0000920148-24-000032 | 10-Q | XBRL Viewer | Laboratory Corp OF America Holdings

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parentheticals) - USD ($) shares in Millions, $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Accounts Receivable, Allowance for Credit Loss	$ 34.2	$ 32.7
Shareholders' Equity:
Common stock, shares outstanding (in shares)	84.3	83.9

BUSINESS ACQUISITIONS	3 Months Ended
BUSINESS ACQUISITIONS	Mar. 31, 2024
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	BUSINESS ACQUISITIONS AND DISPOSITIONS During the three months ended March 31, 2024, the Company acquired several businesses and related assets for cash of approximately $259.2. These acquisitions consisted of the clinical and outreach businesses of Baystate Medical Center ($116.6), Providence Medical Foundation ($54.9), and Westpac Labs, Inc. ($87.7). The preliminary purchase considerations for these acquisitions were allocated under the acquisition method of accounting to the estimated fair market value of the net assets acquired, including approximately $159.4 in identifiable intangible assets. A residual amount of tax deductible goodwill of approximately $141.7 was recorded as of March 31, 2024. The amortization period for non-compete agreements and customer list assets acquired from these businesses are 5 and 15 years, respectively. The purchase price allocations for these acquisitions have not been finalized as of March 31, 2024. The preliminary valuation of acquired assets and assumed liabilities, include the following:

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2024
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	During the three months ended March 31, 2024, no director or officer of the Company adopted or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K. The Reorganization On April 25, 2024, the Company announced that it intends to implement a new holding company structure on May 17, 2024. The name of the new holding company will be Labcorp Holdings Inc. Labcorp Holdings Inc. will replace Laboratory Corporation of America Holdings as the publicly-traded entity and Laboratory Corporation of America Holdings will become a wholly owned subsidiary of Labcorp Holdings Inc. The name “Labcorp Holdings Inc.” is more closely aligned with our brand name, and the company will have a structure that is optimized to reflect our operations. Common stock will continue to trade on the NYSE on an uninterrupted basis under the existing symbol “LH” and Laboratory Corporation of America Holdings stockholders will automatically become stockholders of Labcorp Holdings Inc. on a one-for-one basis with all of the same rights.

EARNINGS PER SHARE (Reconciliation of Basic Earnings Per Share to Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Shares [Abstract]
Net earnings, basic (in shares)	84.1	88.4
Dilutive effect of employee stock options and awards, (in shares)	0.6	0.6
Income (Loss) from Continuing Operations, Per Diluted Share	$ 2.69	$ 2.34
Per Share Amount [Abstract]
Net Income (Loss) Available to Common Stockholders, Diluted	$ 228.0	$ 212.9
Weighted Average Number of Shares Outstanding, Diluted	84.7	89.0
Income (Loss) from Continuing Operations, Per Basic Share	$ 2.71	$ 2.35
Basic earnings per common share (in dollars per share)	2.71	2.41
Diluted earnings per common share (in dollars per share)	$ 2.69	$ 2.39

DEBT (Long-term debt) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
4.00% senior notes due 2023	$ 400.0	$ 400.0
3.60% senior notes due 2025	0.0	1,000.0
1.55% senior notes due 2026	500.0	500.0
3.60% senior notes due 2027	600.0	600.0
2.95% senior notes due 2029	650.0	650.0
4.70% senior notes due 2045	900.0	900.0
Long term debt issuance costs	24.4	26.3
Notes Payable, Noncurrent	0.6	0.6
Long-term Debt, Excluding Current Maturities	3,047.6	$ 4,054.7
Senior notes due 2027 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 600.0

GOODWILL AND INTANGIBLE ASSETS (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	$ 5,149.2		$ 5,058.4
Goodwill	6,218.9		6,142.5
Amortization of intangibles and other assets	60.1	$ 53.4
Adjustments to goodwill	(65.3)
Estimated amortization expense, 2013	237.3
Estimated amortization expense, 2014	228.4
Estimated amortization expense, 2015	217.1
Estimated amortization expense, 2016	209.0
Estimated amortization expense, Thereafter	1,737.4
Current Expected Credit Losses Opening Balance Sheet Impact on Retained Earnings	2.4
Amortization of intangible assets	60.1	$ 53.4
LabCorp Diagnostics [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	4,946.2		4,813.9
Adjustments to goodwill	(9.4)
Covance Drug Development [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	1,272.7		$ 1,328.6
Adjustments to goodwill	$ (55.9)

FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Millions	3 Months Ended
FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	$ 15.2	$ 15.5
Foreign Currency Contracts, Liability, Fair Value Disclosure	92.0
Fair market value of senior notes	4,829.2	4,850.4
Cash Surrender Value, Fair Value Disclosure	94.1	95.4
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	121.0	107.4
Contingent Consideration Classified as Equity, Fair Value Disclosure	79.8	66.1
Foreign Currency Contract, Asset, Fair Value Disclosure		109.0
Fair Value Hedges, Net	78.6	69.6
Tax effect of adjustments	0.0
Long-term Debt, Excluding Current Maturities	3,047.6	4,054.7
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	13.7
Senior notes due 2027 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Long-term Debt, Excluding Current Maturities	600.0
Senior notes due 2022 [Member] \| 2018 Swap Agreements
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Derivative, Notional Amount	300.0
Senior notes due 2024 \| 2022 Swap Agreements
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Derivative, Notional Amount	300.0
Level 1 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	0.0	0.0
Cash Surrender Value, Fair Value Disclosure	0.0	0.0
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	0.0	0.0
Contingent Consideration Classified as Equity, Fair Value Disclosure	0.0	0.0
Foreign Currency Contract, Asset, Fair Value Disclosure	0.0	0.0
Fair Value Hedges, Net	0.0	0.0
Deferred Compensation Plan Assets	0.0	0.0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	15.2	15.5
Foreign Currency Contracts, Liability, Fair Value Disclosure	92.0
Cash Surrender Value, Fair Value Disclosure	94.1	95.4
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	121.0	107.4
Contingent Consideration Classified as Equity, Fair Value Disclosure	0.0	0.0
Foreign Currency Contract, Asset, Fair Value Disclosure		109.0
Fair Value Hedges, Net	78.6	69.6
Deferred Compensation Plan Assets	28.3	21.1
Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	0.0	0.0
Cash Surrender Value, Fair Value Disclosure	0.0	0.0
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	0.0	0.0
Contingent Consideration Classified as Equity, Fair Value Disclosure	79.8	66.1
Foreign Currency Contract, Asset, Fair Value Disclosure	0.0	0.0
Fair Value Hedges, Net	0.0	0.0
Deferred Compensation Plan Assets	$ 0.0	$ 0.0

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss) Attributable to Parent	$ 228.0	$ 212.9

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net restructuring and other special charges	$ 5.0	$ 7.5
Operating Income (Loss)	321.3	329.8
Interest Expense	46.9	50.7
Equity method income, net	0.1	(2.1)
Investment income	2.9	2.2
Other, net	20.0	(6.9)
Earnings before income taxes	297.4	272.3
Provision for income taxes	69.1	63.9
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	228.3	208.4
Net earnings	228.3	213.3
Net Income (Loss) Attributable to Noncontrolling Interest	0.3	0.4
Net Income (Loss) Attributable to Parent	$ 228.0	$ 212.9
Income (Loss) from Continuing Operations, Per Basic Share	$ 2.71	$ 2.35
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	0	0.06
Basic earnings per common share (in dollars per share)	2.71	2.41
Diluted earnings per common share (in dollars per share)	$ 2.69	$ 2.39
Revenues	$ 3,176.6	$ 3,037.8
Cost of Revenue	2,279.3	2,187.7
Gross Profit	897.3	850.1
Selling, general and administrative expenses	508.4	457.2
Amortization of intangibles and other assets	60.1	53.4
Asset Impairment Charges	2.5	2.2
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 0.0	$ 4.9
Income (Loss) from Continuing Operations, Per Diluted Share	$ 2.69	$ 2.34
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share	$ 0	$ 0.05
Revenues	$ 3,176.6	$ 3,037.8
Cost of Revenue	2,279.3	2,187.7
Gross Profit	897.3	850.1
Selling, general and administrative expenses	508.4	457.2
Amortization of intangibles and other assets	60.1	53.4
Asset Impairment Charges	2.5	2.2
Net restructuring and other special charges	5.0	7.5
Operating Income (Loss)	321.3	329.8
Earnings before income taxes	297.4	272.3
Provision for income taxes	69.1	63.9
Net earnings	228.3	213.3
Less: Net earnings attributable to the noncontrolling interest	(0.3)	(0.4)
Net earnings attributable to Laboratory Corporation of America Holdings	$ 228.0	$ 212.9
Basic earnings per common share (in dollars per share)	$ 2.71	$ 2.41
Diluted earnings per common share (in dollars per share)	$ 2.69	$ 2.39

SUPPLEMENTAL CASH FLOW INFORMATION Description Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash paid during period for:
Interest	$ 71.6	$ 70.5
Income taxes, net of refunds	21.5	28.4
Disclosure of non-cash financing and investing activities:
Decrease in Capital Expenditures Incurred but not yet Paid	$ (12.2)	$ (3.9)

BUSINESS SEGMENT INFORMATION Business Segment information (Notes)

3 Months Ended

Mar. 31, 2024

Segment Reporting Information [Line Items]

Segment Reporting Disclosure [Text Block]

BUSINESS SEGMENT INFORMATION

The following table is a summary of segment information for the three months ended March 31, 2024, and 2023. The “management approach” has been used to present the following segment information. This approach is based upon the way the management of the Company organizes segments within an enterprise for making operating decisions and assessing performance. Financial information is reported on the basis that it is used internally by the chief operating decision maker (CODM) for evaluating segment performance and deciding how to allocate resources to segments. The Company’s chief executive officer has been identified as the CODM.

The prior period has been conformed to the new segment presentation as a result of the spin-off of Fortrea.

Segment asset information is not presented because it is not used by the CODM at the segment level. The Corporate costs not allocated to segments include the costs of centralized functions, other charges such as acquisition expenses, spin-off costs, remaining unallocated costs of the CDCS business, and COVID-19 related costs unrelated to the segment. Centralized functions include corporate governance, executive management and related human resources, finance, legal, risk management, and information technology functions.


	Three Months Ended March 31,
		2024		2023
Revenues:
Dx		$	2,479.7	$	2,382.8
BLS		710.9		661.3
Intercompany eliminations and other		(14.0)		(6.3)
Total revenues		$	3,176.6	$	3,037.8

Operating Earnings:
Dx segment operating income		$	417.9	$	441.5
BLS segment operating income		99.9		73.6
Segment operating income		517.8		515.1
General corporate and unallocated expenses		(128.9)		(122.2)
Amortization of intangibles and other assets		(60.1)		(53.4)
Restructuring and other charges		(5.0)		(7.5)
Goodwill and other asset impairments		(2.5)		(2.2)

Total operating income		$	321.3	$	329.8

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-15

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-40

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//280/tableOfContent

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-26

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-34

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-41

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

+ Details

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY (Details) - USD ($)		3 Months Ended
	Apr. 11, 2024	Mar. 31, 2024	Mar. 31, 2023
Class of Stock [Line Items]
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased		531,500,000
Common Shares Outstanding Rollforward [Abstract]
Common shares outstanding, beginning balance (in shares)		83,900,000
Common shares outstanding, ending balance (in shares)		84,300,000
Rollforward of common shares held in treasury
Common Stock, Shares Authorized		265,000,000.0
Common Stock, Par or Stated Value Per Share		$ 0.10
Preferred Stock, Shares Authorized		30,000,000.0
Preferred Stock, Par or Stated Value Per Share		$ 0.10
Preferred Stock, Shares Outstanding		0
Tax effect of adjustments		$ 0
Dividends		60,900,000	$ 64,700,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax		(900,000)
Foreign currency translation adjustments		(124,300,000)	48,100,000
Dividends		$ 60,900,000	$ 64,700,000
Subsequent Event [Member]
Rollforward of common shares held in treasury
Dividends Payable, Date of Record	May 28, 2024
Dividends Payable, Date Declared	Apr. 11, 2024
Dividends Payable, Amount Per Share	$ 0.72
Dividends	$ 61,400,000
Dividends Payable, Date to be Paid	Jun. 12, 2024
Dividends Payable, Date Declared	Apr. 11, 2024
Dividends Payable, Date to be Paid	Jun. 12, 2024
Dividends Payable, Date of Record	May 28, 2024
Dividends Payable, Amount Per Share	$ 0.72
Dividends	$ 61,400,000
Common Stock [Member]
Rollforward of common shares issued
Common shares issued, beginning balance (in shares)		83,900,000
Commons Stock Issued During Period Shares Employee Stock Plans		400,000
Common shares issued, ending balance (in shares)		84,300,000
Common Stock, Shares, Issued		84,300,000
Common Shares Outstanding Rollforward [Abstract]
Commons Stock Issued During Period Shares Employee Stock Plans		400,000
Commons Stock Issued During Period Shares Employee Stock Plans		400,000

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
CASH FLOWS FROM OPERATING ACTIVITIES:
Net earnings	$ 228.3	$ 213.3
Earnings from discontinued operations, net of tax	0.0	(4.9)
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	154.5	142.1
Stock compensation	31.6	32.9
Operating lease right-of-use asset expense	44.1	40.5
Goodwill and other asset impairments	2.5	2.2
Deferred income taxes	(19.5)	27.2
Other	(3.0)	9.6
Change in assets and liabilities (net of effects of acquisitions and divestitures):
Increase (Decrease) in Accounts Receivable	(187.1)	(108.4)
Increase (Decrease) in Unbilled Contract Receivable	63.9	56.9
Increase (Decrease) in Inventories	(0.6)	(10.0)
Increase in prepaid expenses and other	24.9	57.5
Increase (Decrease) in Accounts Payable	(121.1)	(77.7)
Increase (Decrease) in Deferred Revenue	(41.6)	16.3
Decrease in accrued expenses and other	(156.9)	(96.8)
Net Cash Provided by (Used in) Operating Activities, Total	(29.8)	121.2
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(133.8)	(78.2)
Proceeds from sale of assets	0.1	0.1
Proceeds from Sales of Business, Affiliate and Productive Assets	13.5	0.0
Investments in equity affiliates	(13.7)	(6.1)
Acquisition of businesses, net of cash acquired	(259.2)	0.2
Net cash used for investing activities	(393.1)	(99.7)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from revolving credit facilities	253.2	827.9
Payments on revolving credit facilities	(210.8)	(827.9)
Net share settlement tax payments from issuance of stock to employees	14.7	20.5
Net proceeds from issuance of stock to employees	26.7	27.6
Dividends paid	62.1	64.4
Other	4.0	3.3
Net cash used for financing activities	(11.7)	(60.6)
Effect of exchange rate changes on cash and cash equivalents	(2.9)	3.0
Net decrease in cash and cash equivalents	(437.5)	(36.1)
Cash and cash equivalents at beginning of period	536.8	430.0
Cash and cash equivalents at end of period	99.3	294.8
Discontinued Operations
Change in assets and liabilities (net of effects of acquisitions and divestitures):
Net cash used for discontinued operating activities	0.0	(64.5)
CASH FLOWS FROM INVESTING ACTIVITIES:
Net cash used for discontinued investing activities	0.0	(15.7)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net cash provided by discontinued financing activities	0.0	0.0
Continuing Operations
Change in assets and liabilities (net of effects of acquisitions and divestitures):
Net cash provided by (used for) continuing operating activities	(29.8)	185.7
CASH FLOWS FROM INVESTING ACTIVITIES:
Net cash used for continuing investing activities	(393.1)	(84.0)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net cash used for continuing financing activities	(11.7)	(60.6)
Less: Cash and cash equivalents of discontinued operations at end of period	$ 0.0	$ 99.1

Discontinued Operations and Disposal Groups (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Jun. 30, 2023
Discontinued Operations and Disposal Groups [Abstract]
Disposal Group, Including Discontinued Operation, Revenue		$ 740.1
Disposal Group, Including Discontinued Operation, Costs of Goods Sold		615.5
Disposal Group, Including Discontinued Operation, Gross Profit (Loss)		124.6
Disposal Group, Including Discontinued Operation, General and Administrative Expense		96.4
Disposal Group, Including Discontinued Operation, Depreciation and Amortization		15.9
Disposal Group, Including Discontinued Operation, Restructuring and other charges		1.1
Disposal Group, Including Discontinued Operation, Operating Income (Loss)		11.2
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax		5.5
Discontinued Operation, Tax Effect of Discontinued Operation		0.6
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 0.0	4.9
Disposal Group, Including Discontinued Operation, Fortrea Senior Notes			$ 570.0
Disposal Group, Including Discontinued Operation, Fortrea Senior Notes Interest Rate			7.50%
Disposal Group, Including Discontinued Operation, Fortrea Distribution	$ 1,600.0
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities			$ 1,520.0
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities			1,520.0
Disposal Group, Including Discontinued Operations, Other Nonoperating income (expense)		$ (5.7)
Fortrea Revolver due 2028
Discontinued Operations and Disposal Groups [Abstract]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities			450.0
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities			450.0
Fortrea Term Loan A maturing 2028
Discontinued Operations and Disposal Groups [Abstract]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities			500.0
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities			500.0
Fortrea Term Loan B maturing 2028
Discontinued Operations and Disposal Groups [Abstract]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities			570.0
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities			$ 570.0

EARNINGS PER SHARE (Tables)

3 Months Ended

Mar. 31, 2024

Earnings Per Share [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:


	Three Months Ended March 31,
		2024	2023
				Earnings		Shares	Per Share Amount		Earnings		Shares	Per Share Amount
Basic earnings per share:
Net earnings				$	228.0	84.1	$	2.71	$	212.9	88.4	$	2.41
Dilutive effect of employee stock options and awards				—		0.6			—		0.6


Net earnings including impact of dilutive adjustments				$	228.0	84.7	$	2.69	$	212.9	89.0	$	2.39

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:


	Three Months Ended March 31,
	2024	2023
Employee stock options and awards	0.3	0.6

GOODWILL AND INTANGIBLE ASSETS (Changes in Carrying Amount of Goodwill) (Details) - USD ($)
$ in Millions

3 Months Ended

Mar. 31, 2024

Mar. 31, 2023

Dec. 31, 2023

Goodwill [Line Items]

Amortization of intangibles and other assets

$ 60.1

$ 53.4

Intangible Assets, Gross (Excluding Goodwill)

5,149.2

$ 5,058.4

Balance as of January 1

6,142.5

Adjustments to goodwill

(65.3)

Balance at end of period

6,218.9

Finite-Lived Intangible Assets, Accumulated Amortization

1,755.1

1,716.4

Intangible Assets, Net (Excluding Goodwill)

3,394.1

3,342.0

Goodwill, Acquired During Period

$ 141.7

Goodwill [Roll Forward]

Goodwill and Intangible Assets, Goodwill, Policy

6. GOODWILL AND INTANGIBLE ASSETS

The changes in the carrying amount of goodwill for the three months ended March 31, 2024, were as follows:


	Dx		BLS		Total

Balance as of December 31, 2023	$	4,813.9	$	1,328.6	$	6,142.5
Goodwill acquired during the period	141.7		—		141.7



Foreign currency impact and other adjustments to goodwill	(9.4)		(55.9)		(65.3)
Balance as of March 31, 2024	$	4,946.2	$	1,272.7	$	6,218.9

The Company assesses goodwill and indefinite-lived intangibles for impairment at least annually or whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. The Company recognizes an impairment charge for the amount by which the reporting unit's carrying amount exceeds its fair value.

Although the Company believes that the current assumptions and estimates used in its goodwill analysis are reasonable, supportable, and appropriate, the Company's business could be impacted by unfavorable changes, including those that impact the existing assumptions used in the impairment analysis. Various factors could reasonably be expected to unfavorably impact existing assumptions: primarily, a worsening economic environment and protracted economic downturn and related impacts, including delays in revenue from new customers; increases in customer termination activity; or increases in operating costs. Accordingly, there can be no assurance that the estimates and assumptions made for the purposes of the goodwill impairment analysis will prove to be accurate predictions of future performance.

The Company will continue to monitor the financial performance of, and assumptions for, its reporting units. A significant increase in the discount rate, decrease in the revenue and terminal growth rates, decreased operating margin, or substantial reductions in end markets and volume assumptions, could have a negative impact on the estimated fair value of the reporting units. A future impairment charge for goodwill or intangible assets could have a material effect on the Company's consolidated financial position and results of operations.

The components of identifiable intangible assets were as follows:


	March 31, 2024						December 31, 2023
	Gross Carrying Amount		Accumulated Amortization		Net		Gross Carrying Amount		Accumulated Amortization		Net
Customer relationships	$	3,945.3	$	(1,395.7)	$	2,549.6	$	3,868.6	$	(1,367.2)	$	2,501.4
Patents, licenses and technology	521.4		(276.8)		244.6		526.6		(273.3)		253.3
Non-compete agreements	152.4		(65.9)		86.5		130.3		(60.4)		69.9
Trade name	16.4		(6.9)		9.5		16.4		(6.1)		10.3
Land use right	3.5		(2.8)		0.7		3.5		(2.7)		0.8
Canadian licenses	496.0		—		496.0		498.8		—		498.8
Other	14.2		(7.0)		7.2		14.2		(6.7)		7.5
	5,149.2		(1,755.1)		3,394.1		5,058.4		(1,716.4)		3,342.0

Amortization of intangible assets for the three months ended March 31, 2024, and 2023, was $60.1 and $53.4, respectively. The amortization expense for the net carrying amount of intangible assets is estimated to be $183.3 for the remainder of fiscal 2024, $237.3 in fiscal 2025, $228.4 in fiscal 2026, $217.1 in fiscal 2027, $209.0 in fiscal 2028, and $1,737.4 thereafter.

LabCorp Diagnostics [Member]

Goodwill [Line Items]

Balance as of January 1

$ 4,813.9

Adjustments to goodwill

(9.4)

Balance at end of period

4,946.2

Goodwill, Acquired During Period

141.7

Covance Drug Development [Member]

Goodwill [Line Items]

Balance as of January 1

1,328.6

Adjustments to goodwill

(55.9)

Balance at end of period

1,272.7

Goodwill, Acquired During Period

0.0

Customer Relationships [Member]

Goodwill [Line Items]

Intangible Assets, Gross (Excluding Goodwill)

3,945.3

3,868.6

Finite-Lived Intangible Assets, Accumulated Amortization

1,395.7

1,367.2

Intangible Assets, Net (Excluding Goodwill)

2,549.6

2,501.4

Patents, Licenses And Technology [Member]

Goodwill [Line Items]

Intangible Assets, Gross (Excluding Goodwill)

521.4

526.6

Finite-Lived Intangible Assets, Accumulated Amortization

276.8

273.3

Intangible Assets, Net (Excluding Goodwill)

244.6

253.3

Noncompete Agreements [Member]

Goodwill [Line Items]

Intangible Assets, Gross (Excluding Goodwill)

152.4

130.3

Finite-Lived Intangible Assets, Accumulated Amortization

65.9

60.4

Intangible Assets, Net (Excluding Goodwill)

86.5

69.9

Trade Names [Member]

Goodwill [Line Items]

Intangible Assets, Gross (Excluding Goodwill)

16.4

Finite-Lived Intangible Assets, Accumulated Amortization

6.9

6.1

Intangible Assets, Net (Excluding Goodwill)

9.5

10.3

Use Rights [Member]

Goodwill [Line Items]

Intangible Assets, Gross (Excluding Goodwill)

3.5

Finite-Lived Intangible Assets, Accumulated Amortization

2.8

2.7

Intangible Assets, Net (Excluding Goodwill)

0.7

0.8

Canadian licenses [Member]

Goodwill [Line Items]

Intangible Assets, Gross (Excluding Goodwill)

496.0

498.8

Finite-Lived Intangible Assets, Accumulated Amortization

0.0

Intangible Assets, Net (Excluding Goodwill)

$ 496.0

$ 498.8

Intangible Assets, Goodwill and Other (Policies)

3 Months Ended

Mar. 31, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets, Goodwill, Policy

6. GOODWILL AND INTANGIBLE ASSETS

The changes in the carrying amount of goodwill for the three months ended March 31, 2024, were as follows:


	Dx		BLS		Total

Balance as of December 31, 2023	$	4,813.9	$	1,328.6	$	6,142.5
Goodwill acquired during the period	141.7		—		141.7



Foreign currency impact and other adjustments to goodwill	(9.4)		(55.9)		(65.3)
Balance as of March 31, 2024	$	4,946.2	$	1,272.7	$	6,218.9

The components of identifiable intangible assets were as follows:


	March 31, 2024						December 31, 2023
	Gross Carrying Amount		Accumulated Amortization		Net		Gross Carrying Amount		Accumulated Amortization		Net
Customer relationships	$	3,945.3	$	(1,395.7)	$	2,549.6	$	3,868.6	$	(1,367.2)	$	2,501.4
Patents, licenses and technology	521.4		(276.8)		244.6		526.6		(273.3)		253.3
Non-compete agreements	152.4		(65.9)		86.5		130.3		(60.4)		69.9
Trade name	16.4		(6.9)		9.5		16.4		(6.1)		10.3
Land use right	3.5		(2.8)		0.7		3.5		(2.7)		0.8
Canadian licenses	496.0		—		496.0		498.8		—		498.8
Other	14.2		(7.0)		7.2		14.2		(6.7)		7.5
	5,149.2		(1,755.1)		3,394.1		5,058.4		(1,716.4)		3,342.0

EARNINGS PER SHARE

3 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Earnings Per Share

EARNINGS PER SHARE

Basic earnings per share is computed by dividing net earnings attributable to the Company by the weighted average number of shares of the Company's common stock 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, restricted stock units, and performance share awards.

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


	Three Months Ended March 31,
		2024	2023
				Earnings		Shares	Per Share Amount		Earnings		Shares	Per Share Amount
Basic earnings per share:
Net earnings				$	228.0	84.1	$	2.71	$	212.9	88.4	$	2.41
Dilutive effect of employee stock options and awards				—		0.6			—		0.6


Net earnings including impact of dilutive adjustments				$	228.0	84.7	$	2.69	$	212.9	89.0	$	2.39

Diluted earnings per share represent the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock. These potential shares include dilutive stock options and unissued restricted stock awards. 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:


	Three Months Ended March 31,
	2024	2023
Employee stock options and awards	0.3	0.6

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2024
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS On April 24, 2024, the Company announced that it has been selected as the winning bidder for select assets of Invitae, a leading medical genetics company. Before the transaction can proceed, the court overseeing the process must issue an approval order following a hearing currently scheduled for May 6, 2024. The purchase price for the transaction is $239.0. The transaction is anticipated to close in third quarter of 2024, subject to customary closing conditions for a transaction of this type, including applicable regulatory approvals. Through this transaction, the Company would acquire assets being auctioned through a voluntary bankruptcy protection process.

GOODWILL AND INTANGIBLE ASSETS (Tables)

3 Months Ended

Mar. 31, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

Changes in Carrying Amount of Goodwill

The changes in the carrying amount of goodwill for the three months ended March 31, 2024, were as follows:


	Dx		BLS		Total

Balance as of December 31, 2023	$	4,813.9	$	1,328.6	$	6,142.5
Goodwill acquired during the period	141.7		—		141.7



Foreign currency impact and other adjustments to goodwill	(9.4)		(55.9)		(65.3)
Balance as of March 31, 2024	$	4,946.2	$	1,272.7	$	6,218.9

Schedule of Intangible Assets and Goodwill [Table Text Block]

he components of identifiable intangible assets were as follows:


	March 31, 2024						December 31, 2023
	Gross Carrying Amount		Accumulated Amortization		Net		Gross Carrying Amount		Accumulated Amortization		Net
Customer relationships	$	3,945.3	$	(1,395.7)	$	2,549.6	$	3,868.6	$	(1,367.2)	$	2,501.4
Patents, licenses and technology	521.4		(276.8)		244.6		526.6		(273.3)		253.3
Non-compete agreements	152.4		(65.9)		86.5		130.3		(60.4)		69.9
Trade name	16.4		(6.9)		9.5		16.4		(6.1)		10.3
Land use right	3.5		(2.8)		0.7		3.5		(2.7)		0.8
Canadian licenses	496.0		—		496.0		498.8		—		498.8
Other	14.2		(7.0)		7.2		14.2		(6.7)		7.5
	5,149.2		(1,755.1)		3,394.1		5,058.4		(1,716.4)		3,342.0

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482548/350-20-55-24

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1A

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-2

+ Details

FAIR VALUE MEASUREMENTS

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements

FAIR VALUE MEASUREMENTS

The Company’s population of financial assets and liabilities subject to fair value measurements as of March 31, 2024, and December 31, 2023, was as follows:


				Fair Value Measurements as of
				March 31, 2024
	Balance Sheet	Fair Value as of		Using Fair Value Hierarchy
	Classification	March 31, 2024		Level 1		Level 2		Level 3
Noncontrolling interest put	Noncontrolling interest	$	15.2	$	—	$	15.2	$	—
Cross currency swaps	Other liabilities	92.0		—		92.0		—
Interest rate swaps	Other liabilities	78.6		—		78.6		—


Cash surrender value of life insurance policies	Other assets, net	94.1		—		94.1		—
Deferred compensation asset	Other assets, net	28.3		—		28.3		—
Deferred compensation liability	Other liabilities	121.0		—		121.0		—

Contingent consideration	Accrued expenses and other; Other liabilities	79.8		—		—		79.8


				Fair Value Measurements as of
				December 31, 2023
	Balance Sheet	Fair Value as of		Using Fair Value Hierarchy
	Classification	December 31, 2023		Level 1		Level 2		Level 3
Noncontrolling interest put	Noncontrolling interest	$	15.5	$	—	$	15.5	$	—
Cross currency swaps	Accrued expenses and other; Other liabilities	109.0		—		109.0		—
Interest rate swaps	Other liabilities, net	69.6		—		69.6		—
Cash surrender value of life insurance policies	Other assets, net	95.4		—		95.4		—
Deferred compensation asset	Other assets, net	21.1		—		21.1		—
Deferred compensation liability	Other liabilities	107.4		—		107.4		—

Contingent consideration	Accrued expenses and other; Other liabilities	66.1		—		—		66.1


Fair Value Measurement of Level 3 Liabilities	Contingent Consideration
Balance at December 31, 2023	$	66.1


Additions	13.7
Balance as of March 31, 2024	$	79.8

The Company has a noncontrolling interest put related to its Ontario subsidiary that has been classified as mezzanine equity in the Company’s condensed consolidated balance sheets. The noncontrolling interest put is valued at its contractually determined value, which approximates fair value.

The Company offers certain employees the opportunity to participate in an employee-funded deferred compensation plan (DCP). A participant's deferrals are allocated by the participant to one or more of multiple measurement funds, which are indexed to externally managed funds. From time to time, to offset the cost of the growth in the participant's investment accounts, the Company purchases life insurance policies, with the Company named as beneficiary of the policies. Changes in the cash surrender value of the life insurance policies are based upon earnings and changes in the value of the underlying

investments, which are typically invested in a similar manner to the participant's allocations. Changes in the fair value of the DCP obligation are derived using quoted prices in active markets based on the market price per unit multiplied by the number of units. The cash surrender value and the DCP obligations are classified within Level 2 because their inputs are derived principally from observable market data by correlation to the hypothetical investments.

Contingent accrued earn-out business acquisition consideration liabilities are measured at fair value using Level 3 valuations. These contingent consideration liabilities were recorded at fair value on the acquisition date and are remeasured quarterly based on the then assessed fair value and adjusted if necessary. The increases or decreases in the fair value of contingent consideration payable can result from changes in anticipated revenue levels and changes in assumed discount periods and rates. As the fair value measure is based on significant inputs that are not observable in the market, they are categorized as Level 3.

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 senior notes, based on market pricing, was approximately $4,829.2 and $4,850.4 as of March 31, 2024, and December 31, 2023, respectively. The Company's note and debt instruments are classified as Level 2 instruments, as the fair market values of these instruments are determined using other observable inputs.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial 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 entity 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 risks 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

REVENUE (Details) - USD ($) $ in Millions	3 Months Ended
REVENUE (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Revenue from Contract with Customer [Abstract]
Deferred Revenue, Revenue Recognized	$ 51.0	$ 52.6

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY - Accumulated Other Comprehensive Earnings (Details) - USD ($)

3 Months Ended

Mar. 31, 2024

Mar. 31, 2023

Accumulated Other Comprehensive Income (Loss) [Line Items]

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

The components of accumulated other comprehensive earnings (loss) were as follows:


	Foreign Currency Translation Adjustments		Net Benefit Plan Adjustments		Accumulated Other Comprehensive Earnings (Loss)
Balance as of December 31, 2023	$	(47.6)	$	(11.7)	$	(59.3)

Current year adjustments	(124.3)		(1.5)		(125.8)

Amounts reclassified from accumulated other comprehensive income	—		(0.9)		(0.9)
Tax effect of adjustments	—		0.6		0.6
Balance as of March 31, 2024	$	(171.9)	$	(13.5)	$	(185.4)

Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax

$ (1,500,000)

Other Comprehensive Income (Loss), before Reclassifications, before Tax

(125,800,000)

Accumulated Other Comprehensive Earnings [Roll Forward]

Foreign Currency Translation Adjustments, Beginning balance

(47,600,000)

Other comprehensive income before reclassifications

(124,300,000)

Tax effect of adjustments

Foreign Currency Translation Adjustments, Ending balance

(171,900,000)

Net Benefit Plan Adjustments, Beginning balance

(11,700,000)

Tax effect of adjustments

600,000

Net Benefit Plan Adjustments, Ending balance

(13,500,000)

Accumulated Other Comprehensive Earnings, Beginning balance

(59,300,000)

Other comprehensive income before reclassifications

(124,300,000)

Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax

Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax

(900,000)

Tax effect of adjustments

600,000

$ (300,000)

Accumulated Other Comprehensive Earnings, Ending balance

$ (185,400,000)

Subsequent Events (Details) - Subsequent Event [Member]	1 Months Ended
Subsequent Events (Details) - Subsequent Event [Member]	Apr. 29, 2024
Subsequent Events [Abstract]
Subsequent Event [Member]	239.0
Subsequent Event [Line Items]
Subsequent Event [Member]	239.0

EARNINGS PER SHARE (Potential common shares not included in computation of diluted earnings per share) (Details) - shares shares in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Stock options (in shares)	0.3	0.6

FAIR VALUE MEASUREMENTS (Tables)

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Company's 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 March 31, 2024, and December 31, 2023, was as follows:


				Fair Value Measurements as of
				March 31, 2024
	Balance Sheet	Fair Value as of		Using Fair Value Hierarchy
	Classification	March 31, 2024		Level 1		Level 2		Level 3
Noncontrolling interest put	Noncontrolling interest	$	15.2	$	—	$	15.2	$	—
Cross currency swaps	Other liabilities	92.0		—		92.0		—
Interest rate swaps	Other liabilities	78.6		—		78.6		—


Cash surrender value of life insurance policies	Other assets, net	94.1		—		94.1		—
Deferred compensation asset	Other assets, net	28.3		—		28.3		—
Deferred compensation liability	Other liabilities	121.0		—		121.0		—

Contingent consideration	Accrued expenses and other; Other liabilities	79.8		—		—		79.8


				Fair Value Measurements as of
				December 31, 2023
	Balance Sheet	Fair Value as of		Using Fair Value Hierarchy
	Classification	December 31, 2023		Level 1		Level 2		Level 3
Noncontrolling interest put	Noncontrolling interest	$	15.5	$	—	$	15.5	$	—
Cross currency swaps	Accrued expenses and other; Other liabilities	109.0		—		109.0		—
Interest rate swaps	Other liabilities, net	69.6		—		69.6		—
Cash surrender value of life insurance policies	Other assets, net	95.4		—		95.4		—
Deferred compensation asset	Other assets, net	21.1		—		21.1		—
Deferred compensation liability	Other liabilities	107.4		—		107.4		—

Contingent consideration	Accrued expenses and other; Other liabilities	66.1		—		—		66.1

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]


Fair Value Measurement of Level 3 Liabilities	Contingent Consideration
Balance at December 31, 2023	$	66.1


Additions	13.7
Balance as of March 31, 2024	$	79.8

Revenue from Contract with Customer (Policies)

3 Months Ended

Mar. 31, 2024

Revenue from Contract with Customer [Abstract]

Revenue

REVENUES

The Company's revenues by segment and by payers/customer groups for the three months ended March 31, 2024, and 2023, were as follows:


	For the Three Months Ended March 31, 2024								For the Three Months Ended March 31, 2023
	North America		Europe		Other		Total		North America		Europe		Other		Total
Payer/Customer
Dx
Clients	25	%	—	%	—	%	25	%	25	%	—	%	—	%	25	%
Patients	10	%	—	%	—	%	10	%	9	%	—	%	—	%	9	%
Medicare and Medicaid	8	%	—	%	—	%	8	%	8	%	—	%	—	%	8	%
Third party	35	%	—	%	—	%	35	%	36	%	—	%	—	%	36	%
Total Dx revenues by payer	78	%	—	%	—	%	78	%	78	%	—	%	—	%	78	%
BLS




Pharmaceutical, biotechnology and medical device companies	9	%	9	%	4	%	22	%	9	%	9	%	4	%	22	%
Total revenues	87	%	9	%	4	%	100	%	87	%	9	%	4	%	100	%

Revenues in the U.S. were $2,654.6 (83.6%) and $2,557.4 (84.2%) for the three months ended March 31, 2024, and 2023, respectively.

Accounts Receivable, Unbilled Services and Unearned Revenue

The following table provides information about accounts receivable, unbilled services, and unearned revenue from contracts with customers:


	March 31, 2024		December 31, 2023
Dx accounts receivable	$	1,260.9	$	1,135.2
BLS accounts receivable	857.0		810.8
Less BLS allowance for doubtful accounts	(34.2)		(32.7)
Accounts receivable	$	2,083.7	$	1,913.3

Gross unbilled services	$	127.8	$	192.9
Less reserve for unbilled services	(7.4)		(7.5)
Unbilled services	$	120.4	$	185.4

Unearned revenue	$	377.5	$	421.7

Revenues recognized during the period that were included in the unearned revenue balance at the beginning of the period were $51.0 and $52.6 for the three months ended March 31, 2024 and 2023, respectively.

Credit Loss Rollforward

The Company estimates future expected losses on accounts receivable, unbilled services and notes receivable over the remaining collection period of the instrument. The rollforward for the allowance for credit losses for the three months ended March 31, 2024, was as follows:


	Accounts Receivable		Unbilled Services		Note and Other Receivables		Total
Balance as of December 31, 2023	$	32.7	$	7.5	$	0.7	$	40.9
Plus, credit loss expense	2.4		—		—		2.4

Less, write offs	0.9		0.1		—		1.0
Balance as of March 31, 2024	$	34.2	$	7.4	$	0.7	$	42.3

The credit loss expense in the first three months primarily related to the collection risk from several biotech receivable balances in the first quarter.

SUPPLEMENTAL CASH FLOW INFORMATION

3 Months Ended

Mar. 31, 2024

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

SUPPLEMENTAL CASH FLOW INFORMATION


	Three Months Ended March 31,
	2024		2023

Cash paid during period for:
Interest	$	71.6	$	70.5
Income taxes, net of refunds	21.5		28.4
Disclosure of non-cash financing and investing activities:



Change in accrued property, plant, and equipment	(12.2)		(3.9)

BUSINESS ACQUISITIONS (Details) - USD ($) $ in Millions	3 Months Ended
BUSINESS ACQUISITIONS (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Business Combinations [Abstract]
Payments to Acquire Businesses, Net of Cash Acquired	$ 259.2	$ (0.2)
Business Acquisition [Line Items]
Goodwill, Acquired During Period	141.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	0.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(311.0)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(21.8)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	289.2	0.0
Business Acquisition, Pro Forma Revenue	3,191.1	3,106.0
Business Acquisition, Pro Forma Net Income (Loss)	227.5	216.2
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	8.1
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	1.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	(159.4)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	0.0
Payments to Acquire Businesses, Net of Cash Acquired	259.2	(0.2)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	13.7
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	259.2
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory	0.0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment	0.0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments Related to Previous Period	0.0
Escrow Deposit	30.0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	7.4
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Assets	0.0	(10.4)
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation	8.1
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities	0.0	(10.4)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	0.0	0.2
Estimated amortization expense, 2012	183.3
Accrued Liabilities [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities		(8.4)
Other Noncurrent Liabilities [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities	0.0	(2.0)
Operating lease liability
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities	0.0
Goodwill [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles		(30.5)
Other Intangible Assets
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles		$ 19.9
Goodwill [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments Related to Previous Period	(7.4)
Other Noncurrent Assets [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments Related to Previous Period	0.0
Other acquirees
Business Combinations [Abstract]
Finite-lived Intangible Assets Acquired	159.4
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	159.4
Goodwill, Acquired During Period	141.7
Providence Medical Foundation
Business Acquisition [Line Items]
Goodwill, Acquired During Period	25.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	0.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(55.8)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	(0.9)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(0.9)
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	0.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	29.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0.0
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	54.9
Escrow Deposit	0.0
Westpac Labs, Inc.
Business Acquisition [Line Items]
Goodwill, Acquired During Period	45.1
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	0.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(97.7)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	0.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(10.0)
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	0.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	1.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	50.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	10.0
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	87.7
Escrow Deposit	0.0
Cash Acquired in Excess of Payments to Acquire Business	0.0
Baystate Medical Center
Business Acquisition [Line Items]
Goodwill, Acquired During Period	70.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	0.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(157.5)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	(7.2)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(10.9)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	146.6
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	7.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	79.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	3.7
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	116.6
Escrow Deposit	30.0
Cash Acquired in Excess of Payments to Acquire Business	0.0
Other Acquisitions
Business Acquisition [Line Items]
Escrow Deposit	$ 0.0
Customer Lists \| Maximum [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	15 years
Customer Lists \| Minimum [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years

DEBT (Short-term borrowings and current portion of long-term debt) (Table) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Short-term Debt [Line Items]
Current debt excluding finance lease liability	$ 2,041.5	$ 999.8
Notes Payable	0.8	1.1
3.60% senior notes due 2025	0.0	1,000.0
4.00% senior notes due 2023	400.0	400.0
Short term debt issuance costs	(1.7)	(1.3)
Line of Credit, Current	42.4	0.0
Other Current Liabilities
Short-term Debt [Line Items]
3.60% senior notes due 2025	1,000.0	0.0
3.25% senior notes due 2024	$ 600.0	$ 600.0

BASIS OF FINANCIAL STATEMENT PRESENTATION	3 Months Ended
BASIS OF FINANCIAL STATEMENT PRESENTATION	Mar. 31, 2024
Accounting Policies [Abstract]
Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block]	BASIS OF FINANCIAL STATEMENT PRESENTATION Laboratory Corporation of America® Holdings (Labcorp® or the Company) is a global leader of innovative and comprehensive laboratory services that provides vital information to help doctors, hospitals, pharmaceuitcal companies, researchers, and patients make clear and confident decisions. By leveraging its unparalleled diagnostics and drug development capabilities, the Company provides insights and accelerates innovations to improve health and improve lives. The Company reports its business in two segments, Diagnostics Laboratories (Dx) and Biopharma Laboratory Services (BLS), formerly Drug Development. For further financial information about these segments, see Note 12 (Business Segment Information) to the Condensed Consolidated Financial Statements. During the three months ended March 31, 2024, Dx and BLS contributed approximately 78% and 22%, respectively, of revenues to the Company. During the three months ended March 31, 2023, Dx and BLS contributed approximately 78% and 22%, respectively, of revenues to the Company. The accompanying condensed consolidated financial statements of the Company are unaudited. In the opinion of management, all adjustments necessary for a fair statement of results of operations, cash flows, and financial position have been made. Except as otherwise disclosed, all such adjustments are of a normal recurring nature. Interim results are not necessarily indicative of results for a full year. The year-end condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by generally accepted accounting principles. The condensed consolidated financial statements and notes are presented in accordance with the rules and regulations of the Securities and Exchange Commission (SEC) and do not contain certain information included in the Company’s fiscal year 2023 Annual Report on Form 10-K (Annual Report). Therefore, these interim statements should be read in conjunction with the consolidated financial statements and notes thereto contained in the Company’s Annual Report. The condensed 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 20.0% and no representation on the investee's board of directors) are accounted for at fair value, or at cost minus impairment adjusted for observable price changes in orderly transactions for an identical or similar investment of the same issuer for those investments that do not have readily determinable fair values. All significant inter-company transactions and accounts have been eliminated. The Company does not have any significant variable interest entities or special purpose entities whose financial results are not included in the condensed consolidated financial statements. The financial statements of the Company's operating 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 period. Resulting translation adjustments are included in “Accumulated other comprehensive income (loss).”
Basis of Presentation and Significant Accounting Policies [Text Block]	BASIS OF FINANCIAL STATEMENT PRESENTATION Laboratory Corporation of America® Holdings (Labcorp® or the Company) is a global leader of innovative and comprehensive laboratory services that provides vital information to help doctors, hospitals, pharmaceuitcal companies, researchers, and patients make clear and confident decisions. By leveraging its unparalleled diagnostics and drug development capabilities, the Company provides insights and accelerates innovations to improve health and improve lives. The Company reports its business in two segments, Diagnostics Laboratories (Dx) and Biopharma Laboratory Services (BLS), formerly Drug Development. For further financial information about these segments, see Note 12 (Business Segment Information) to the Condensed Consolidated Financial Statements. During the three months ended March 31, 2024, Dx and BLS contributed approximately 78% and 22%, respectively, of revenues to the Company. During the three months ended March 31, 2023, Dx and BLS contributed approximately 78% and 22%, respectively, of revenues to the Company. The accompanying condensed consolidated financial statements of the Company are unaudited. In the opinion of management, all adjustments necessary for a fair statement of results of operations, cash flows, and financial position have been made. Except as otherwise disclosed, all such adjustments are of a normal recurring nature. Interim results are not necessarily indicative of results for a full year. The year-end condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by generally accepted accounting principles. The condensed consolidated financial statements and notes are presented in accordance with the rules and regulations of the Securities and Exchange Commission (SEC) and do not contain certain information included in the Company’s fiscal year 2023 Annual Report on Form 10-K (Annual Report). Therefore, these interim statements should be read in conjunction with the consolidated financial statements and notes thereto contained in the Company’s Annual Report. The condensed 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 20.0% and no representation on the investee's board of directors) are accounted for at fair value, or at cost minus impairment adjusted for observable price changes in orderly transactions for an identical or similar investment of the same issuer for those investments that do not have readily determinable fair values. All significant inter-company transactions and accounts have been eliminated. The Company does not have any significant variable interest entities or special purpose entities whose financial results are not included in the condensed consolidated financial statements. The financial statements of the Company's operating 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 period. Resulting translation adjustments are included in “Accumulated other comprehensive income (loss).”

COMMITMENTS AND CONTINGENCIES	3 Months Ended
COMMITMENTS AND CONTINGENCIES	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Unaudited) - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]
BALANCE at Dec. 31, 2022	$ 10,096.6	$ 8.1	$ 0.0	$ 10,581.7	$ (493.2)
Net earnings attributable to Laboratory Corporation of America Holdings	212.9	0.0	0.0	212.9	0.0
Other comprehensive earnings, net of tax	49.0	0.0	0.0	0.0	49.0
Dividends	64.7	0.0	0.0	64.7	0.0
Issuance of common stock under employee stock plans	(27.6)	0.0	(27.6)	0.0	0.0
Surrender of restricted stock and performance share awards	(20.5)	0.0	(20.5)	0.0	0.0
Stock compensation	40.6	0.0	40.6	0.0	0.0
BALANCE at Mar. 31, 2023	10,341.5	8.1	47.7	10,729.9	(444.2)
Retained Earnings (Accumulated Deficit)	7,888.2
BALANCE at Dec. 31, 2023	7,875.0	7.7	38.4	7,888.2	(59.3)
Net earnings attributable to Laboratory Corporation of America Holdings	228.0	0.0	0.0	228.0	0.0
Other comprehensive earnings, net of tax	(126.1)	0.0	0.0	0.0	(126.1)
Dividends	60.9	0.0	0.0	60.9	0.0
Issuance of common stock under employee stock plans	(26.7)	0.0	(26.7)	0.0	0.0
Surrender of restricted stock and performance share awards	(14.7)	0.0	(14.7)	0.0	0.0
Stock compensation	31.6	0.0	31.6	0.0	0.0
BALANCE at Mar. 31, 2024	7,959.6	$ 7.7	$ 82.0	$ 8,055.3	$ (185.4)
Retained Earnings (Accumulated Deficit)	$ 8,055.3

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of accumulated undistributed earnings (deficit).

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Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

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+ Details

REVENUE (Tables)

3 Months Ended

Mar. 31, 2024

Disaggregation of Revenue [Line Items]

Financing Receivable, Allowance for Credit Loss [Table Text Block]

The rollforward for the allowance for credit losses for the three months ended March 31, 2024, was as follows:


	Accounts Receivable		Unbilled Services		Note and Other Receivables		Total
Balance as of December 31, 2023	$	32.7	$	7.5	$	0.7	$	40.9
Plus, credit loss expense	2.4		—		—		2.4

Less, write offs	0.9		0.1		—		1.0
Balance as of March 31, 2024	$	34.2	$	7.4	$	0.7	$	42.3

Contract with Customer, Asset and Liability [Table Text Block]


	March 31, 2024		December 31, 2023
Dx accounts receivable	$	1,260.9	$	1,135.2
BLS accounts receivable	857.0		810.8
Less BLS allowance for doubtful accounts	(34.2)		(32.7)
Accounts receivable	$	2,083.7	$	1,913.3

Gross unbilled services	$	127.8	$	192.9
Less reserve for unbilled services	(7.4)		(7.5)
Unbilled services	$	120.4	$	185.4

Unearned revenue	$	377.5	$	421.7

Disaggregation of Revenue [Table Text Block]

The Company's revenues by segment and by payers/customer groups for the three months ended March 31, 2024, and 2023, were as follows:


	For the Three Months Ended March 31, 2024								For the Three Months Ended March 31, 2023
	North America		Europe		Other		Total		North America		Europe		Other		Total
Payer/Customer
Dx
Clients	25	%	—	%	—	%	25	%	25	%	—	%	—	%	25	%
Patients	10	%	—	%	—	%	10	%	9	%	—	%	—	%	9	%
Medicare and Medicaid	8	%	—	%	—	%	8	%	8	%	—	%	—	%	8	%
Third party	35	%	—	%	—	%	35	%	36	%	—	%	—	%	36	%
Total Dx revenues by payer	78	%	—	%	—	%	78	%	78	%	—	%	—	%	78	%
BLS




Pharmaceutical, biotechnology and medical device companies	9	%	9	%	4	%	22	%	9	%	9	%	4	%	22	%
Total revenues	87	%	9	%	4	%	100	%	87	%	9	%	4	%	100	%

Revenues in the U.S. were $2,654.6 (83.6%) and $2,557.4 (84.2%) for the three months ended March 31, 2024, and 2023, respectively.

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

BASIS OF FINANCIAL STATEMENT PRESENTATION (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Asset Impairment Charges	$ 2.5	$ 2.2
Revenues	3,176.6	$ 3,037.8
Contract with Customer, Liability	$ 377.5		$ 421.7
Percent of Revenue Contributed	100.00%	100.00%
Ownership percentage below which investments are generally accounted for on the cost method (in thousandths)	20.00%
Provision for income taxes	$ 69.1	$ 63.9
Net Income (Loss) Attributable to Parent	228.0	212.9
Stockholders' Equity Attributable to Parent	7,959.6	10,341.5	7,875.0	$ 10,096.6
Deferred Revenue, Revenue Recognized	51.0	$ 52.6
Cash and cash equivalents	$ 99.3		$ 536.8
LabCorp Diagnostics [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percent of Revenue Contributed	78.00%	78.00%

DEBT (Credit Facilities) (Details) - USD ($)	3 Months Ended
DEBT (Credit Facilities) (Details) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Line of Credit Facility [Line Items]
Revolving Credit Facility, maximum borrowing capacity	$ 1,000,000,000
Line of Credit Facility, Commitment Fee Description	0.10% to 0.225%
Notes Payable	$ 800,000	$ 1,100,000
Credit Facility Option to Increase	500,000,000.0
Credit Facility, Maximum Swing Line Borrowings	100,000,000.0
Letters of Credit Outstanding, Amount	90,700,000
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit Facility, Maximum Letters of Credit	$ 150,000,000.0
Line of Credit Facility, Interest Rate at Period End	6.42%

COMMITMENTS AND CONTINGENCIES (Details) $ in Millions	3 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) $ in Millions	Mar. 31, 2024 USD ($)
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value	$ 817.0
Enhanced Damages
Loss Contingencies [Line Items]
Loss Contingency, Damages Awarded, Value	100.0
Initial Damages
Loss Contingencies [Line Items]
Loss Contingency, Damages Awarded, Value	$ 272.0

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Provision for income taxes	$ 69.1	$ 63.9
Foreign currency translation adjustments	(124.3)	48.1
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	(2.4)	1.2
Other comprehensive earnings (loss) before tax	(126.7)	49.3
Tax effect of adjustments	0.6	(0.3)
Other comprehensive earnings (loss), net of tax	(126.1)	49.0
Net earnings	228.3	213.3
Comprehensive earnings	102.2	262.3
Less: Net earnings attributable to the noncontrolling interest	(0.3)	(0.4)
Comprehensive earnings attributable to Laboratory Corporation of America Holdings	$ 101.9	$ 261.9

GOODWILL AND INTANGIBLE ASSETS (Components of identifiable intangible assets) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	$ 5,149.2	$ 5,058.4
Finite-Lived Intangible Assets, Accumulated Amortization	(1,755.1)	(1,716.4)
Intangible Assets, Net (Excluding Goodwill)	3,394.1	3,342.0
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	3,945.3	3,868.6
Finite-Lived Intangible Assets, Accumulated Amortization	(1,395.7)	(1,367.2)
Intangible Assets, Net (Excluding Goodwill)	2,549.6	2,501.4
Patents, Licenses And Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	521.4	526.6
Finite-Lived Intangible Assets, Accumulated Amortization	(276.8)	(273.3)
Intangible Assets, Net (Excluding Goodwill)	244.6	253.3
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	152.4	130.3
Finite-Lived Intangible Assets, Accumulated Amortization	(65.9)	(60.4)
Intangible Assets, Net (Excluding Goodwill)	86.5	69.9
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	16.4	16.4
Finite-Lived Intangible Assets, Accumulated Amortization	(6.9)	(6.1)
Intangible Assets, Net (Excluding Goodwill)	9.5	10.3
Use Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	3.5	3.5
Finite-Lived Intangible Assets, Accumulated Amortization	(2.8)	(2.7)
Intangible Assets, Net (Excluding Goodwill)	0.7	0.8
Canadian licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	496.0	498.8
Finite-Lived Intangible Assets, Accumulated Amortization	0.0	0.0
Intangible Assets, Net (Excluding Goodwill)	496.0	498.8
In Process R&A and Media
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	14.2	14.2
Finite-Lived Intangible Assets, Accumulated Amortization	(7.0)	(6.7)
Intangible Assets, Net (Excluding Goodwill)	$ 7.2	$ 7.5

Discontinued Operations and Disposal Groups

3 Months Ended

Mar. 31, 2024

Discontinued Operations and Disposal Groups [Abstract]

Disposal Groups, Including Discontinued Operations, Disclosure

2. DISCONTINUED OPERATIONS

On June 30, 2023 (the Distribution Date), Labcorp completed the previously announced separation (the Separation) from the Company of Fortrea Holdings Inc. (Fortrea), formerly the Company's Clinical Development and Commercialization Services (CDCS) business, into a separate, publicly-traded company. All historical operating results of Fortrea are presented as Discontinued Operations, net of tax, in the consolidated statement of operations. The spin-off is expected to be treated as tax-free for the Company and its shareholders for U.S. federal income tax purposes.

A discontinued operation may include a component or a group of components of the Company's operations. A disposal of a component or a group of components is reported in discontinued operations if the disposal represents a strategic shift that has or will have a major effect on the Company's operations and financial results when the following occurs: (1) a component (or group of components) meets the criteria to be classified as held for sale; (2) the component or group of components is disposed of by sale; or (3) the component or group of components is disposed of other than by sale (for example, by abandonment or in a distribution to owners in a spin-off). For any component classified as held for sale or disposed of by sale or other than by sale, qualifying for presentation as a discontinued operation, the Company reports the results of operations of the discontinued operations (including any gain or loss recognized on the disposal or loss recognized on classification as held for sale of a discontinued operation), less applicable income taxes (benefit), as a separate component in the consolidated statement of operations for current and all prior periods presented. The Company also reports assets and liabilities associated with discontinued operations as separate line items on the consolidated balance sheet for prior periods.

The spin-off of Fortrea from Labcorp was achieved through the Company’s pro-rata distribution of 100% of the outstanding shares of Fortrea common stock to holders of record of Labcorp common stock. Each holder of record of Labcorp common stock received one share of Fortrea common stock for every share of Labcorp common stock held at 5:00 p.m., Burlington, North Carolina, time on June 20, 2023, the record date for the distribution.

In June 2023, Fortrea, prior to the Separation and while a subsidiary of the Company, issued $570.0 of 7.500% senior secured notes due 2030 (the Fortrea Notes). The proceeds from the Fortrea Notes were used to fund cash payments of approximately $1,600.0 to the Company in connection with the Separation. The Company does not guarantee the Fortrea Notes following the Separation. Also in June 2023, Fortrea entered into three floating secured overnight financing rate (SOFR) credit facilities totaling $1,520.0. These are comprised of a $450.0 Revolver maturing June 30, 2028; a $500.0 Term Loan A maturing June 30, 2028; and a $570.0 Term Loan B maturing June 30, 2030.

In connection with the spin-off, the Company entered into several agreements with Fortrea on or prior to the Distribution Date that, among other things, provide a framework for the Company’s relationship with Fortrea after the spin-off, including a separation and distribution agreement, a tax matters agreement, an employee matters agreement, and a transition services agreement. These agreements contain the key provisions relating to the spin-off, including provisions relating to the principal intercompany transactions required to effect the spin-off, the conditions to the spin-off and provisions governing the relationship between Fortrea and the Company after the spin-off. The costs to provide these services are included in operating income but the service fees are included in other income.

Financial Information of Discontinued Operations

Earnings from Discontinued Operations, Net of Tax in the Consolidated Statements of Operations reflect the after-tax results of Fortrea's business and Separation-related fees, and do not include any allocation of general corporate overhead expense or interest expense of the Company.

The following table summarizes the significant line items included in Earnings from Discontinued Operations, Net of Tax in the Consolidated Statements of Operations for the three months ended March 31, 2023:


	Three Months Ended March 31, 2023
Revenues	$	740.1
Cost of revenues	615.5
Gross profit	124.6
Selling, general and administrative expenses	96.4
Amortization of intangibles and other assets	15.9

Restructuring and other charges	1.1
Operating income	11.2
Other income (expense):



Other, net	(5.7)
Earnings before income taxes	5.5
Provision for income taxes	0.6


Net earnings attributable to Laboratory Corporation of America Holdings	$	4.9

BUSINESS SEGMENT INFORMATION Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Percent of Revenue Contributed	100.00%	100.00%
Revenues	$ 3,176.6	$ 3,037.8
Operating Income (Loss)	321.3	329.8
Amortization of Intangible Assets	(60.1)	(53.4)
Net Restructuring Charges	(5.0)	(7.5)
Goodwill and Intangible Asset Impairment	(2.5)	(2.2)
Operating Segments
Segment Reporting Information [Line Items]
Operating Income (Loss)	517.8	515.1
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenues	14.0	6.3
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)	$ (128.9)	$ (122.2)
LabCorp Diagnostics [Member]
Segment Reporting Information [Line Items]
Percent of Revenue Contributed	78.00%	78.00%
Diagnostics
Segment Reporting Information [Line Items]
Percent of Revenue Contributed	78.00%
Diagnostics \| Operating Segments
Segment Reporting Information [Line Items]
Revenues	$ 2,479.7	$ 2,382.8
Operating Income (Loss)	$ 417.9	441.5
Drug Development
Segment Reporting Information [Line Items]
Percent of Revenue Contributed	22.00%
Drug Development \| Operating Segments
Segment Reporting Information [Line Items]
Revenues	$ 710.9	661.3
Operating Income (Loss)	$ 99.9	$ 73.6

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY

3 Months Ended

Mar. 31, 2024

Stockholders' Equity Note [Abstract]

Changes in common shares issued and held in treasury

The changes in common shares issued are summarized below:


			Issued and Outstanding
Common shares at December 31, 2023			83.9
Shares issued under employee stock plans			0.4




Common shares at March 31, 2024			84.3

Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]

The components of accumulated other comprehensive earnings (loss) were as follows:


	Foreign Currency Translation Adjustments		Net Benefit Plan Adjustments		Accumulated Other Comprehensive Earnings (Loss)
Balance as of December 31, 2023	$	(47.6)	$	(11.7)	$	(59.3)

Current year adjustments	(124.3)		(1.5)		(125.8)

Amounts reclassified from accumulated other comprehensive income	—		(0.9)		(0.9)
Tax effect of adjustments	—		0.6		0.6
Balance as of March 31, 2024	$	(171.9)	$	(13.5)	$	(185.4)

Accumulated Other Comprehensive Income (Loss) [Line Items]

Preferred Stock and Common Shareholders' Equity

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 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 March 31, 2024, and December 31, 2023.

The changes in common shares issued are summarized below:


			Issued and Outstanding
Common shares at December 31, 2023			83.9
Shares issued under employee stock plans			0.4




Common shares at March 31, 2024			84.3

Share Repurchase Program

When the Company repurchases shares of Common Stock, the amount paid to repurchase the shares in excess of the par or stated value is allocated to additional paid-in-capital unless subject to limitation or the balance in additional paid-in-capital is exhausted. Remaining amounts are recognized as a reduction in retained earnings.

As of March 31, 2024, the Company had outstanding authorization from the board of directors to purchase up to $531.5 of the Company's common stock.

Dividends

For the three months ended March 31, 2024, the Company paid $62.1 in common stock dividends. On April 11, 2024, the Company announced a cash dividend of $0.72 per share of common stock for the first quarter, or approximately $61.4 in the aggregate. The dividend will be payable on June 12, 2024, to stockholders of record of all issued and outstanding shares of common stock as of the close of business on May 28, 2024. The declaration and payment of any future dividends will be at the discretion of the Company's board of directors.

Accumulated Other Comprehensive Earnings (Loss)

The components of accumulated other comprehensive earnings (loss) were as follows:


	Foreign Currency Translation Adjustments		Net Benefit Plan Adjustments		Accumulated Other Comprehensive Earnings (Loss)
Balance as of December 31, 2023	$	(47.6)	$	(11.7)	$	(59.3)

Current year adjustments	(124.3)		(1.5)		(125.8)

Amounts reclassified from accumulated other comprehensive income	—		(0.9)		(0.9)
Tax effect of adjustments	—		0.6		0.6
Balance as of March 31, 2024	$	(171.9)	$	(13.5)	$	(185.4)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

- Definition

The entire disclosure for equity.

+ References

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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

SUPPLEMENTAL CASH FLOW INFORMATION (Tables)

3 Months Ended

Mar. 31, 2024

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information


	Three Months Ended March 31,
	2024		2023

Cash paid during period for:
Interest	$	71.6	$	70.5
Income taxes, net of refunds	21.5		28.4
Disclosure of non-cash financing and investing activities:



Change in accrued property, plant, and equipment	(12.2)		(3.9)

Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2024	Apr. 29, 2024
Document Information [Table]
Entity Common Stock, Shares Outstanding		84,293,628
Entity Central Index Key	0000920148
Document Fiscal Year Focus	2024
Entity Registrant Name	LABORATORY CORPORATION OF AMERICA HOLDINGS
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		84,293,628
Document Fiscal Period Focus	Q1
Amendment Flag	false
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity File Number	1-11353
Entity Registrant Name	LABORATORY CORPORATION OF AMERICA HOLDINGS
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	13-3757370
Entity Address, Address Line One	358 South Main Street
Entity Address, City or Town	Burlington,
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27215
City Area Code	336
Local Phone Number	229-1127
Title of 12(b) Security	Common Stock, $0.10 par value
Trading Symbol	LH
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Document Fiscal Year Focus	2024
Current Fiscal Year End Date	--12-31
Entity Central Index Key	0000920148

REVENUE Disaggregated Revenue Table (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Accounts Receivable, Allowance for Credit Loss	$ 34.2		$ 32.7
Unbilled Services, Allowance for Credit Loss	7.4		7.5
Note Receivable, Allowance for Credit Loss	0.7		0.7
Allowance for Credit Loss	42.3		40.9
Current Expected Credit Losses Opening Balance Sheet Impact on Retained Earnings	2.4
Allowance for Credit Loss, Write Off	1.0
Deferred Revenue, Revenue Recognized	51.0	$ 52.6
Contract with Customer, Asset, before Allowance for Credit Loss	127.8		192.9
Contract with Customer, Liability	377.5		421.7
Unbilled Contracts Receivable	$ 120.4		185.4
Percent of Revenue Contributed	100.00%	100.00%
Revenues	$ 3,176.6	$ 3,037.8
Accounts Receivable, after Allowance for Credit Loss, Current	2,083.7		1,913.3
Allowance for Credit Loss, Receivable, Other, Current	(7.4)		(7.5)
Contract with Customer, Asset, after Allowance for Credit Loss, Current	$ 120.4		185.4
Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	9.00%	9.00%
North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	87.00%	87.00%
Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	4.00%	4.00%
UNITED STATES
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	83.60%	84.20%
Revenues	$ 2,654.6	$ 2,557.4
Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	8.00%	8.00%
LabCorp Diagnostics [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	78.00%	78.00%
LabCorp Diagnostics [Member] \| Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
LabCorp Diagnostics [Member] \| North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	78.00%	78.00%
LabCorp Diagnostics [Member] \| Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
LabCorp Diagnostics [Member] \| Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	25.00%	25.00%
LabCorp Diagnostics [Member] \| Client [Member] \| Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
LabCorp Diagnostics [Member] \| Client [Member] \| North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	25.00%	25.00%
LabCorp Diagnostics [Member] \| Client [Member] \| Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
LabCorp Diagnostics [Member] \| Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	10.00%	9.00%
LabCorp Diagnostics [Member] \| Self-Pay [Member] \| Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
LabCorp Diagnostics [Member] \| Self-Pay [Member] \| North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	10.00%	9.00%
LabCorp Diagnostics [Member] \| Self-Pay [Member] \| Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
LabCorp Diagnostics [Member] \| Medicare and Medicaid [Member] \| Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
LabCorp Diagnostics [Member] \| Medicare and Medicaid [Member] \| North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	8.00%	8.00%
LabCorp Diagnostics [Member] \| Medicare and Medicaid [Member] \| Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
LabCorp Diagnostics [Member] \| Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	35.00%	36.00%
LabCorp Diagnostics [Member] \| Third party [Member] \| Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
LabCorp Diagnostics [Member] \| Third party [Member] \| North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	35.00%	36.00%
LabCorp Diagnostics [Member] \| Third party [Member] \| Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0.00%	0.00%
Covance Drug Development [Member] \| Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		22.00%
Covance Drug Development [Member] \| Biopharmaceutical and medical device companies [Member] \| Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		9.00%
Covance Drug Development [Member] \| Biopharmaceutical and medical device companies [Member] \| North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		9.00%
Covance Drug Development [Member] \| Biopharmaceutical and medical device companies [Member] \| Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		4.00%
Diagnostics
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	78.00%
Accounts Receivable, before Allowance for Credit Loss	$ 1,260.9		1,135.2
Drug Development
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	22.00%
Accounts Receivable, before Allowance for Credit Loss	$ 857.0		$ 810.8
Drug Development \| Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	22.00%
Drug Development \| Biopharmaceutical and medical device companies [Member] \| Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	9.00%
Drug Development \| Biopharmaceutical and medical device companies [Member] \| North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	9.00%
Drug Development \| Biopharmaceutical and medical device companies [Member] \| Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	4.00%
Notes Receivable [Member]
Disaggregation of Revenue [Line Items]
Current Expected Credit Losses Opening Balance Sheet Impact on Retained Earnings	$ 0.0
Allowance for Credit Loss, Write Off	0.0
Unbilled Contracts Receivable [Member]
Disaggregation of Revenue [Line Items]
Current Expected Credit Losses Opening Balance Sheet Impact on Retained Earnings	0.0
Allowance for Credit Loss, Write Off	0.1
Accounts Receivable [Member]
Disaggregation of Revenue [Line Items]
Current Expected Credit Losses Opening Balance Sheet Impact on Retained Earnings	2.4
Allowance for Credit Loss, Write Off	$ 0.9

DEBT (Senior Notes) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 3,047.6	$ 4,054.7
Line of Credit Facility, Maximum Borrowing Capacity	1,000.0
Credit Facility Option to Increase	500.0
Credit Facility, Maximum Swing Line Borrowings	100.0
Long term debt issuance costs	24.4	26.3
Notes Payable	0.8	1.1
Foreign Currency Contract, Asset, Fair Value Disclosure		109.0
2.95% senior notes due 2029	650.0	650.0
Interest Rate Swap [Member]
Debt Instrument [Line Items]
2.70% senior notes due 2031	421.4	$ 430.4
Senior notes due 2027 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 600.0

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Accounts Receivable, after Allowance for Credit Loss, Current	$ 2,083,700,000	$ 1,913,300,000
Unbilled Contracts Receivable	120,400,000	185,400,000
Supplies inventories	475,000,000.0	474,600,000
Prepaid expenses and other	678,100,000	655,300,000
Total current assets	3,456,500,000	3,765,400,000
Property, plant and equipment, net	2,897,800,000	2,911,800,000
Goodwill, net	6,218,900,000	6,142,500,000
Intangible Assets, Net (Excluding Goodwill)	3,394,100,000	3,342,000,000
Joint venture partnerships and equity method investments	17,700,000	26,900,000
Other assets, net	546,000,000.0	536,500,000
Total assets	16,531,000,000	16,725,100,000
Liabilities, Current [Abstract]
Accounts Payable, Current	695,500,000	827,500,000
Accrued Liabilities, Current	649,300,000	804,000,000.0
Deferred Revenue, Current	377,500,000	421,700,000
Operating Lease, Liability, Current	171,300,000	165,800,000
Finance Lease, Liability, Current	6,400,000	6,400,000
Current debt excluding finance lease liability	2,041,500,000	999,800,000
Long-term debt, less current portion	3,941,500,000	3,225,200,000
Long-term Debt, Excluding Current Maturities	3,047,600,000	4,054,700,000
Commitments and contingent liabilities	468,200,000	409,300,000
Operating Lease, Liability, Noncurrent	624,600,000	648,900,000
Finance Lease, Liability, Noncurrent	77,100,000	78,600,000
Deferred income taxes and other tax liabilities	397,200,000	417,900,000
Noncontrolling interest	8,556,200,000	8,834,600,000
Shareholders' equity:
Common stock, 92.8 and 93.5 shares outstanding at March 31, 2013 and December 31, 2012, respectively	15,200,000	15,500,000
Additional paid-in capital	82,000,000.0	38,400,000
Retained earnings	7,700,000	7,700,000
Accumulated other comprehensive income	(8,055,300,000)	(7,888,200,000)
Total liabilities and shareholders' equity	(185,400,000)	(59,300,000)
Stockholders' Equity Attributable to Parent	7,959,600,000	7,875,000,000
Liabilities and Equity	16,531,000,000	16,725,100,000
Net earnings	228,300,000
Cash and cash equivalents	$ 99,300,000	$ 536,800,000