Accounting Policies [Abstract] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum [Member] Minimum [Member] Maximum [Member] Maximum [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Statement, Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Retained Earnings [Member] Retained Earnings [Member] Cash Flow Location [Axis] Cash Flow Location [Axis] Cash Flow Location [Axis] Cash Flow Location [Domain] Cash Flow Location [Domain] [Domain] for Cash Flow Location [Axis] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Equity Method Income (Loss), Net [Domain] Equity Method Income (Loss), Net [Domain] Equity Method Income (Loss), Net [Domain] Other Nonoperating Income (Expense) [Member] Other Nonoperating Income (Expense) [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Prospective Adoption of New Accounting Pronouncements [Axis] Prospective Adoption of New Accounting Pronouncements [Axis] Accounting Guidance [Domain] Accounting Guidance [Domain] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] LabCorp Diagnostics [Member] LabCorp Diagnostics [Member] LabCorp Diagnostics [Member] Covance Drug Development [Member] Covance Drug Development [Member] Covance Drug Development [Member] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Asset Impairment Charges Asset Impairment Charges Revenues Revenues Cost of Revenue Cost of Revenue Contract with Customer, Liability Contract with Customer, Liability Amortization of Deferred Sales Commissions Amortization of Deferred Sales Commissions Assets, Current Assets, Current Net Cash Provided by (Used in) Operating Activities Net Cash Provided by (Used in) Operating Activities Percent of Revenue Contributed Percent of Revenue Contributed Percent of Revenue Contributed Selling, general and administrative expenses Selling, General and Administrative Expense Nonoperating Income (Expense) Nonoperating Income (Expense) Provision for income taxes Income Tax Expense (Benefit) Net earnings Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net Income (Loss) Attributable to Parent Net Income (Loss) Attributable to Parent Basic earnings per common share (in dollars per share) Earnings Per Share, Basic Diluted earnings per common share (in dollars per share) Earnings Per Share, Diluted Net Cash Provided by (Used in) Investing Activities Net Cash Provided by (Used in) Investing Activities Net Cash Provided by (Used in) Financing Activities Net Cash Provided by (Used in) Financing Activities Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash and Cash Equivalents Assets Assets Long-term debt, less current portion Liabilities, Current Common stock, 92.8 and 93.5 shares outstanding at March 31, 2013 and December 31, 2012, respectively Noncontrolling Interest Mezzanine Equity Represents contractual value of a noncontrolling interest put (includes underlying noncontrolling interest). In February 2010, the Company completed a transaction to sell the partnership units acquired from the previous noncontrolling interest holder to a new Canadian partner. As a result of this transaction, the Company recorded a component of noncontrolling interest in liabilities and a component in mezzanine equity. This item represents the mezzanine equity component. Stockholders' Equity Attributable to Parent Stockholders' Equity Attributable to Parent Liabilities and Equity Liabilities and Equity Capitalized Contract Cost, Amortization Capitalized Contract Cost, Amortization Deferred Revenue, Revenue Recognized Deferred Revenue, Revenue Recognized Revenue, Remaining Performance Obligation, Amount Revenue, Remaining Performance Obligation, Amount Contract with Customer, Performance Obligation Satisfied in Previous Period Contract with Customer, Performance Obligation Satisfied in Previous Period Goodwill and Intangible Asset Impairment Goodwill and Intangible Asset Impairment Goodwill, Impairment Loss Goodwill, Impairment Loss Impairment of Intangible Assets (Excluding Goodwill) Impairment of Intangible Assets (Excluding Goodwill) impairment of floating rate note receivable impairment of floating rate note receivable impairment of floating rate note receivable Other than Temporary Impairment Losses, Investments Other than Temporary Impairment Losses, Investments Ownership percentage below which investments are generally accounted for on the cost method (in thousandths) Cost Method Investments Maximum Ownership Percentage This element represents the maximum ownership percentage of cost-method investments held by the Company. Generally, such investments do not have readily determinable fair values and are not required to be accounted for by the equity method. The carrying amount of such securities equates to cost, adjusted for other-than-temporary impairment. New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets Statement of Cash Flows [Abstract] Statement [Table] Statement [Table] Statement, Scenario [Axis] Scenario [Axis] Scenario [Domain] Scenario [Domain] Statement [Line Items] Statement [Line Items] CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net earnings to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Gain (Loss) on Disposition of Assets Gain (Loss) on Disposition of Assets Contingent consideration adjustment Contingent consideration adjustment Contingent consideration adjustment Depreciation And Amortization Of Leased Assets Depreciation And Amortization Of Leased Assets The amount of depreciation recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. Also, may include amortization charged against earnings for the periodic recognition of capitalized leases. Depreciation and amortization Depreciation, Depletion and Amortization Stock compensation Share-based Payment Arrangement, Noncash Expense Deferred income taxes Deferred Income Tax Expense (Benefit) Other Operating Activities, Cash Flow Statement Other Operating Activities, Cash Flow Statement Change in assets and liabilities (net of effects of acquisitions): Increase (Decrease) in Operating Capital [Abstract] Increase in accounts receivable (net) Increase (Decrease) in Accounts Receivable Increase (Decrease) in Unbilled Contract Receivable Increase (Decrease) in Unbilled Contract Receivable Increase (Decrease) in Unbilled Contract Receivable Increase in inventories Increase (Decrease) in Inventories Decrease in prepaid expenses and other Increase (Decrease) in Prepaid Expense and Other Assets Decrease in accounts payable Increase (Decrease) in Accounts Payable Increase (Decrease) in Deferred Revenue Increase (Decrease) in Deferred Revenue Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities Net cash provided by operating activities CASH FLOWS FROM INVESTING ACTIVITIES: Net Cash Provided by (Used in) Investing Activities [Abstract] Capital expenditures Payments to Acquire Property, Plant, and Equipment Proceeds from sale of assets Proceeds from Sale of Property, Plant, and Equipment Proceeds from Sale of Equity Method Investments Proceeds from Sale of Equity Method Investments Investments in equity affiliates Payments to Acquire Equity Method Investments Acquisition of businesses, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Net cash used for investing activities CASH FLOWS FROM FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from revolving credit facilities Proceeds from Long-term Lines of Credit Payment, Tax Withholding, Share-based Payment Arrangement Payment, Tax Withholding, Share-based Payment Arrangement Net proceeds from issuance of stock to employees Net proceeds from issuance of stock to employees The cash inflow associated with the amount received from holders exercising their stock options and employees related to shares purchased under the employee stock purchase plan. Payments for Repurchase of Common Stock Payments for Repurchase of Common Stock Other Financing Cash Flows Other Financing Cash Flows Other Financing Cash Flows Repayments of Lines of Credit Repayments of Lines of Credit Net cash provided by (used for) financing activities Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash and cash equivalents at beginning of period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of period Commitments and Contingencies Disclosure [Abstract] Loss Contingencies [Table] Loss Contingencies [Table] Investment, Name [Axis] Investment, Name [Axis] Investment, Name [Domain] Investment, Name [Domain] Covance [Member] Covance [Member] Covance [Member] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Number of Additional Parties Not Providing Consent Number of Additional Parties Not Providing Consent Number of Additional Parties Not Providing Consent Damages Per Violation Damages Per Violation Damages Per Violation Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Senior notes due 2045 [Member] Senior notes due 2045 [Member] Senior notes due 2045 [Member] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Segments [Axis] Segments [Domain] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Intangible Assets, Gross (Excluding Goodwill) Intangible Assets, Gross (Excluding Goodwill) Senior Notes, Noncurrent Senior Notes, Noncurrent Goodwill Goodwill Amortization of intangible assets Amortization of Intangible Assets Finite-Lived Intangible Assets, Future Amortization Expense Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Estimated amortization expense, 2012 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Estimated amortization expense, 2013 Finite-Lived Intangible Assets, Amortization Expense, Year Two Estimated amortization expense, 2014 Finite-Lived Intangible Assets, Amortization Expense, Year Three Estimated amortization expense, 2015 Finite-Lived Intangible Assets, Amortization Expense, Year Four Estimated amortization expense, 2016 Finite-Lived Intangible Assets, Amortization Expense, Year Five Estimated amortization expense, Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Restructuring Reserve [Abstract] Company's Restructuring Activities [Table] Schedule of Restructuring and Related Costs [Table] Restructuring Type [Axis] Restructuring Type [Axis] Type of Restructuring [Domain] Type of Restructuring [Domain] Severance and Other Employee Costs [Member] Employee Severance [Member] Lease and Other Facility Costs [Member] Facility Closing [Member] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Unused facility restructuring reserves Unused facility restructuring reserves Unused facility restructuring reserves Balance, beginning of period Restructuring Reserve Restructuring charges Restructuring Charges Reduction of prior restructuring accruals Restructuring Reserve, Accrual Adjustment Cash payments and other adjustments Restructuring Reserve Settled With Cash And Other Adjustment Amount of cash paid and/or consideration other than cash paid in the period to fully or partially settle a specified, previously accrued type of restructuring cost. Balance, end of period Current Restructuring Reserve, Current Non-current Restructuring Reserve, Noncurrent Total Restructuring Reserve Employee Severance Benefits Related Restructuring Reserve Accrual Adjustment Employee Severance Benefits Related Restructuring Reserve Accrual Adjustment Amount of any reversal and other adjustment made during the period to the amount of a previously accrued liability for employee severance benefits related restructuring costs, excluding adjustments for costs incurred during the period, costs settled during the period, and foreign currency translation adjustments. Income Statement [Abstract] Scenario [Axis] Gross Profit Gross Profit Amortization of intangibles and other assets Net restructuring and other special charges Net restructuring and other special charges Amount charged against earnings in the period for incurred and estimated costs, excluding asset retirement obligations, associated with exit from or disposal of business activities or restructurings pursuant to a program planned and controlled by management, and materially changes either the scope or manner of conduct of a business undertaken. Also, may include reversals and other adjustments to accrued liabilities and special charges, if any, for asset abandonment, uncollectible balances, etc. Operating Income (Loss) Operating Income (Loss) Other income (expenses): Nonoperating Income (Expense) [Abstract] Interest expense Interest Expense Equity method income, net Income (Loss) from Equity Method Investments Investment income Investment Income, Net Other, net Other Nonoperating Income (Expense) Earnings before income taxes Income (Loss) from Continuing Operations Before Income Taxes and Noncontrolling Interest Income (Loss) from Continuing Operations Before Income Taxes and Noncontrolling Interest Less: Net earnings attributable to the noncontrolling interest Net Income (Loss) Attributable to Noncontrolling Interest Net earnings attributable to Laboratory Corporation of America Holdings Recently Adopted Accounting Guidance [Policy Text Block] Recently Adopted Accounting Guidance [Policy Text Block] Recently Adopted Accounting Guidance [Policy Text Block] Cover [Abstract] Document Information [Table] Document Information [Table] Document Information, Document [Axis] Document Information, Document [Axis] Document [Domain] Document [Domain] Document Information [Line Items] Document Information [Line Items] Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Document Type Document Type Document Quarterly Report Document Quarterly Report Document Period End Date Document Period End Date Document Transition Report Document Transition Report Entity File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Statement of Financial Position [Abstract] Accounts Payable, Current Accounts Payable, Current ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Accounts Receivable, after Allowance for Credit Loss, Current Accounts Receivable, after Allowance for Credit Loss, Current Unbilled Contracts Receivable Unbilled Contracts Receivable Supplies inventories Inventory, Net Prepaid expenses and other Prepaid Expense, Current Total current assets Property, plant and equipment, net Property, Plant and Equipment, Net Goodwill, net Intangible Assets, Net (Excluding Goodwill) Intangible Assets, Net (Excluding Goodwill) Joint venture partnerships and equity method investments Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Deferred Income Taxes and Other Assets, Current Deferred Income Taxes and Other Assets, Current Other assets, net Other Assets, Noncurrent Total assets LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities and Equity [Abstract] Liabilities, Current [Abstract] Liabilities, Current [Abstract] Accrued Liabilities, Current Accrued Liabilities, Current Deferred Revenue, Current Deferred Revenue, Current Operating Lease, Liability, Current Operating Lease, Liability, Current Finance Lease, Liability, Current Finance Lease, Liability, Current Debt, Current Debt, Current Long-term Debt, Excluding Current Maturities Long-term Debt, Excluding Current Maturities Commitments and contingent liabilities Other Liabilities, Noncurrent Operating Lease, Liability, Noncurrent Operating Lease, Liability, Noncurrent Finance Lease, Liability, Noncurrent Finance Lease, Liability, Noncurrent Deferred income taxes and other tax liabilities Deferred income taxes and other tax liabilities Represents the noncurrent portion of deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax, combined with the noncurrent portion of the amount recognized for uncertain tax positions as of the balance sheet date. A noncurrent taxable temporary difference is a difference between the tax basis and the carrying amount of a noncurrent asset or liability in the financial statements prepared in accordance with generally accepted accounting principles. In a classified statement of financial position, an enterprise shall separate deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference. Noncontrolling interest Liabilities Shareholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Additional paid-in capital Additional Paid in Capital, Common Stock Retained earnings Common Stock, Value, Issued Accumulated other comprehensive income Retained Earnings (Accumulated Deficit) Total liabilities and shareholders' equity Accumulated Other Comprehensive Income (Loss), Net of Tax Stockholders' Equity Attributable to Parent Liabilities and Equity Postemployment Benefits [Abstract] Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Pension and Other Postretirement Plans Costs [Member] Pension and Other Postretirement Plans Costs [Member] Pension Plan [Member] Pension Plan [Member] Defined Benefit Plan Disclosures [Line Items] Defined Benefit Plan Disclosure [Line Items] Minimum non-elective contribution (NEC) % for the 401(K) plan (in hundredths) Non Elective Contribution The minimum non-elective contribution % by the company to all employees eligible for the defined contribution retirement plan. Contributions are concurrent with each payroll period and are non-forfeitable and vest immediately. Discretionary Contribution Percentage Maximum Discretionary Contribution Percentage Maximum The maximum discretionary contribution % by the company for eligible employees based on service. Defined contribution retirement plan cost Defined Contribution Plan, Cost Defined Benefit Plan and Postretirement Plan Disclosure Defined Benefit Plan [Abstract] Schedule of Pensions and Postretirement Plans Schedule of Defined Benefit Plans Disclosures [Table Text Block] Pension And Postretirement Plans Pension and Other Postretirement Benefits Disclosure [Text Block] Service cost for benefits earned Defined Benefit Plan, Service Cost Interest cost on benefit obligation Defined Benefit Plan, Interest Cost Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Net amortization and deferral Net Defined Benefit Plan Amortization And Deferral Net Defined Benefit Plan Amortization And Deferral Defined benefit/postretirement plan costs Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation Defined Benefit Plan, Funded (Unfunded) Status of Plan Defined Benefit Plan, Funded (Unfunded) Status of Plan Stockholders' Equity Note [Abstract] Changes in common shares issued and held in treasury Changes In Common Shares Issued And Held In Treasury [Table Text Block] Schedule is used to show the changes in common shares issued and held in treasury by the entity. Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Equity Components [Axis] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Preferred Stock and Common Shareholders' Equity Stockholders' Equity Note Disclosure [Text Block] New Accounting Pronouncements, Policy [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] Debt Disclosure [Abstract] Line of Credit Facility [Table] Line of Credit Facility [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] Prime Rate [Member] Prime Rate [Member] London Interbank Offered Rate (LIBOR) [Member] London Interbank Offered Rate (LIBOR) [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Term Loan and Revolving Credit Facility [Member] Term Loan and Revolving Credit Facility [Member] Term Loan and Revolving Credit Facility [Member] 2019 Term Loan [Member] 2019 Term Loan [Member] 2019 Term Loan [Member] Revolving Credit Facility [Member] Revolving Credit Facility [Member] Short-term Debt, Type [Axis] Short-term Debt, Type [Axis] Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Senior notes due 2027 [Member] Senior notes due 2027 [Member] Senior notes due 2027 [Member] Senior notes due 2024 [Member] [Member] Senior notes due 2024 [Member] [Member] Senior notes due 2024 [Member] Senior notes due 2020 [Member] Senior notes due 2020 [Member] A senior note is a bond that takes priority over other debt securities sold by the issuer. In the event the issuer goes bankrupt, senior debt holders receive priority for [must receive] repayment [prior] relative to junior and unsecured (general) creditors. Senior notes due 2022 [Member] Senior notes due 2022 [Member] Senior notes due 2022 [Member] Lender Name [Axis] Lender Name [Axis] Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] 2019 Term Loan 2019 Term Loan 2019 Term Loan Line of Credit Facility, Remaining Borrowing Capacity Line of Credit Facility, Remaining Borrowing Capacity Debt to EBITDA (Leverage) Ratio Next Three Quarters Debt to EBITDA (Leverage) Ratio Next Three Quarters Debt to EBITDA (Leverage) Ratio Next Three Quarters Debt to EBITDA (Leverage) Ratio Quarter Ending 1 Year From Present Debt to EBITDA (Leverage) Ratio Quarter Ending 1 Year From Present Debt to EBITDA (Leverage) Ratio Quarter Ending 1 Year From Present Quarter End Senior Notes Became Due During Quarter Senior Notes Became Due During Quarter Senior Notes Became Due During Quarter Debt Instrument, Interest Rate, Stated Percentage Debt Instrument, Interest Rate, Stated Percentage Credit Facility, Maximum Letters of Credit Credit Facility, Maximum Letters of Credit Credit Facility, Maximum Letters of Credit Line of Credit Facility, Fair Value of Amount Outstanding Line of Credit Facility, Fair Value of Amount Outstanding Revolving Credit Facility, maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Debt Instrument, Interest Rate, Effective Percentage Debt Instrument, Interest Rate, Effective Percentage Line of Credit Facility, Interest Rate Description Line of Credit Facility, Interest Rate Description Line of Credit Facility, Interest Rate at Period End Line of Credit Facility, Interest Rate at Period End Notes Payable Notes Payable, Current Credit Facility Option to Increase Credit Facility Option to Increase Credit Facility Option to Increase Credit Facility, Maximum Swing Line Borrowings Credit Facility, Maximum Swing Line Borrowings Credit Facility, Maximum Swing Line Borrowings Notes Payable Notes Payable Revolving Credit Facility Accrue Interest per Annum at Libor Plus Margin Percentage Revolving Credit Facility Accrue Interest per Annum at Libor Plus Margin Percentage Revolving Credit Facility Accrue Interest per Annum at Libor Plus Margin Percentage Revolving Credit Facility Accrue Interest Per Annum Base Rate Plus Percentage Revolving Credit Facility Accrue Interest Per Annum Base Rate Plus Percentage Revolving Credit Facility Accrue Interest Per Annum Base Rate Plus Percentage Revolving Credit Facility Fee Percentage Required to Pay on Outstanding Commitments Revolving Credit Facility Fee Percentage Required to Pay on Outstanding Commitments Revolving Credit Facility Fee Percentage Required to Pay on Outstanding Commitments Term Loan Accrue Interest per Annum at Libor Plus Margin Percentage Term Loan Accrue Interest per Annum at Libor Plus Margin Percentage Term Loan Accrue Interest per Annum at Libor Plus Margin Percentage Term Loan Accrue Interest Per Annum Base Rate Plus Percentage Term Loan Accrue Interest Per Annum Base Rate Plus Percentage Term Loan Accrue Interest Per Annum Base Rate Plus Percentage Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Subsequent Event [Line Items] Subsequent Event [Line Items] Schedule of Business Acquisitions, by Acquisition [Abstract] Schedule of Business Acquisitions, by Acquisition [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Business Acquisition [Line Items] Business Acquisition [Line Items] Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Business Acquisitions, by Acquisition [Table Text Block] Business Acquisition, Pro Forma Information [Table Text Block] Business Acquisition, Pro Forma Information [Table Text Block] Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Income Tax Disclosure [Abstract] Effective Income Tax Rate Reconciliation, Tax Contingency, Percent Effective Income Tax Rate Reconciliation, Tax Contingency, Percent Gross unrecognized income tax benefits Unrecognized Tax Benefits Accrued interest and penalties related to unrecognized income tax benefits Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Other Comprehensive Earnings, Net of Tax Other Comprehensive Income (Loss), Net of Tax [Abstract] Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax Other comprehensive earnings (loss) before tax Other Comprehensive Income (Loss), before Tax Tax effect of adjustments Other Comprehensive Income (Loss), Tax Other comprehensive earnings (loss), net of tax Other Comprehensive Income (Loss), Net of Tax Comprehensive earnings Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive earnings attributable to Laboratory Corporation of America Holdings Comprehensive Income (Loss), Net of Tax, Attributable to Parent Business Combinations [Abstract] Business Combination Disclosure [Text Block] Business Combination Disclosure [Text Block] Business Combination Purchase Price Allocation [Table] Business Combination Purchase Price Allocation [Table] Business Combination Purchase Price Allocation [Table] Nonrecurring Adjustment [Axis] Nonrecurring Adjustment [Axis] Nonrecurring Adjustment [Domain] Nonrecurring Adjustment [Domain] Trademarks and Trade Names [Member] Trademarks and Trade Names [Member] Cash and Cash Equivalents [Member] Cash and Cash Equivalents [Member] Accounts Receivable [Member] Accounts Receivable [Member] Other Current Assets [Member] Other Current Assets [Member] Inventories [Member] Inventories [Member] Prepaid Expenses and Other Current Assets [Member] Prepaid Expenses and Other Current Assets [Member] Property, Plant and Equipment [Member] Property, Plant and Equipment [Member] Deferred Tax Asset [Domain] Deferred Tax Asset [Domain] Goodwill [Member] Goodwill [Member] Customer Relationships [Member] Customer Relationships [Member] Other Noncurrent Assets [Member] Other Noncurrent Assets [Member] Assets [Member] Assets [Member] Accounts Payable [Member] Accounts Payable [Member] Accrued Liabilities [Member] Accrued Liabilities [Member] Deferred Revenue [Domain] Deferred Revenue [Domain] Other Liabilities [Member] Other Liabilities [Member] Other Noncurrent Liabilities [Member] Other Noncurrent Liabilities [Member] Liability [Member] Liability [Member] Trade Names [Member] Trade Names [Member] Use Rights [Member] Use Rights [Member] Envigo [Member] Envigo [Member] Envigo [Member] Business Combination Purchase Price Allocation [Line Items] Business Combination Purchase Price Allocation [Line Items] [Line Items] for Business Combination Purchase Price Allocation [Table] Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Operating Income (Loss) Net Income (Loss) Attributable to Parent Goodwill Cash payments for laboratory-related assets Payments to Acquire Businesses, Net of Cash Acquired Notes Receivable, Fair Value Disclosure Notes Receivable, Fair Value Disclosure Total acquisition consideration (cash, stock, notes, etc.) Total acquisition consideration (cash, stock, notes, etc.) Total acquisition consideration (cash, stock, notes, etc.) Gain (Loss) on Disposition of Assets Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets Indefinite-Lived Trade Names Indefinite-Lived Trade Names Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Statement of Stockholders' Equity [Abstract] Common Stock [Member] Common Stock [Member] Additional Paid-in Capital [Member] Additional Paid-in Capital [Member] Treasury Stock [Member] Treasury Stock [Member] Accumulated Other Comprehensive Income [Member] AOCI Attributable to Parent [Member] New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets BALANCE Net earnings attributable to Laboratory Corporation of America Holdings Other comprehensive earnings, net of tax Issuance of common stock under employee stock plans Issuance of common stock under employee plans Aggregate change in value for stock issued in period under ESPP combined with the value of stock issued as a result of option exercises. Surrender of restricted stock and performance share awards Stock Issued During Period, Value, Restricted Stock Award, Forfeitures Conversion of zero-coupon convertible debt Conversion of zero-coupon convertible debt Value of stock issued during the period upon the conversion of convertible securities (zero-coupon subordinated notes) and/or reversal of deferred tax liability to reflect the tax benefit realized upon issuance of the stock. Stock compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Purchase of common stock Stock Repurchased During Period, Value BALANCE Amount of Deferred Costs Related to Long-term Contracts Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Corporate Segment [Member] Corporate Segment [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Intercompany revenue elimination Intercompany revenue elimination Intercompany revenue elimination Earnings before income taxes Provision for income taxes Income Loss from Continuing Operations Before Income Taxes and Minority Interest Sum of operating profit and nonoperating income (expense) before income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest. Net earnings Net income attributable to Laboratory Corporation of America Holdings Discontinued Operations and Disposal Groups [Abstract] Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Group Name [Domain] Disposal Group Name [Domain] Disposal Group Classification [Axis] Disposal Group Classification [Axis] Disposal Group Classification [Domain] Disposal Group Classification [Domain] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Cash and cash equivalents Leases [Abstract] Supplemental Cash Flow Information Cash Flow, Supplemental Disclosures [Text Block] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Debt Debt Disclosure [Text Block] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Class of Stock [Line Items] Class of Stock [Line Items] Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased Rollforward of common shares issued Common Shares Issued Rollforward [Abstract] Common shares issued, beginning balance (in shares) Common Stock, Shares, Issued Commons Stock Issued During Period Shares Employee Stock Plans Commons Stock Issued During Period Shares Employee Stock Plans Number of common shares issued during the period as a result of an employee stock purchase plan and/or stock option plan. Stock Repurchased and Retired During Period, Shares Stock Repurchased and Retired During Period, Shares Common shares issued, ending balance (in shares) Common Stock, Shares, Issued Stock Repurchased During Period, Shares Stock Repurchased During Period, Shares Common stock repurchase average purchase price per share Common stock repurchase average purchase price per share Common stock repurchase average purchase price per share Payments for Repurchase of Common Stock Rollforward of Share Repurchase Program Outstanding Stock Repurchase Authorization [Abstract] Outstanding common stock repurchase authorization, beginning balance Common Stock Repurchase Authorization Outstanding The dollar amount of share (common shares) repurchase authorization approved by the Board of Directors which remains available to the Company. Outstanding common stock repurchase authorization, ending balance Common Shares Outstanding Rollforward [Abstract] Common Shares Outstanding Rollforward [Abstract] Common shares outstanding, beginning balance (in shares) Common Stock, Shares, Outstanding Common shares outstanding, ending balance (in shares) Rollforward of common shares held in treasury Common Shares Held In Treasury Rollforward [Abstract] Treasury Stock, Carrying Basis Treasury Stock, Carrying Basis Common Stock, Shares Authorized Common Stock, Shares Authorized Common Stock, Par or Stated Value Per Share Common Stock, Par or Stated Value Per Share Preferred Stock, Shares Authorized Preferred Stock, Shares Authorized Preferred Stock, Par or Stated Value Per Share Preferred Stock, Par or Stated Value Per Share Preferred Stock, Shares Outstanding Preferred Stock, Shares Outstanding Equity [Abstract] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax Other Comprehensive Income (Loss), before Reclassifications, before Tax Other Comprehensive Income (Loss), before Reclassifications, before Tax Accumulated Other Comprehensive Earnings [Roll Forward] Accumulated Other Comprehensive Earnings [Roll Forward] Accumulated Other Comprehensive Earnings [Roll Forward] Foreign Currency Translation Adjustments, Beginning balance Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Other comprehensive income before reclassifications Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss), before Reclassification and Tax Tax effect of adjustments Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax Foreign Currency Translation Adjustments, Ending balance Net Benefit Plan Adjustments, Beginning balance Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax Tax effect of adjustments Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Net Benefit Plan Adjustments, Ending balance Accumulated Other Comprehensive Earnings, Beginning balance Other comprehensive income before reclassifications Accumulated Other Comprehensive Earnings, Ending balance Schedule of Finite-Lived Intangible Assets by Major Class [Table] Schedule Of Other Intangible Assets By Major Class [Axis] Schedule Of Other Intangible Assets By Major Class [Axis] Schedule Of Other Intangible Assets By Major Class [Domain] Schedule Of Other Intangible Assets By Major Class [Domain] Patents, Licenses And Technology [Member] Patents, Licenses And Technology [Member] Patents are the exclusive legal right granted by the government to the owner of the patent to exploit an invention or a process for a period of time specified by law. Licenses are rights, generally of limited duration, under a license arrangement (for example, to sell or otherwise utilize specified products or processes in a specified territory). Technology-based intangible assets are innovations or scientific advances that have not been patented. Noncompete Agreements [Member] Noncompete Agreements [Member] Canadian licenses [Member] Licensing Agreements [Member] Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Intangible Assets, Net (Excluding Goodwill) Cash Payment Received Appropriated by U.S. Congress Covid-19 Cash Payment Received Appropriated by U.S. Congress Covid-19 Cash Payment Received Appropriated by U.S. Congress Covid-19 Noncontrolling Interest Puts [Abstract] Noncontrolling Interest Puts [Abstract] Noncontrolling Interest [Table] Noncontrolling Interest [Table] Noncontrolling Interest [Line Items] Noncontrolling Interest [Line Items] Supplemental Cash Flow Information [Abstract] Supplemental Cash Flow Information Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Disaggregated Revenue Table [Abstract] Disaggregated Revenue Table [Abstract] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] Other countries [Member] Other countries [Member] Other countries [Member] UNITED KINGDOM UNITED KINGDOM CANADA CANADA SWITZERLAND SWITZERLAND Europe [Member] Europe [Member] UNITED STATES UNITED STATES Contract with Customer, Sales Channel [Axis] Contract with Customer, Sales Channel [Axis] Contract with Customer, Sales Channel [Domain] Contract with Customer, Sales Channel [Domain] Self-Pay [Member] Self-Pay [Member] Client [Member] Client [Member] Client [Member] Medicare and Medicaid [Member] Medicare and Medicaid [Member] Medicare and Medicaid [Member] Third party [Member] Third party [Member] Third party [Member] Biopharmaceutical and medical device companies [Member] Biopharmaceutical and medical device companies [Member] Biopharmaceutical and medical device companies [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Financing Receivable, Allowance for Credit Loss [Table Text Block] Financing Receivable, Allowance for Credit Loss [Table Text Block] Contract with Customer, Asset and Liability [Table Text Block] Contract with Customer, Asset and Liability [Table Text Block] Revenue from Contract with Customer [Text Block] Revenue from Contract with Customer [Text Block] Disaggregation of Revenue [Table Text Block] Disaggregation of Revenue [Table Text Block] Capitalized Contract Cost [Table Text Block] Capitalized Contract Cost [Table Text Block] Other acquirees [Member] Other acquirees [Member] Other acquirees [Member] Goodwill, Acquired During Period Goodwill, Acquired During Period Business Acquisition, Pro Forma Revenue Business Acquisition, Pro Forma Revenue Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Finite-lived Intangible Assets Acquired Finite-lived Intangible Assets Acquired Business Acquisition, Pro Forma Net Income (Loss) Business Acquisition, Pro Forma Net Income (Loss) Fair Value Disclosures [Abstract] Company's population of financial assets and liabilities subject to fair value measurements Fair Value, Liabilities Measured on Recurring Basis [Table Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments, Gain (Loss) by Hedging Relationship [Table] Derivative Instruments, Gain (Loss) [Table] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Cross currency swap maturing 2022 [Member] Cross currency swap maturing 2022 [Member] Cross currency swap maturing 2022 [Member] Senior notes due 2025 [Member] [Member] Cross currency swap maturing 2025 [Member] Cross currency swap maturing 2025 [Member] Senior Long Term Notes Due2020 Member Senior Long Term Notes Due2020 Member A senior note is a bond that takes priority over other debt securities sold by the issuer. In the event the issuer goes bankrupt, senior debt holders receive priority for [must receive] repayment [prior] relative to junior and unsecured (general) creditors. Senior notes due 2025 [Member] [Member] Senior notes due 2025 [Member] [Member] Senior notes due 2025 [Member] [Member] Derivative Instruments, Gain (Loss) by Derivative Instrument Risk [Axis] Derivative Instrument [Axis] Derivative Contract Type [Domain] Derivative Contract [Domain] Interest Rate Swap [Member] Interest Rate Swap [Member] Currency Swap [Member] Currency Swap [Member] Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss) Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss) Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net 4.625% Senior notes due 2020 Short-term Debt, Fair Value Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge Fair Value Hedge Assets Fair Value Hedge Assets Derivative, Notional Amount Derivative, Notional Amount Debt Instrument, Basis Spread on Variable Rate Debt Instrument, Basis Spread on Variable Rate Foreign Currency Contract, Asset, Fair Value Disclosure Foreign Currency Contract, Asset, Fair Value Disclosure Foreign Currency Contracts, Liability, Fair Value Disclosure Foreign Currency Contracts, Liability, Fair Value Disclosure Fair Value Hedge Liabilities Fair Value Hedge Liabilities Derivative Instruments, Gain (Loss) [Table Text Block] Derivative Instruments, Gain (Loss) [Table Text Block] Derivative Instruments And Hedging Activities Derivative Instruments and Hedging Activities Disclosure [Text Block] Schedule of Derivative Instruments [Table Text Block] Schedule of Derivative Instruments [Table Text Block] Fair Value Measurements Fair Value Disclosures [Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Senior notes due 2023 [Member] Senior notes due 2023 [Member] Senior notes due 2023 [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Long-term Debt [Text Block] Schedule of Long-term Debt Instruments [Table Text Block] Debt Instrument, Interest Rate, Effective Percentage Stated interest rate percentage Line of Credit Facility, Maximum Borrowing Capacity Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Basis of Presentation and Significant Accounting Policies [Text Block] Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Earnings Per Share [Abstract] Earnings Per Share Earnings Per Share [Text Block] Derivative Instruments and Hedging [Abstract] Derivative Instruments and Hedging [Abstract] Use of Estimates, Policy [Policy Text Block] Use of Estimates, Policy [Policy Text Block] Debt Conversion [Table] Debt Conversion [Table] Debt Conversion [Line Items] Debt Conversion [Line Items] Decrease in Capital Expenditures Incurred but not yet Paid Decrease in Capital Expenditures Incurred but not yet Paid Decrease in Capital Expenditures Incurred but not yet Paid Capital Expenditures Incurred but Not yet Paid Capital Expenditures Incurred but Not yet Paid Cash paid during period for: Cash Paid During Period For [Abstract] Interest Interest Paid In Cash The amount of cash paid during the current period for interest owed on money borrowed Income taxes, net of refunds Income Taxes Paid, Net Disclosure of non-cash financing and investing activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Restructuring and Related Activities [Abstract] Schedule of Restructuring and Related Costs [Table] Restructuring Plan [Axis] Restructuring Plan [Axis] Restructuring Plan [Domain] Restructuring Plan [Domain] Other Comprehensive Income Location [Axis] Other Comprehensive Income Location [Axis] Other Comprehensive Income Location [Domain] Other Comprehensive Income Location [Domain] Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Novel Coranvirus (Covid-19) Financial Statement Impact [Policy Text Block] Novel Coranvirus (Covid-19) Financial Statement Impact [Policy Text Block] Novel Coranvirus (Covid-19) Financial Statement Impact [Policy Text Block] Segment Reconciliation of Operating Income to Consolidated [Abstract] Segment Reconciliation of Operating Income to Consolidated [Abstract] Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] Schedule of Short-term Debt [Table] Schedule of Short-term Debt [Table] Short-term Debt [Line Items] Short-term Debt [Line Items] Total short-term borrowings and current portion of long-term debt Short-term borrowings and current portion of long-term debt Schedule of Short-term Debt [Table Text Block] Restatement [Axis] Restatement [Axis] Restatement [Domain] Restatement [Domain] Accounts Receivable, Allowance for Credit Loss Accounts Receivable, Allowance for Credit Loss Current Assets: Shareholders' Equity: Common stock, shares outstanding (in shares) Reconciliation of Basic earnings per Share to Diluted Earnings per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Potential common shares not included in computation of diluted earnings per share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Segment Reporting [Abstract] Income Taxes Income Tax Disclosure [Text Block] Stock options (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Fair Value, Liabilities Measured on Recurring Basis [Table] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Liabilities Measured on Recurring Basis, Disclosure Items [Axis] Fair Value, Liabilities Measured on Recurring Basis, Disclosure Items [Domain] Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Number of Measurement Funds Available For Participant Election Number of Measurement Funds Available For Participant Election Number of Measurement Funds Available For Participant Election Noncontrolling interest puts Fair Value Liabilities Measured On Recurring Basis Noncontrolling Interest Puts This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis. Fair market value of senior notes Senior Notes Fair Value Estimated fair value of the debt instrument (senior notes) at the balance-sheet date Cash Surrender Value, Fair Value Disclosure Cash Surrender Value, Fair Value Disclosure Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability Contingent Consideration Classified as Equity, Fair Value Disclosure Contingent Consideration Classified as Equity, Fair Value Disclosure Fair Value Hedges, Net Fair Value Hedges, Net Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Contingent consideration adjustment Equity Securities, FV-NI Equity Securities, FV-NI Debt Instrument, Interest Rate, Effective Percentage Zero Coupon Convertible Subordinated Notes [Table] Zero Coupon Convertible Subordinated Notes [Table] Zero Coupon Convertible Subordinated Notes [Table] Zero Coupon Convertible Subordinated Notes [Line Items] Zero Coupon Convertible Subordinated Notes [Line Items] Zero Coupon Convertible Subordinated Notes [Line Items] Changes in Carrying Amount of Goodwill Schedule of Goodwill [Table Text Block] Schedule of Intangible Assets and Goodwill [Table Text Block] Schedule of Intangible Assets and Goodwill [Table Text Block] Segment Reporting Disclosure [Text Block] Segment Reporting Disclosure [Text Block] Retirement Benefits [Abstract] Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Domain] Defined Benefit Plan, Plan Assets, Category [Domain] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Non Elective Contribution Discretionary Contribution Percentage Minimum Discretionary Contribution Percentage Minimum Discretionary contribution percentage by the company for eligible employees based on service, range minimum. Defined Contribution Plan, Cost Defined Contribution Plan Total Expense Defined Contribution Plan Total Expense Defined Contribution Plan Total Expense Defined Contribution Plan, Employer Matching Contribution, Percent of Match Defined Contribution Plan, Employer Matching Contribution, Percent of Match Restructuring and Related Activities Disclosure [Text Block] Restructuring and Related Activities Disclosure [Text Block] Income [Abstract] Income [Abstract] Shares [Abstract] Shares [Abstract] Net earnings, basic (in shares) Weighted Average Number of Shares Outstanding, Basic Dilutive effect of employee stock options and awards, (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Per Share Amount [Abstract] Per Share Amount [Abstract] Net Income (Loss) Available to Common Stockholders, Diluted Net Income (Loss) Available to Common Stockholders, Diluted Weighted Average Number of Shares Outstanding, Diluted Weighted Average Number of Shares Outstanding, Diluted Revenue from Contract with Customer [Abstract] Notes Receivable [Member] Notes Receivable [Member] Unbilled Contracts Receivable [Member] Unbilled Contracts Receivable [Member] Unbilled Contracts Receivable [Member] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Domain] Contract with Customer, Basis of Pricing [Domain] Contract with Customer, Duration [Axis] Contract with Customer, Duration [Axis] Contract with Customer, Duration [Domain] Contract with Customer, Duration [Domain] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Domain] Timing of Transfer of Good or Service [Domain] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Unbilled Services, Allowance for Credit Loss Unbilled Services, Allowance for Credit Loss Unbilled Services, Allowance for Credit Loss Note Receivable, Allowance for Credit Loss Note Receivable, Allowance for Credit Loss Note Receivable, Allowance for Credit Loss Allowance for Credit Loss Allowance for Credit Loss Allowance for Credit Loss Current Expected Credit Losses Opening Balance Sheet Impact on Retained Earnings Current Expected Credit Losses Opening Balance Sheet Impact on Retained Earnings Current Expected Credit Losses Opening Balance Sheet Impact on Retained Earnings Accounts Receivable, Credit Loss Expense (Reversal) Accounts Receivable, Credit Loss Expense (Reversal) Unbilled Services, Credit Loss Expense (Reversal) Unbilled Services, Credit Loss Expense (Reversal) Unbilled Services, Credit Loss Expense (Reversal) Note Receivable, Credit Loss Expense (Reversal) Note Receivable, Credit Loss Expense (Reversal) Note Receivable, Credit Loss Expense (Reversal) Credit Loss Expense (Reversal) Credit Loss Expense (Reversal) Credit Loss Expense (Reversal) Allowance for Credit Loss, Write Off Allowance for Credit Loss, Write Off Allowance for Credit Loss, Write Off Increase Decrease in Operating Income Loss Increase Decrease in Operating Income Loss Increase (decrease) in operating profit due to favorable/unfavorable pricing adjustments Sales Commission Amortization Period Minimum Sales Commission Amortization Period Minimum Sales Commission Amortization Period Minimum Contract with Customer, Asset, before Allowance for Credit Loss Contract with Customer, Asset, before Allowance for Credit Loss Percent of remaining performance obligations recognized as revenue in next year Percent of remaining performance obligations recognized as revenue in next year Percent of remaining performance obligations recognized as revenue in next year Long Term Contracts Duration Minimum Long Term Contracts Duration Minimum Long Term Contracts Duration Minimum Long Term Contracts Duration Maximum Long Term Contracts Duration Maximum Long Term Contracts Duration Maximum Accrued Sales Commission Accrued Sales Commission Capitalized Contract Cost, Net Capitalized Contract Cost, Net Amount of Deferred Costs Related to Long-term Contracts Sales Commission Amortization Period Maximum Sales Commission Amortization Period Maximum Sales Commission Amortization Period Maximum Capitalized Contract Cost, Amortization Period Capitalized Contract Cost, Amortization Period Short term debt issuance costs Short term debt issuance costs Short term debt issuance costs Long term debt issuance costs Long term debt issuance costs Long term debt issuance costs 4.625% Senior notes due 2020 4.625% Senior notes due 2020 4.625% Senior notes due 2020 2.30% senior notes due 2024 2.30% senior notes due 2024 2.30% senior notes due 2024 2.95% senior notes due 2029 2.95% senior notes due 2029 2.95% senior notes due 2029 Restructuring Cost and Reserve [Axis] Employee Severance [Member] Facility Closing [Member] Restructuring Reserve Restructuring Charges Restructuring Reserve Settled With Cash And Other Adjustment Net restructuring charges Net Restructuring Charges Amount charged against earnings in the period for incurred and estimated costs, excluding asset retirement obligations, associated with exit from or disposal of business activities or restructurings pursuant to a program that is planned and controlled by management, and changes either scope of business by an entity, or manner business is conducted. May include amount of reversals and other adjustments during the period to amounts of previously accrued liabilities for specified types of restructuring costs. Restructuring charges related to severance and other employee costs Severance Costs Other Asset Impairment Charges Other Asset Impairment Charges Restructuring charges related to contractual obligations associated with leased facilities and other facility related costs Business Exit Costs Employee Severance Benefits Related Restructuring Reserve Accrual Adjustment Asset Impairment Charges Restructuring Impairment Restructuring Impairment Operating Lease, Impairment Loss Operating Lease, Impairment Loss Unused facility restructuring reserves Reduction in total prior restructuring accruals Restructuring Reserve, Current Restructuring Reserve, Noncurrent Schedule of Goodwill [Table] Schedule of Goodwill [Table] Goodwill [Line Items] Goodwill [Line Items] Severance Costs Balance as of January 1 Adjustments to goodwill Goodwill, Translation and Purchase Accounting Adjustments Balance at end of period Finite-Lived Intangible Assets, Accumulated Amortization Percentage Fair Value of Goodwill Exceeded Carrying Value Percentage Fair Value of Goodwill Exceeded Carrying Value Percentage Fair Value of Goodwill Exceeded Carrying Value Percentage Change in Discount Rate Used to Calculate Fair Value of Goodwill Percentage Change in Discount Rate Used to Calculate Fair Value of Goodwill Percentage Change in Discount Rate Used to Calculate Fair Value of Goodwill Value of Goodwill Impairment Following a Percentage Change in the Discount Rate Used to Calculate Goodwill for Reporting Unit Value of Goodwill Impairment Following a Percentage Change in the Discount Rate Used to Calculate Goodwill for Reporting Unit Value of Goodwill Impairment Following a Percentage Change in the Discount Rate Used to Calculate Goodwill for Reporting Unit Percent Change in Discount Rate Used to Calculate Fair Value of Goodwill for Reporting Unit Percent Change in Discount Rate Used to Calculate Fair Value of Goodwill for Reporting Unit Percent Change in Discount Rate Used to Calculate Fair Value of Goodwill for Reporting Unit Percent of Fair Value Exceeding Carrying Value Post Percent Change in Discount Rate Used to Calculate Fair Value of Goodwill for Reporting Unit Percent of Fair Value Exceeding Carrying Value Post Percent Change in Discount Rate Used to Calculate Fair Value of Goodwill for Reporting Unit Percent of Fair Value Exceeding Carrying Value Post Percent Change in Discount Rate Used to Calculate Fair Value of Goodwill for Reporting Unit Value of Reporting Unit's Goodwill Following Impairment Value of Reporting Unit's Goodwill Following Impairment Value of Reporting Unit's Goodwill Following Impairment Value of Reporting Units Goodwill Fair Value Exceeds Carrying Value Value of Reporting Units Goodwill Fair Value Exceeds Carrying Value Value of Reporting Units Goodwill Fair Value Exceeds Carrying Value Goodwill [Roll Forward] Goodwill [Roll Forward]