oct. 28, 2010 USD ($)	Dec. 31, 2010 Senior notes due 2016 [Member] USD ($)	Dec. 31, 2010 Senior notes due 2020 [Member] USD ($)	Dec. 31, 2010 Combined Senior notes due 2016 and 2020 [Member] USD ($)	Dec. 31, 2010 Genzyme Genetics Business Acquisitions [Member] USD ($)	Dec. 31, 2010 Monogram Biosciences, Inc. Business Acquisition [Member] USD ($)	Dec. 31, 2009 Monogram Biosciences, Inc. Business Acquisition [Member] USD ($)	Dec. 31, 2010 Combined Business Acquisition [Member] USD ($)	Dec. 31, 2009 Combined Business Acquisition [Member] USD ($)	Dec. 31, 2008 Combined Business Acquisition [Member] USD ($)
Entity Acquired and Reason for Acquisition [Abstract]
Name of Acquired Entity											Genzyme Genetics		Monogram Biosciences, Inc.
Reason for Business Combination											Expand capabilities in reproductive, genetic, hematology-oncology and clinical trials central laboratory testing		Enhance the company's scientific differentiation and esoteric testing capabilities
Date of Acquisition [Abstract]
Effective Date of Acquisition											December 1, 2010		August 3, 2009
Cost of Acquired Entity [Abstract]
Acquisition of businesses, net of cash acquired											$ 925.2		$ 160.0	$ 256.1	$ 52.6	$ 203.9
Business acquisition professional fees and expenses incurred											25.7		2.7
Research and development expenses incurred												12.1	5.2
Purchase Price Allocation [Abstract]
Purchase consideration allocated to identifiable intangible assets											279.6		63.5
Weighted-average useful lives of identifiable intangible assets	20.0	20.0									23		15
Purchase consideration allocated to goodwill											537.8		83.6
Total intangible value amortizable for tax purposes											810.5
Tax related intangible value, amortization period for tax purposes (in years)											15
Business acquisition net operating loss tax assets													44.8
Business acquisition tax asset realization period													18 years
Bridge term loan credit agreement, maximum borrowing capacity							925.0
Long-term debt
Business acquisition debt securities sold								325.0	600.0	925.0
Business acquisition debt securities sold stated interest rate								3.125%	4.625%
Business acquisition debt securities sold maturity date	May 15, 2016	May 15, 2016						May 15, 2016	Nov. 15, 2020
Business acquisition financing commitment fees incurred	7.0
Noncontrolling Interest Put [Abstract]
Acquisition of additional partnership units in Ontario, Canada joint venture					140.9
Ownership interest percentage in Ontario, Canada joint venture (in hundredths)	85.60%	85.60%			85.60%	85.60%
Noncontrolling interest put in Ontario, Canada joint venture	137.5		0		0
Value of noncontrolling interest put					123.0
Number of transactions affecting ownership interest percentage in Ontario joint venture	2	2
Noncontrolling interest in Ontario, Canada joint venture	25.2
Combined contractual value of noncontrolling interest puts	143.5
Noncontrolling interest, current liability	148.1		142.4
Net sales of Ontario, Canada joint venture	280.0		247.5		249.0
Net sales of Ontario, Canada joint venture (in Canadian dollars)		288.5		281.3		264.4

RESTRUCTURING AND OTHER SPECIAL CHARGES (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Sep. 30, 2008	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Notes To Financial Statements [Abstract]
Net restructuring charges		$ 5.8	$ 13.5	$ 32.4
Restructuring charges related to severance and other employee costs		8.0	10.5	20.9
Restructuring charges related to contractual obligations associated with leased facilities and other facility related costs		3.1	12.5	13.4
Reduction in prior facility related restructuring accruals		4.7	7.3	1.2
Special charge related to write-off of development costs incurred on abandoned systems		6.2
Reduction in prior restructuring accruals		5.3	9.5	1.9
Reduction in prior employee severance benefits related restructuring accruals		0.6	2.2	0.7
Special charge related to estimated uncollectible amounts	$ 5.5

- Definition

The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

+ References+ Details

RESTRUCTURING RESERVES (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Restructuring Reserve [Line Items]
Balance, beginning of period	$ 25.6
Restructuring charges	11.1
Reduction in prior restructuring accruals	(5.3)	(9.5)	(1.9)
Cash payments and other adjustments	(13.6)
Balance, end of period	17.8	25.6
Current	11.4
Non-current	6.4
Severance and Other Employee Costs [Member]
Restructuring Reserve [Line Items]
Balance, beginning of period	6.6
Restructuring charges	8.0
Reduction in prior restructuring accruals	(0.6)
Cash payments and other adjustments	(9.1)
Balance, end of period	4.9
Lease and Other Facility Costs [Member]
Restructuring Reserve [Line Items]
Balance, beginning of period	19.0
Restructuring charges	3.1
Reduction in prior restructuring accruals	(4.7)
Cash payments and other adjustments	(4.5)
Balance, end of period	$ 12.9

JOINT VENTURE PARTNERSHIPS AND EQUITY METHOD INVESTMENTS (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Investments in unconsolidated joint venture partnerships and equity method investments Financial Statement, Reported Amounts
Percentage Interest Owned	50.00%
Joint venture partnerships and equity method investments, condensed unconsolidated financial information
Current assets	$ 61.9	$ 35.3
Other assets	48.4	41.4
Total assets	110.3	76.7
Current liabilities	55.6	28.0
Other liabilities	17.9	2.3
Total liabilities	73.5	30.3
Partners' equity	36.8	46.4
Total liabilities and partners' equity	110.3	76.7
Joint venture partnerships and equity method investments, condensed unconsolidated financial information, Income Statement
Net sales	255.5	212.4	182.0
Gross profit	73.9	69.6	69.0
Net earnings	20.0	33.3	34.3
The value of the Company's recorded investment in the Alberta partnership assigned to Canadian licenses	48.9
Milwaukee, Wisconsin [Member]
Investments in unconsolidated joint venture partnerships and equity method investments Financial Statement, Reported Amounts
Net Investment	9.2
Percentage Interest Owned	50.00%
Alberta, Canada [Member]
Investments in unconsolidated joint venture partnerships and equity method investments Financial Statement, Reported Amounts
Net Investment	60.9
Percentage Interest Owned	43.37%
Cincinnati, Ohio [Member]
Investments in unconsolidated joint venture partnerships and equity method investments Financial Statement, Reported Amounts
Net Investment	0
Percentage Interest Owned	50.00%
Canada, China and Western Europe [Member]
Investments in unconsolidated joint venture partnerships and equity method investments Financial Statement, Reported Amounts
Net Investment	5.4
Percentage Interest Owned	17.50%
Charlotte, North Carolina [Member]
Investments in unconsolidated joint venture partnerships and equity method investments Financial Statement, Reported Amounts
Net Investment	$ 3.0
Percentage Interest Owned	50.00%

ACCOUNTS RECEIVABLE, NET (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Sep. 30, 2008	Jun. 30, 2008	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Accounts receivable, net [Abstract]
Gross accounts receivable			$ 804.8	$ 747.3
Less allowance for doubtful accounts			(149.2)	(173.1)
Accounts receivable, net			655.6	574.2
Provision for doubtful accounts			241.5	248.9	232.8
Increase in provision for doubtful accounts		45.0
Special charge related to estimated uncollectible amounts	$ 5.5

PROPERTY, PLANT AND EQUIPMENT, NET (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Property, plant and equipment, net
Gross property, plant and equipment	$ 1,388.0	$ 1,263.2
Less accumulated depreciation and amortization of capital lease assets	(801.1)	(762.4)
Property, plant and equipment, net	586.9	500.8
Depreciation expense and amortization of capital lease assets	129.1	130.7	120.1
Software depreciation	32.0	34.8	33.7
Land [Member]
Property, plant and equipment, net
Gross property, plant and equipment	25.8	23.4
Buildings and Building Improvements [Member]
Property, plant and equipment, net
Gross property, plant and equipment	125.4	116.7
Machinery and Equipment [Member]
Property, plant and equipment, net
Gross property, plant and equipment	615.7	584.8
Software [Member]
Property, plant and equipment, net
Gross property, plant and equipment	299.2	289.6
Leasehold Improvements [Member]
Property, plant and equipment, net
Gross property, plant and equipment	171.6	147.0
Furniture and Fixtures [Member]
Property, plant and equipment, net
Gross property, plant and equipment	51.2	48.4
Construction in Progress [Member]
Property, plant and equipment, net
Gross property, plant and equipment	95.6	49.8
Equipment under capital leases [Member]
Property, plant and equipment, net
Gross property, plant and equipment	$ 3.5	$ 3.5

GOODWILL AND INTANGIBLE ASSETS (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Goodwill [Roll Forward]
Balance as of January 1	$ 1,897.1	$ 1,772.2
Goodwill acquired during the year	704.4	124.1
Adjustments to goodwill	(0.2)	0.8
Goodwill, net	2,601.3	1,897.1	1,772.2
Identifiable intangible assets
Gross Carrying Amount	2,179.5	1,814.2
Accumulated Amortization	(505.4)	(472.0)
Acquired amortizable intangible assets and their respective weighted average amortization periods
Acquired amount	363.8
Weighted average amortization period (in years)	20.0
Intangible Assets Amortization Expense
Amortization of intangible assets	72.7	62.6	57.9
Finite-Lived Intangible Assets, Future Amortization Expense
Estimated amortization expense, 2011	85.1
Estimated amortization expense, 2012	80.4
Estimated amortization expense, 2013	74.7
Estimated amortization expense, 2014	71.9
Estimated amortization expense, 2015	68.3
Estimated amortization expense, Thereafter	554.8
Amount paid for diagnostic testing technology licensing rights	0.4	0	0.8
Canadian licenses	738.9
Customer relationships [Member]
Acquired amortizable intangible assets and their respective weighted average amortization periods
Acquired amount	319.9
Weighted average amortization period (in years)	19.2
Patents, licenses and technology [Member]
Acquired amortizable intangible assets and their respective weighted average amortization periods
Acquired amount	25.5
Weighted average amortization period (in years)	0.6
Non-compete agreements [Member]
Acquired amortizable intangible assets and their respective weighted average amortization periods
Acquired amount	12.8
Weighted average amortization period (in years)	0.2
Trade name [Member]
Acquired amortizable intangible assets and their respective weighted average amortization periods
Acquired amount	5.6
Weighted average amortization period (in years)	0
Customer relationships [Member]
Identifiable intangible assets
Gross Carrying Amount	1,146.0	839.8
Accumulated Amortization	(370.0)	(337.1)
Patents, licenses and technology [Member]
Identifiable intangible assets
Gross Carrying Amount	144.7	119.2
Accumulated Amortization	(75.7)	(62.4)
Non-compete agreements [Member]
Identifiable intangible assets
Gross Carrying Amount	26.6	39.4
Accumulated Amortization	(9.4)	(30.7)
Trade name [Member]
Identifiable intangible assets
Gross Carrying Amount	123.3	117.7
Accumulated Amortization	(50.3)	(41.8)
Canadian licenses [Member]
Identifiable intangible assets
Gross Carrying Amount	738.9	698.1
Accumulated Amortization, Indefinite-Lived Intangible Asset	$ 0	$ 0

ACCRUED EXPENSES AND OTHER (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2010	Dec. 31, 2009
Accrued expenses and other [Abstract]
Employee compensation and benefits	$ 188.0	$ 143.4
Self-insurance reserves	70.8	56.2
Accrued taxes payable	13.8	19.0
Royalty and license fees payable	12.6	6.9
Accrued repurchases of common stock	0	0.5
Restructuring reserves	11.4
Acquisition related reserves	18.4	5.6
Interest payable	13.0	8.6
Other	24.9	20.3
Total accrued expenses and other	$ 352.9	$ 275.7

OTHER LIABILITIES (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2010	Dec. 31, 2009
Notes To Financial Statements [Abstract]
Post-retirement benefit obligation	$ 42.0	$ 39.6
Defined benefit plan obligation	52.8	41.4
Restructuring reserves	6.4
Self-insurance reserves	12.1	12.1
Interest rate swap liability	2.4	10.6
Acquisition related reserves	0.6	1.1
Deferred revenue	7.2	22.5
Other	27.9	20.7
Total other liabilities	$ 151.4	$ 158.4

DEBT (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended				12 Months Ended													0 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Oct. 28, 2010	Dec. 31, 2010 Revolving facility [Member]	Dec. 31, 2009 Revolving facility [Member]	Dec. 31, 2010 Senior notes due 2013 [Member]	Dec. 31, 2009 Senior notes due 2013 [Member]	Dec. 31, 2010 Senior notes due 2015 [Member]	Dec. 31, 2009 Senior notes due 2015 [Member]	Dec. 31, 2010 Senior notes due 2016 [Member]	Dec. 31, 2010 Senior notes due 2020 [Member]	Dec. 31, 2010 Combined Senior notes due 2016 and 2020 [Member]	Dec. 31, 2010 Term loan facility [Member]	Dec. 31, 2009 Term loan facility [Member]	Dec. 31, 2010 Other long-term debt [Member]	Dec. 31, 2009 Other long-term debt [Member]	Sep. 28, 2010 Zero-coupon convertible subordinated notes [Member]	Jun. 30, 2009 Zero-coupon convertible subordinated notes [Member]	Mar. 11, 2011 Zero-coupon convertible subordinated notes [Member]	Dec. 31, 2010 Zero-coupon convertible subordinated notes [Member]	Dec. 31, 2009 Zero-coupon convertible subordinated notes [Member]	Dec. 31, 2010 Term loan facility [Member]	Dec. 31, 2009 Term loan facility [Member]	Dec. 31, 2010 Revolving facility [Member]	Dec. 31, 2009 Revolving facility [Member]
Short-term Debt
Total short-term borrowings and current portion of long-term debt	$ 361.7	$ 417.2																			$ 286.7	$ 292.2	$ 75.0	$ 50.0	$ 0	$ 75.0
Maturity date	May 15, 2016						Jan. 31, 2013		Dec. 15, 2015		May 15, 2016	Nov. 15, 2020		Oct. 26, 2012							Sep. 11, 2021	Sep. 11, 2021
Outstanding balance														375	425
Principal amount at maturity of zero-coupon subordinated notes outstanding																					354.6	368.8
Principal amount of zero-coupon subordinated notes																					1,000	1,000
Issued price per principal amount at maturity																					671.65	671.65
Annual yield to maturity																					2.00%	2.00%
Minimum contingent cash interest rate on zero-coupon subordinated notes																				0.125%
Number of trading days used to establish contingent cash interest rate on zero-coupon subordinated notes																		5
Stock conversion rate for zero-coupon subordinated notes (per thousand)																					$ 13.4108	$ 13.4108
Zero-coupon convertible subordinated notes conversion feature description																					Each one thousand dollar principal amount at maturity of the notes is convertible into 13.4108 shares of the Company's common stock, subject to adjustment in certain circumstances.	Each one thousand dollar principal amount at maturity of the notes is convertible into 13.4108 shares of the Company's common stock, subject to adjustment in certain circumstances.
Minimum number of trading days in a period the common stock sale price must meet a specified threshold to trigger conversion price (in days)																					20
Number of consecutive trading days ending on the last trading day of the preceding quarter for the common stock sale price to reach a specified threshold to trigger conversion price (in days)																					30
Common stock sales price threshold, beginning																					120.00%
Common stock sales price threshold, declining per quarter																					0.1282%
Common stock sales price threshold, ending																					110.00%
Conversion trigger price, current period (per share)																					$ 69.27
Cash purchase price per each zero-coupon subordinated note																					819.5
Date in which holders of zero-coupon subordinated notes may require the Company to purchase notes at the cash purchase price plus any accrued contingent additional principal and interest																					2011-09-11
Principal amount at maturity of zero-coupon subordinated notes, redeemed in current period																			369.5
Redeemed percentage of principal amount at maturity outstanding of the zero-coupon subordinated notes																			50.00%
Cash used for zero-coupon subordinated notes redemptions	11.4	289.4	2.1																289.4
Common stock issued upon conversion of zero-coupon subordinated notes (in shares)	0	400,000	0																		400,000
Tax benefit realized in connection with common stock issued upon conversion of zero-coupon subordinated notes																					11.3
Announcement date that zero-coupon subordinated notes may be converted into cash and common stock at the stock conversion rate																					Jan. 03, 2011
Date of the terms for the zero-coupon subordinated notes and Indenture																					Oct. 24, 2006
Zero-coupon subordinated notes exercise period, beginning																					Jan. 01, 2011
Zero-coupon subordinated notes exercise period, ending																					Mar. 31, 2011
Long-term debt
Total long-term debt	1,826.7	977.2					350.9	351.3	250.0	250.0	325.0	600.0	0	300.0	375.0	0.8	0.9
Maturity date	May 15, 2016						Jan. 31, 2013		Dec. 15, 2015		May 15, 2016	Nov. 15, 2020		Oct. 26, 2012							Sep. 11, 2021	Sep. 11, 2021
Term, years					5	5								5	5
Face amount											325.0	600.0	925.0	500.0
Outstanding balance														375	425
Interest rate (in hundredths)							5.50%	5.50%	5.625%	5.625%	3.125%	4.625%
Periodic payments, frequency							Semi-annually	Semi-annually	Semi-annually	Semi-annually	Semi-annually	Semi-annually	Semi-annually	Quarterly	Quarterly
Effective interest rate (in hundredths)														3.67%
Quarterly principal payment amount														18.8
Remaining quarterly principal payments date range, start											2011-05-15	2011-05-15	2011-05-15	2011-03-31
Remaining quarterly principal payments date range, end														2012-09-30
Principal payment at maturity, amount														243.8
Debt Instrument Offering [Abstract]
Debt offering closing date											2010-11-19	2010-11-19	2010-11-19
Net proceeds from debt offerings													915.4
Revolving credit facility
Initiation date					2007-10-26	2007-10-26
Principal amount					500.0	500.0
Balance outstanding					0	75.0
Effective interest rate					0.61%	0.58%
Periodic payments, frequency					Quarterly	Quarterly
Maturity date					2012-10-26	2012-10-26
Term, years					5	5								5	5
Senior unsecured credit facilities
Issuance date of senior unsecured credit facilities	Oct. 26, 2007
Total senior unsecured credit facilities	1,000.0
Debt covenants, maximum leverage ratio	2.5 to 1.0
Debt covenants, minimum interest coverage ratio	5.0 to 1.0
Debt covenants, maximum leverage ratio before dividend payout	2.0 to 1.0
Debt covenant compliance	In compliance
Future term loan principal repayments
2011	75.0
2012	300.0
Interest rate swap agreement
Interest rate swap agreement date	Mar. 31, 2008
Interest rate swap agreement period	three-year
Fixed interest rate related to interest rate swap agreement	2.92%
Variable interest rate related to interest rate swap agreement	three-month LIBOR
Fair value of interest rate swap	2.4	10.6
Bridge term loan credit agreement, maximum borrowing capacity				$ 925.0

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	1 Months Ended	12 Months Ended
	Jan. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Feb. 10, 2011	Dec. 31, 2007
Common shares issued and outstanding [Abstract]
Common shares issued		124.5	127.4	130.3
In Treasury		(22.1)	(22.1)	(22.1)
Outstanding		102.4	105.3
Common stock, shares authorized (in shares)		265.0
Common stock, par value per share (in dollars per share)		$ 0.10
Preferred stock, shares authorized (in shares)		30.0
Preferred stock, par value per share (in dollars per share)		$ 0.10
Rollforward of common shares issued [Abstract]
Common shares issued, beginning balance (in shares)	124.5	127.4	130.3	132.7
Common stock issued under employee stock plans (in shares)		1.6	0.6	2.2
Common stock issued upon conversion of zero-coupon subordinated notes (in shares)		0	0.4	0
Common shares repurchased (in shares)	(2.6)	(4.5)	(3.9)	(4.6)
Common shares issued, ending balance (in shares)		124.5	127.4	130.3
Rollforward of common shares held in treasury [Abstract]
Common Shares Held in Treasury, beginning balance	(22.1)	(22.1)	(22.1)	(21.7)
Surrender of restricted stock and performance share awards		0	0	(4.1)
Common Shares Held in Treasury, ending balance		(22.1)	(22.1)	(22.1)
Share repurchase program [Abstract]
Purchase of common stock		$ 337.5	$ 273.5	$ 330.6
Outstanding common stock repurchase authorization		234.3			500.0
Stockholder Rights Plan [Abstract]
Stockholder's right plan dividend number of rights per common share held		1	1	1
Number of new series of participating preferred shares purchase holder entitled, per right		0.01	0.01	0.01
Purchase price of new series of participating preferred stock, per right		400.00	400.00	400.00
Beneficial ownership percentage of entity common stock at which rights become exercisable		15.00%	15.00%	15.00%
Accumulated Other Comprehensive Earnings [Abstract]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax		152.8	125.8	68.6		148.1
Other Comprehensive Income, Foreign Currency Transaction and Translation Adjustment, before Tax		41.3	93.3	(129.6)
Other Comprehensive Income, Foreign Currency Translation Gain (Loss) Arising During Period, Tax		(14.3)	(36.1)	50.1
Accumulated Other Comprehensive Income (Loss), Defined Benefit Pension and Other Postretirement Plans, Net of Tax		(62.9)	(57.8)	(77.1)		(28.1)
Other Comprehensive Income, Defined Benefit Plan's Adjustment, before Tax		(8.3)	31.5	(81.0)
Other Comprehensive Income, Defined Benefit Plans, Tax		3.2	(12.2)	32.0
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax		(1.4)	(6.5)	(8.2)		0
Other Comprehensive Income, Derivatives Qualifying as Hedges, before Tax		8.2	2.9	(13.5)
Other Comprehensive Income, Derivatives Qualifying as Hedges, Tax Effect		(3.1)	(1.2)	5.3
Accumulated Other Comprehensive Income (Loss), Net of Tax		88.5	61.5	(16.7)		120.0
Other Comprehensive Income (Loss), before Tax		41.2	127.7	(224.1)
Other Comprehensive Income (Loss), Tax		$ (14.2)	$ (49.5)	$ 87.4

INCOME TAXES (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Pre-tax income [Abstract]
Domestic	$ 876.1	$ 848.0	$ 747.8
Foreign	39.5	36.6	37.9
Total pre-tax income	915.6	884.6	785.7
Current income taxes [Abstract]
Federal	269.9	266.2	188.1
State	50.4	41.0	39.8
Foreign	10.8	12.2	10.4
Total current income taxes	331.1	319.4	238.3
Deferred income taxes [Abstract]
Federal	12.2	25.3	54.0
State	(0.5)	(15.5)	12.8
Foreign	1.2	(0.2)	2.8
Total deferred income taxes	12.9	9.6	69.6
Total income tax provision	344.0	329.0	307.9
Tax benefit associated with option exercises from stock plans	7.8	1.1	20.9
Federal statutory tax rate reconciliation [Abstract]
Statutory federal rate (in hundredths)	35.00%	35.00%	35.00%
State and local income taxes, net of federal income tax effect (in hundredths)	3.50%	1.90%	4.30%
Other (in hundredths)	(0.90%)	0.30%	(0.10%)
Effective rate (in hundredths)	37.60%	37.20%	39.20%
Favorable tax provision adjustments relating to the resolution of certain state tax issues under audit, as well as the realization of foreign tax credits		21.5
Deferred tax assets [Abstract]
Accounts receivable	2.6	12.1
Employee compensation and benefits	96.3	72.0
Self insurance reserves	27.1	20.2
Postretirement benefit obligation	16.3	15.4
Acquisition and restructuring reserves	10.2	11.6
Tax loss carryforwards	50.1	45.9
Total deferred tax assets	202.6	177.2
Less: valuation allowance	(11.4)	(3.9)
Net deferred tax assets	191.2	173.3
Deferred tax liabilities [Abstract]
Deferred earnings	(18.0)	(23.1)
Intangible assets	(343.8)	(336.7)
Property, plant and equipment	(63.3)	(58.5)
Zero-coupon subordinated notes	(145.2)	(136.5)
Currency translation adjustment	(94.3)	(78.0)
Other	(5.1)	(2.2)
Total gross deferred tax liabilities	(669.7)	(635.0)
Net deferred tax liabilities	(478.5)	(461.7)
State tax loss carryovers	0.3
State tax loss carryovers, expiration dates	2010 through 2024
Expired state net operating losses	0.2
Foreign tax loss carryovers	7.7
Foreign tax loss carryovers, expiration dates	Indefinite carryover
Federal tax loss carryovers	42.1
Federal tax loss carryovers, expiration dates	Expiring periodically through 2028
Gross unrecognized income tax benefits	53.6	59.0	72.5
Accrued interest and penalties related to unrecognized income tax benefits	12.2	14.7
Interest and penalties expense related to unrecognized income tax benefits	4.5	5.4	4.5
Interest and penalties benefit related to unrecognized income tax benefits	5.4	4.9	1.4
Reconciliation of unrecognized tax benefits [Roll Forward]
Balance as of January 1	59.0	72.5	55.7
Increase in reserve for tax positions taken in the current year	9.1	10.9	13.4
Increase (decrease) in reserve for tax positions taken in a prior period	(0.6)	(4.2)	5.2
Decrease in reserve as a result of settlements reached with tax authorities	(1.3)	(15.7)	(0.6)
Decrease in reserve as a result of lapses in the statue of limitations	(12.6)	(4.5)	(1.2)
Balance as of December 31	53.6	59.0	72.5
Unrecognized income tax benefits that would impact effective tax rate	$ 54.6	$ 60.3

STOCK COMPENSATION PLANS (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Notes To Financial Statements [Abstract]
Shares authorized for issuance under the 2008 and 2000 Stock Incentive Plans	23.8
Shares available for grant under the Company's stock option plans	4.0
Share-based Compensation Arrangements by Share-based Payment Award
Vesting period (in years)	three years
Changes in Options Outstanding Under the Stock Incentive Plans, Additional Disclosures
Weighted-average exercise price per option, outstanding, beginning balance	$ 64.52
Weighted-average exercise price per option, outstanding, ending balance	$ 67.84	$ 64.52
Stock Options Vested and Expected to Vest at December 31, 2010
Aggregate intrinsic value, vested and expected to vest options	$ 130.2
Stock Options Exercised, Impact Disclosures
Cash received by the Company	73.7	14.3	53.6
Tax benefits realized	13.2	2.7	14.3
Aggregate intrinsic value	33.4	7.0	35.5
Options Outstanding and Exercisable at December 31, 2010, by Range of Exercise Prices
Options outstanding	6.6
Options outstanding, weighted-average remaining contractual life (in years)	7.4
Options outstanding, weighted-average exercise price	$ 67.84
Options exercisable	3.2
Options exercisable, weighted-average exercise price	$ 68.09
Fair value per option	$ 14.12	$ 10.85	$ 13.25
Stock option plan expense	20.7	18.7	17.3
Acceleration of the recognition of stock option compensation			0.8
Restricted Stock and Performance Shares
Restricted stock, vesting increment	One third increments beginning on the first anniversary of the grant
Performance share awards, vesting conditions	Three year award opportunity which is subject to certain earnings per share and revenue targets
Restricted stock and performance share compensation expense	16.1	13.6	14.0
Acceleration of the recognition of restricted stock and performance shares compensation			1.2
Unrecognized compensation cost related to nonvested restricted stock and performance share-based compensation arrangements	20.8
Unrecognized compensation cost weighted average expected future recognition period (in years)	1.8
Employee Stock Purchase Plan Disclosure
Shares of common stock authorized for issuance under the employee stock purchase plan	4.5
The employee stock purchase plan permits employees to purchase shares of common stock at a certain percentage of the market price (in hundredths)	85.00%
Number of shares purchased by eligible employees	0.2	0.2	0.2
Expense related to the Company's employee stock purchase plan	2.6	2.7	2.9
Fair value of the employee's purchase right	$ 15.39	$ 14.28	$ 16.10
Exercise Price Range 1 [Member]
Options Outstanding and Exercisable at December 31, 2010, by Range of Exercise Prices
Lower exercise price range of options outstanding, end of the period	$ 6.80
Upper exercise price range of options outstanding, end of the period	$ 59.37
Options outstanding	0.9
Options outstanding, weighted-average remaining contractual life (in years)	4.3
Options outstanding, weighted-average exercise price	$ 51.41
Options exercisable	0.9
Options exercisable, weighted-average exercise price	$ 51.41
Exercise Price Range 2 [Member]
Options Outstanding and Exercisable at December 31, 2010, by Range of Exercise Prices
Lower exercise price range of options outstanding, end of the period	$ 59.38
Upper exercise price range of options outstanding, end of the period	$ 67.60
Options outstanding	1.7
Options outstanding, weighted-average remaining contractual life (in years)	8.1
Options outstanding, weighted-average exercise price	$ 60.33
Options exercisable	0.4
Options exercisable, weighted-average exercise price	$ 60.42
Exercise Price Range 3 [Member]
Options Outstanding and Exercisable at December 31, 2010, by Range of Exercise Prices
Lower exercise price range of options outstanding, end of the period	$ 67.61
Upper exercise price range of options outstanding, end of the period	$ 75.63
Options outstanding	3.0
Options outstanding, weighted-average remaining contractual life (in years)	8.3
Options outstanding, weighted-average exercise price	$ 72.67
Options exercisable	0.9
Options exercisable, weighted-average exercise price	$ 75.63
Exercise Price Range 4 [Member]
Options Outstanding and Exercisable at December 31, 2010, by Range of Exercise Prices
Lower exercise price range of options outstanding, end of the period	$ 75.64
Upper exercise price range of options outstanding, end of the period	$ 80.37
Options outstanding	1.0
Options outstanding, weighted-average remaining contractual life (in years)	6.3
Options outstanding, weighted-average exercise price	$ 80.17
Options exercisable	1.0
Options exercisable, weighted-average exercise price	$ 80.31
Stock Options [Member]
Changes in Options Outstanding Under the Stock Incentive Plans, Additional Disclosures
Number of options outstanding, beginning balance	6.3
Number of options granted	1.8
Number of options exercised	(1.3)
Number of options cancelled	(0.2)
Number of options outstanding, ending balance	6.6	6.3
Weighted-average exercise price per option, outstanding, beginning balance	$ 64.52
Weighted-average exercise price per option granted	$ 70.47
Weighted-average exercise price per option exercised	$ 55.12
Weighted-average exercise price per option cancelled	$ 71.51
Weighted-average exercise price per option, outstanding, ending balance	$ 67.84	$ 64.52
Weighted-average remaining contractual term of options outstanding (in years)	7.40
Aggregate intrinsic value of options outstanding	132.3
Stock Options Vested and Expected to Vest at December 31, 2010
Number of options vested and expected to vest	6.5
Weighted-average exercise price per option, vested and expected to vest options	$ 67.84
Weighted-average remaining contractual term, vested and expected to vest options (in years)	7.4
Number of options exercisable	3.2
Weighted-average exercise price per exercisable option	$ 68.09
Weighted-average remaining contractual term, exercisable options (in years)	6.2
Aggregate intrinsic value, exercisable options	$ 62.9
Assumptions the Company Used to Develop Fair Value Estimates
Weighted average expected life (in years)	3.1	3.0	3.2
Risk free interest rate	1.50%	1.10%	2.70%
Expected volatility	30.00%	20.00%	20.00%
Expected dividend yield	0.00%	0.00%	0.00%
Restricted Stock and Performance Shares [Member]
Summary of Nonvested Shares
Nonvested, beginning of period	0.5
Granted	0.2
Vested	(0.10)
Nonvested, end of period	0.6
Weighted-average grant date fair value, nonvested, beginning of period	$ 69.43
Weighted-average grant date fair value, granted	$ 70.60
Weighted-average grant date fair value, vested	$ 72.52
Weighted-average grant date fair value, nonvested, end of period	$ 68.26
Employee Stock Purchase Plan [Member]
Assumptions the Company Used to Develop Fair Value Estimates
Risk free interest rate	0.20%	0.20%	1.20%
Expected volatility	20.00%	20.00%	30.00%
Expected dividend yield	0.00%	0.00%	0.00%

COMMITMENTS AND CONTINGENT LIABILITIES (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Notes To Financial Statements [Abstract]
Judgment amount in connection with a patent infringement case	$ 7.8
Judgment amount in connection with a wrongful termination lawsuit	10.0
Length of agreement (agreement effective January 1, 2007) with United Healthcare Insurance Company to become its exclusive national laboratory provider	ten-year
Length of the period for which the Company is committed to reimburse United Healthcare for transition costs	three years
Maximum amount of reimbursable transition costs	200.0
Transition payments billed through the end of the reimbursement period	119.6
Transition costs paid to date	119.6
Letters of credit	37.4
Future minimum rental commitments [Abstract]
2011	148.4
2012	112.1
2013	73.6
2014	50.6
2015	29.0
Thereafter	74.2
Total minimum lease payments	487.9
Less: amounts included in restructuring and acquisition related accruals	6.9
Less: non-cancelable sub-lease income	0.2
Total minimum operating lease payments	480.8
Rental expense	202.1	182.9	175.1
Equipment lease guarantee	$ 1.6
Joint venture ownership interest (in hundredths)	50.00%
Remaining term on guaranteed equipment leases	two years

PENSION AND POSTRETIREMENT PLANS (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2008	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Notes To Financial Statements [Abstract]
Defined contribution retirement plan cost		$ 40.6	$ 15.2	$ 15.5
Company contributions to the defined benefit retirement plan		0	54.8	0
Minimum non-elective contribution (NEC) % for the 401(K) plan (in hundredths)		0.03
Discretionary contribution % for the 401(K) plan, range minimum (in hundredths)		0.01
Discretionary contribution % for the 401(K) plan, range maximum (in hundredths)		0.03
Projected defined benefit plan costs in fiscal 2011		8.9
Defined Benefit Plans Disclosures [Line Items]
Executive retirement charge	1.7			1.7
Defined Benefit Plans, Changes in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year		259.3
Fair value of plan assets at end of year		264.4	259.3
Defined Benefit Plans [Member]
Defined Benefit Plans Disclosures [Line Items]
Service cost for benefits earned		2.6	20.8	20.0
Interest cost on benefit obligation		18.1	18.3	17.2
Expected return on plan assets		(18.5)	(17.3)	(22.2)
Net amortization and deferral		7.4	12.0	2.8
Curtailment cost		0	2.8	0
Executive retirement charge		0	0	1.7
Defined benefit plan costs		9.6	36.6	19.5
Unamortized net loss (gain) included in accumulated other comprehensive earnings		109.3
Amortization of net loss (gain) in accumulated other comprehensive earnings, which is expected to be recognized as components of defined benefit plan costs during 2011		7.8
Defined Benefit Plans, Changes in Benefit Obligations [Roll Forward]
Beginning balance		328.0	292.7
Service cost		2.6	20.8	20.0
Interest cost		18.1	18.3	17.2
Actuarial loss (gain)		24.8	24.1
Amendments		0	0.9
Benefits and administrative expenses paid		(25.3)	(24.1)
Plan curtailment		0	(4.7)
Ending balance	292.7	348.2	328.0	292.7
Accumulated benefit obligation		348.2	328.0
Defined Benefit Plans, Changes in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year		259.3	170.1
Actual return on plan assets		29.3	57.4
Employer contributions		1.1	55.9
Fair value of plan assets at end of year	170.1	264.4	259.3	170.1
Defined Benefit Plans, Weighted Average Assumptions Used in Calculating Benefit Obligations [Abstract]
Discount rate (in hundredths)	6.50%	5.10%	5.80%	6.50%
Compensation increases (in hundredths)	3.50%	0.00%	0.00%	3.50%
Expected long term rate of return (in hundredths)	8.50%	7.50%	7.50%	8.50%
Defined Benefit Plans, Assets, Target Allocations [Abstract]
Target allocation for equity securities in plan assets (in hundredths)		55.00%
Target allocation for fixed income securities in plan assets (in hundredths)		40.00%
Target allocation for other assets in plan assets (in hundredths)		5.00%
Weighted average expected long-term rate of return for equity securities (in hundredths)		5.00%
Weighted average expected long-term rate of return for fixed income securities (in hundredths)		2.00%
Weighted average expected long-term rate of return for other assets (in hundredths)		0.50%
Post-Retirement Medical Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Service cost for benefits earned		0.3	0.3	0.4
Interest cost on benefit obligation		2.3	2.3	2.7
Net amortization and deferral		(0.9)	(1.7)	(1.7)
Defined benefit plan costs		1.7	0.9	1.4
Unamortized net loss (gain) included in accumulated other comprehensive earnings		(4.3)
Amortization of net loss (gain) in accumulated other comprehensive earnings, which is expected to be recognized as components of defined benefit plan costs during 2011		(0.1)
Defined Benefit Plans, Changes in Benefit Obligations [Roll Forward]
Beginning balance		39.6	36.7
Service cost		0.3	0.3	0.4
Interest cost		2.3	2.3	2.7
Participants contributions		0.4	0.4
Actuarial loss (gain)		0.8	1.4
Benefits and administrative expenses paid		(1.4)	(1.5)
Ending balance	$ 36.7	$ 42.0	$ 39.6	$ 36.7
Defined Benefit Plans, Weighted Average Assumptions Used in Calculating Benefit Obligations [Abstract]
Discount rate (in hundredths)		5.40%	6.00%
Health care cost trend rate (in hundredths)		7.50%	8.00%
Ultimate health care cost trend rate (in hundredths)		5.00%
Year in which the rate reaches the ultimate trend rate		2016

DEFINED BENEFIT PLANS, FAIR VALUE OF PLAN ASSETS (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2010	Dec. 31, 2009
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	$ 264.4	$ 259.3
Cash [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	2.3	13.8
U.S. large cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	62.7	80.5
U.S. mid cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	26.7
U.S. small cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	9.8	23.3
International - developed [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	37.5	32.5
International - emerging [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	8.2	7.1
Commodities index [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	15.0
U.S. fixed income [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	102.2	102.1
Level 1 [Member] \| Cash [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	2.3	13.8
Level 1 [Member] \| U.S. large cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 1 [Member] \| U.S. mid cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0
Level 1 [Member] \| U.S. small cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 1 [Member] \| International - developed [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 1 [Member] \| International - emerging [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 1 [Member] \| Commodities index [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0
Level 1 [Member] \| U.S. fixed income [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 2 [Member] \| Cash [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 2 [Member] \| U.S. large cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	62.7	80.5
Level 2 [Member] \| U.S. mid cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	26.7
Level 2 [Member] \| U.S. small cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	9.8	23.3
Level 2 [Member] \| International - developed [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	37.5	32.5
Level 2 [Member] \| International - emerging [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	8.2	7.1
Level 2 [Member] \| Commodities index [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	15.0
Level 2 [Member] \| U.S. fixed income [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	102.2	102.1
Level 3 [Member] \| Cash [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 3 [Member] \| U.S. large cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 3 [Member] \| U.S. small cap - blend [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 3 [Member] \| International - developed [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 3 [Member] \| International - emerging [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	0	0
Level 3 [Member] \| U.S. fixed income [Member]
Defined Benefit Plans, Fair Value of Plan Assets by Category [Line Items]
Defined Benefit Plans, Assets for Plan Benefits	$ 0	$ 0

PENSION AND POSTRETIREMENT PLANS, OTHER DISCLOSURES (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
Impact of a percentage point increase each year in the assumed health care cost trend rate on the accumulated post-retirement benefit obligation	$ 5.9
Impact of a percentage point decrease each year in the assumed health care cost trend rate on the accumulated post-retirement benefit obligation	(4.9)
Impact of a percentage point increase each year in the assumed health care cost trend rate on the service and interest cost components	0.4
Impact of a percentage point decrease each year in the assumed health care cost trend rate on the service and interest cost components	(0.3)
Defined Benefit Plans [Member]
Defined Benefit Plans, Estimated Future Benefit Payments [Abstract]
Benefit payments expected in 2011	23.2
Benefit payments expected in 2012	22.6
Benefit payments expected in 2013	22.9
Benefit payments expected in 2014	22.7
Benefit payments expected in 2015	23.3
Benefit payments expected in 2016-2020	119.7
Post-Retirement Medical Plan [Member]
Defined Benefit Plans, Estimated Future Benefit Payments [Abstract]
Benefit payments expected in 2011	1.7
Benefit payments expected in 2012	1.7
Benefit payments expected in 2013	1.8
Benefit payments expected in 2014	1.9
Benefit payments expected in 2015	2.1
Benefit payments expected in 2016-2020	$ 12.3

FAIR VALUE MEASUREMENTS (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2010	Dec. 31, 2009
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	$ 168.7	$ 142.4
Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	0	0
Interest rate swap liability	2.4	10.6
Total fair value of derivatives	2.4	10.6
Fair market value of zero-coupon subordinated notes	419.5	374.6
Fair market value of senior notes	1,549.8	645.2
Fair market value of variable rate debt	370.1	486.4
Level 1 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	0	0
Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	0	0
Interest rate swap liability	0	0
Total fair value of derivatives	0	0
Level 2 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	168.7	142.4
Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	0	0
Interest rate swap liability	2.4	10.6
Total fair value of derivatives	2.4	10.6
Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	0	0
Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	0	0
Interest rate swap liability	0	0
Total fair value of derivatives	$ 0	$ 0

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009
Notes To Financial Statements [Abstract]
Remaining term on interest rate swap agreement to hedge variable interest rate risk	two years
Fixed interest rate related to interest rate swap agreement	2.92%
Variable interest rate related to interest rate swap agreement	three-month LIBOR
Fair value of interest rate swap	$ 2.4	$ 10.6
Minimum percentage of market price to calculated value of zero-coupon subordinated debt at which the entity is subject to contingent cash interest	120.00%
Interest rate contract [Member]
Derivative Instruments, Gain (Loss)
Effective portion of derivative gain	8.2	2.9
Balance Sheet Location, Other Liabilities [Member]
Derivative Instruments in Statement of Financial Position at Fair Value
Other liabilities	$ 2.4	$ 10.6

EXECUTIVE RETIREMENT (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2008	Dec. 31, 2008
Notes To Financial Statements [Abstract]
Accelerated recognition of stock compensation and certain defined benefit plan obligations related to a certain individual, description		In October 2008, the Company announced the retirement of its Executive Vice President, Corporate Affairs (“EVP”), Bradford T. Smith, effective December 31, 2008. During the fourth quarter of 2008, the Company recorded charges of approximately $3.7, which included $2.0 related to the acceleration of the recognition of stock compensation and $1.7 related to the acceleration of certain defined benefit plan obligations. Following the announcement of his retirement as EVP, Mr. Smith entered into a consulting agreement with the Company effective January 1, 2009. The agreement provided for additional services to be provided by Mr. Smith following the termination of his employment as EVP to assist the Company during a transition period. Mr. Smith was Vice Chairman of the Board through the annual meeting of shareholders in May 2009. For purposes of calculating pension benefits, the agreement provided for an unreduced pension benefit, starting at age 55.
Executive retirement charges	$ 3.7
Acceleration of the recognition of stock compensation	2.0
Acceleration of certain defined benefit plan obligations	$ 1.7	$ 1.7
Agreement age at which the retired executive is eligible for unreduced pension benefits (in years)	55

SUPPLEMENTAL CASH FLOW INFORMATION (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Cash paid during period for:
Interest	$ 55.5	$ 50.7	$ 56.1
Income taxes, net of refunds	355.0	304.1	211.8
Disclosure of non-cash financing and investing activities
Surrender of restricted stock awards and performance shares	2.4	2.7	32.7
Accrued repurchases of common stock	(0.5)	0.5	(3.0)
Purchase of equipment in accrued expenses	$ 0	$ 2.8	$ 0

QUARTERLY DATA (UNAUDITED) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2009	Jun. 30, 2009	Mar. 31, 2009	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Summary of unaudited quarterly data
Net sales	$ 1,295.4	$ 1,276.5	$ 1,238.4	$ 1,193.6	$ 1,165.1	$ 1,185.1	$ 1,188.8	$ 1,155.7	$ 5,003.9	$ 4,694.7	$ 4,505.2
Gross profit	529.6	527.7	533.6	506.9	476.0	498.1	507.4	489.4	2,097.8	1,970.9	1,873.8
Net earnings attributable to Laboratory Corporation of America Holdings	$ 131.8	$ 140.0	$ 153.7	$ 132.7	$ 142.7	$ 131.4	$ 136.4	$ 132.8	$ 558.2	$ 543.3	$ 464.5
Earnings Per Share
Basic earnings per common share (in dollars per share)	$ 1.29	$ 1.37	$ 1.48	$ 1.27	$ 1.35	$ 1.22	$ 1.26	$ 1.23	$ 5.42	$ 5.06	$ 4.23
Diluted earnings per common share (in dollars per share)	$ 1.26	$ 1.34	$ 1.46	$ 1.25	$ 1.33	$ 1.21	$ 1.24	$ 1.22	$ 5.29	$ 4.98	$ 4.16

- Definition

The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

+ References+ Details

Schedule II - Valuation And Qualifying Accounts And Reserves (Details) (USD $)
In Millions, unless otherwise specified

12 Months Ended

Dec. 31, 2010

Dec. 31, 2009

Dec. 31, 2008

Allowance for doubtful accounts [Member]

Movement in Valuation Allowances and Reserves [Roll Forward]

Balance at beginning of year

$ 173.1

$ 161.0

$ 92.5

Charged to Costs and Expense

241.5

248.9

283.3

Additions as a Result of Acquisitions

4.8

5.9

Other (Deductions) Additions

(265.4)

^[1]

(241.6)

^[1]

(220.7)

^[1]

Balance at end of year

149.2

173.1

161.0

Valuation allowance-deferred tax assets [Member]

Movement in Valuation Allowances and Reserves [Roll Forward]

Balance at beginning of year

3.9

Charged to Costs and Expense

7.7

Additions as a Result of Acquisitions

Other (Deductions) Additions

(0.2)

^[1]

Balance at end of year

$ 11.4

$ 3.9

[1]	Other (Deductions) Additions consists primarily of write-offs of accounts receivable amounts.

Document Information	12 Months Ended
Document Information	Dec. 31, 2010
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2010

Entity Information (USD $) In Billions, except Share data in Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Feb. 18, 2011	Jun. 30, 2010
Entity Registrant Name	LABORATORY CORP OF AMERICA HOLDINGS
Entity Central Index Key	0000920148
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 7.8
Entity Common Stock, Shares Outstanding		100.0
Document Fiscal Year Focus	2010
Document Fiscal Period Focus	FY