Laboratory Corporation of America (LH) 10-K 26 Feb 24 2023 FY Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($) shares in Millions, $ in Billions	12 Months Ended
	Dec. 31, 2023	Feb. 23, 2024	Jun. 30, 2023
Document Information [Line Items]
Auditor Firm ID	34
Auditor Location	Raleigh, North Carolina
Auditor Name	Deloitte & Touche LLP
ICFR Auditor Attestation Flag	true
Entity Voluntary Filers	No
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	1-11353
Entity Registrant Name	LABORATORY CORPORATION OF AMERICA HOLDINGS
Entity Central Index Key	0000920148
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
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 Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 17.3
Entity Common Stock, Shares Outstanding		84.1
Documents Incorporated by Reference	List hereunder the following documents if incorporated by reference and the Part of the Form 10-K into which the document is incorporated: Portions of the Registrant’s Notice of Annual Meeting and Proxy Statement to be filed no later than 120 days following December 31, 2023, are incorporated by reference into Part III.

Cover

Cover	12 Months Ended
	Dec. 31, 2023
Cover [Abstract]
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false

OTHER LIABILITIES

OTHER LIABILITIES	12 Months Ended
	Dec. 31, 2023
Other Liabilities Disclosure [Abstract]
OTHER LIABILITIES	OTHER LIABILITIES December 31, 2023 December 31, 2022 Deferred compensation plan obligation $ 107.4 $ 96.9 Defined-benefit plan obligation 64.5 50.8 Worker's compensation and auto 41.4 46.4 Cross currency swaps liability 53.7 45.7 Other 142.3 161.3 $ 409.3 $ 401.1

OTHER LIABILITIES_2

OTHER LIABILITIES	12 Months Ended
	Dec. 31, 2023
Other Liabilities Disclosure [Abstract]
Other liabilities	December 31, 2023 December 31, 2022 Deferred compensation plan obligation $ 107.4 $ 96.9 Defined-benefit plan obligation 64.5 50.8 Worker's compensation and auto 41.4 46.4 Cross currency swaps liability 53.7 45.7 Other 142.3 161.3 $ 409.3 $ 401.1

OTHER LIABILITIES_2_3

OTHER LIABILITIES - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Other Liabilities Disclosure [Abstract]
Deferred Compensation Liability, Classified, Noncurrent	$ 107.4	$ 96.9
Other liabilities	409.3	401.1
Defined-benefit plan obligation	64.5	50.8
Workers' Compensation Liability, Noncurrent	41.4	46.4
Foreign Currency Contracts, Liability, Fair Value Disclosure	53.7	45.7
Other	$ 142.3	$ 161.3

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Deferred Revenue, Revenue Recognized	$ 78,900,000	$ 99,700,000
Current assets:
Cash and Cash Equivalents, at Carrying Value	536,800,000	320,600,000
Accounts receivable, net	1,913,300,000	1,785,500,000
Unbilled Contracts Receivable	185,400,000	211,800,000
Supplies inventory	474,600,000	470,600,000
Prepaid expenses and other	655,300,000	610,400,000
Disposal Group, Including Discontinued Operation, Assets, Current	0	1,226,100,000
Total current assets	3,765,400,000	4,625,000,000
Property, plant and equipment, net	2,911,800,000	2,794,100,000
Goodwill, net	6,142,500,000	6,123,700,000
Intangible assets, net	3,342,000,000	3,123,600,000
Joint venture partnerships and equity method investments	26,900,000	65,700,000
Deferred Income Tax Assets, Net	0	6,400,000
Other assets, net	536,500,000	378,400,000
Disposal Group, Including Discontinued Operation, Assets, Noncurrent	0	3,038,200,000
Total assets	16,725,100,000	20,155,100,000
Current liabilities:
Finance Lease, Liability, Current	6,400,000	6,000,000
Accounts payable	827,500,000	852,200,000
Accrued expenses and other	804,000,000	787,000,000
Deferred Revenue, Current	421,700,000	310,600,000
Operating Lease, Liability, Current	165,800,000	163,800,000
Short-term borrowings and current portion of long-term debt	999,800,000	301,300,000
Disposal Group, Including Discontinued Operation, Liabilities, Current	0	657,600,000
Total current liabilities	3,225,200,000	3,078,500,000
Long-term debt, less current portion	4,054,700,000	5,038,800,000
Total maturities, due beyond one year	648,900,000	652,900,000
Total maturities, due beyond one year	78,600,000	83,600,000
Deferred income taxes and other tax liabilities	417,900,000	543,400,000
Other liabilities	409,300,000	401,100,000
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent	0	241,300,000
Total liabilities	8,834,600,000	10,039,600,000
Commitments and contingent liabilities
Noncontrolling interest	15,500,000	18,900,000
Shareholders’ equity
Common stock, 83.9 and 88.2 shares outstanding at December 31, 2023 and 2022, respectively	7,700,000	8,100,000
Additional paid-in capital	38,400,000	0
Retained earnings	7,888,200,000	10,581,700,000
Accumulated other comprehensive loss	(59,300,000)	(493,200,000)
Total shareholders’ equity	7,875,000,000	10,096,600,000
Total liabilities and shareholders’ equity	$ 16,725,100,000	20,155,100,000
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents		109,400,000
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net		436,500,000
Disposal Group, Including Discontinued Operation, Other Assets, Current		583,600,000
Disposal Group, Including Discontinued Operation, Prepaid and Other Assets, Current		96,600,000
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Noncurrent		162,100,000
Disposal Group, Including Discontinued Operation, Goodwill, Noncurrent		1,997,300,000
Disposal Group, Including Discontinued Operation, Intangible Assets, Noncurrent		823,300,000
Disposal Group, Including Discontinued Operation, Deferred Tax Assets		1,200,000
Disposal Group, Including Discontinued Operation, Other Assets, Noncurrent		54,300,000
Disposal Group, Including Discontinued Operation, Assets		4,264,300,000
Disposal Group, Including Discontinued Operation, Accounts Payable, Current		82,600,000
Disposal Group, Including Discontinued Operation, Accrued Liabilities, Current		281,800,000
Disposal Group, Including Discontinued Operation, Deferred Revenue, Current		271,500,000
Disposal Group, Including Discontinued Operation, Short-term operating lease liabilities		21,700,000
Disposal Group, Including Discontinued Operation, Operating lease liabilities		26,800,000
Disposal Group, Including Discontinued Operation, Accrued Income Tax Payable, Noncurrent		192,800,000
Disposal Group, Including Discontinued Operation, Other Liabilities, Noncurrent		21,700,000
Disposal Group, Including Discontinued Operation, Liabilities		$ 898,900,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Consolidated Statements of Operations [Abstract]
Revenues	$ 12,161.6	$ 11,863.9	$ 13,136.1
Cost of Revenue	8,796.7	8,155	8,143.7
Gross profit	3,364.9	3,708.9	4,992.4
Selling, general and administrative expenses	2,021.4	1,763.1	1,690.3
Amortization of intangibles and other assets	219.8	193.6	229.5
Goodwill and Intangible Asset Impairment	349	261.7	0
Restructuring and other special charges	49.1	54	24
Operating income	725.6	1,436.5	3,048.6
Interest expense	(199.6)	(179.8)	(211.8)
Equity method income, net	(1.4)	5.4	26.5
Investment income	28.8	7.5	8.8
Other, net	15.5	(32.2)	15.5
Provision for income taxes	188.5	233.9	690
Net earnings	419.2	1,280.6	2,379.5
Less: Net earnings attributable to the noncontrolling interest	(1.2)	(1.5)	(2.2)
Net earnings attributable to Laboratory Corporation of America Holdings	$ 418	$ 1,279.1	$ 2,377.3
Income (Loss) from Continuing Operations, Per Basic Share	$ 4.35	$ 11	$ 22.71
Earnings Per Share, Basic	$ 4.80	$ 14.05	$ 24.60
Income (Loss) from Continuing Operations Before Income Taxes and Noncontrolling Interest	$ 568.9	$ 1,237.4	$ 2,887.6
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	380.4	1,003.5	2,197.6
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 38.8	$ 277.1	$ 181.9
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	$ 0.45	$ 3.04	$ 1.88
Income (Loss) from Continuing Operations, Per Diluted Share	4.33	10.94	22.52
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share	0.44	3.03	1.87
Earnings Per Share, Diluted	$ 4.77	$ 13.97	$ 24.39

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net earnings	$ 419.2	$ 1,280.6	$ 2,379.5
Foreign currency translation adjustments	183.1	(336.4)	(104.6)
Net benefit plan adjustments	14.6	44.8	91.7
Other comprehensive earnings (loss) before tax	197.7	(291.6)	(12.9)
Provision for income tax related to items of comprehensive earnings	(1.8)	(9.7)	(17.1)
Other comprehensive earnings (loss), net of tax	195.9	(301.3)	(30)
Comprehensive earnings	615.1	979.3	2,349.5
Less: Net earnings attributable to the noncontrolling interest	(1.2)	(1.5)	(2.2)
Comprehensive earnings attributable to Laboratory Corporation of America Holdings	613.9	977.8	2,347.3
Stockholders' Equity Note, Spinoff Transaction	(1,732)
AOCI Attributable to Parent [Member]
Other comprehensive earnings (loss), net of tax	195.9	$ (301.3)	$ (30)
Stockholders' Equity Note, Spinoff Transaction	238
Foreign Currency Translation Adjustments
Stockholders' Equity Note, Spinoff Transaction	231.6
Net Benefit Plan Adjustments
Stockholders' Equity Note, Spinoff Transaction	$ 6.4

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Earnings (Loss)
Common Stock, Value, Outstanding	$ 9
Additional Paid in Capital	110.3
Retained Earnings (Accumulated Deficit)	9,479.2
Accumulated Other Comprehensive Income (Loss), Net of Tax	(161.9)
BALANCE at Dec. 31, 2020	9,436.6
Net earnings attributable to Laboratory Corporation of America Holdings	2,377.3	$ 0	$ 0	$ 2,377.3	$ 0
Other comprehensive earnings (loss), net of tax	(30)	0	0	0	(30)
Issuance of common stock under employee stock plans	51.7	0	51.7	0	0
Net share settlement tax payments from issuance of stock to employees	(47.4)	0	(47.4)	0	0
Stock compensation	153.7	0	153.7	0	0
Purchase of common stock	(1,668.5)	(0.5)	(268.3)	(1,399.7)	0
BALANCE at Dec. 31, 2021	10,273.4
Common Stock, Value, Outstanding		8.5
Additional Paid in Capital			0
Retained Earnings (Accumulated Deficit)				10,456.8
Accumulated Other Comprehensive Income (Loss), Net of Tax					(191.9)
Net earnings attributable to Laboratory Corporation of America Holdings	1,279.1	0	0	1,279.1	0
Other comprehensive earnings (loss), net of tax	(301.3)	0	0	0	(301.3)
Issuance of common stock under employee stock plans	50.6	0	50.6	0	0
Net share settlement tax payments from issuance of stock to employees	(50.6)	0	(50.6)	0	0
Stock compensation	144.1	0	144.1	0	0
Purchase of common stock	(1,100)	(0.4)	(144.1)	(955.5)	0
BALANCE at Dec. 31, 2022	10,096.6
Dividends		0	0	(198.7)	0
Dividends, Cash	(198.7)
Common Stock, Value, Outstanding	8.1	8.1
Additional Paid in Capital	0		0
Retained Earnings (Accumulated Deficit)	10,581.7			10,581.7
Accumulated Other Comprehensive Income (Loss), Net of Tax	(493.2)				(493.2)
Net earnings attributable to Laboratory Corporation of America Holdings	418	0	0	418	0
Other comprehensive earnings (loss), net of tax	195.9	0	0	0	195.9
Issuance of common stock under employee stock plans	55.2	0	55.2	0	0
Net share settlement tax payments from issuance of stock to employees	(40.9)	0	(40.9)	0	0
Stock compensation	147.3	0	147.3	0	0
Purchase of common stock	(1,009)	(0.4)	(123.2)	(885.4)	0
BALANCE at Dec. 31, 2023	7,875
Dividends		0	0	(256.1)	0
Dividends, Cash	(256.1)
Stockholders' Equity Note, Spinoff Transaction	(1,732)	0	0	(1,970)	238
Common Stock, Value, Outstanding	7.7	$ 7.7
Additional Paid in Capital	38.4		$ 38.4
Retained Earnings (Accumulated Deficit)	7,888.2			$ 7,888.2
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (59.3)				$ (59.3)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net earnings	$ 419.2	$ 1,280.6	$ 2,379.5
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	577.3	537.2	577
Stock compensation	128.7	116.8	132.9
Depreciation And Amortization Of Leased Assets	168	172.5	164
Goodwill and Intangible Asset Impairment	349	261.7	0
Increase (Decrease) in Deferred Liabilities	(78.1)	26.3	(37.3)
Other Operating Activities, Cash Flow Statement	38.9	23	(34.1)
Change in assets and liabilities (net of effects of acquisitions and divestitures):
(Increase) decrease in accounts receivable	(103.8)	46.5	267.4
Increase (Decrease) in Contract with Customer, Asset	28.5	(23.4)	(41.1)
Increase (Decrease) in Inventories	(0.7)	(45.5)	2.8
Increase in prepaid expenses and other	(25.8)	(244.1)	(41.5)
Increase (Decrease) in Accounts Payable	(42.4)	285.4	(5.3)
Increase (Decrease) in Deferred Revenue	105.5	67.8	3.8
Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities	(323.2)	(462.9)	(339.9)
Net cash provided by operating activities	1,327.7	1,955.9	3,109.6
CASH FLOWS FROM INVESTING ACTIVITIES:
Payments to Acquire Property, Plant, and Equipment	(453.6)	(429.3)	(421.5)
Payments to Acquire Equity Method Investments	(29)	(17.4)	(27.8)
Proceeds from sale of assets	0.6	1.4	87.3
Proceeds from Sale of Other Investments	6.7	5.2	13.2
Proceeds from Divestiture of Businesses	0	2.9	0
Proceeds from Derivative Instrument, Investing Activities	0	1.6	0
Payments to Acquire Businesses, Net of Cash Acquired	(671.5)	(1,164)	(496.9)
Net Cash Provided by (Used in) Investing Activities, Total	(1,171.5)	(1,652.2)	(884.6)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from senior note offerings	0	0	1,000
Repayments of Senior Debt	(300)	0	(1,000)
Repayments of Other Long-term Debt	0	0	(375)
Payments on revolving credit facilities	2,488.2	787.4	0
Repayments of Lines of Credit	(2,488.2)	(787.4)	0
Share-based Payment Arrangement, Exercise of Option, Tax Benefit	(39.8)	(50.6)	(47.5)
Net proceeds from issuance of stock to employees	54.4	50.6	51.7
Payments of Ordinary Dividends	(254)	(195.2)	0
Payments for Repurchase of Common Stock	(1,000)	(1,100)	(1,668.5)
Proceeds from (Payments for) Other Financing Activities	(19.6)	(27)	(26.5)
Effect of exchange rate changes on cash and cash equivalents	(59.3)	(1,322.2)	(2,065.8)
Effect of exchange rate changes on cash and cash equivalents	9.9	(24.2)	(7.3)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	106.8	(1,042.7)	151.9
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations		430	1,472.7
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents			1,381.4
Cash and cash equivalents	536.8	320.6
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(38.8)	(277.1)	(181.9)
Continuing Operations
Change in assets and liabilities (net of effects of acquisitions and divestitures):
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	1,202.3	1,764.8	2,846.3
CASH FLOWS FROM INVESTING ACTIVITIES:
Net Cash Provided by (Used in) Investing Activities, Continuing Operations	(1,146.8)	(1,599.6)	(845.7)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net Cash Provided by (Used in) Financing Activities, Continuing Operations	(1,559)	(1,322.2)	(2,065.8)
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Disposal Group, Including Discontinued Operations	0	109.4	91.3
Discontinued Operations
Change in assets and liabilities (net of effects of acquisitions and divestitures):
Cash Provided by (Used in) Operating Activities, Discontinued Operations	125.4	191.1	263.3
CASH FLOWS FROM INVESTING ACTIVITIES:
Cash Provided by (Used in) Investing Activities, Discontinued Operations	(24.7)	(52.6)	(38.9)
CASH FLOWS FROM FINANCING ACTIVITIES:
Cash Provided by (Used in) Financing Activities, Discontinued Operations	$ 1,499.7	$ 0	$ 0

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING - EARNINGS PER SHARE - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income [Abstract]
Net earnings, basic	$ 418	$ 1,279.1	$ 2,377.3
Net earnings, diluted	$ 418	$ 1,279.1	$ 2,377.3
Shares [Abstract]
Outstanding shares, diluted (in shares)	87.6	91.6	97.5
Outstanding shares, basic (in shares)	87.1	91.1	96.7
Dilutive effect of stock options (in shares)	0.5	0.5	0.8
Per Share Amount [Abstract]
Earnings Per Share, Basic	$ 4.80	$ 14.05	$ 24.60
Diluted earnings per share (in dollars per share)	$ 4.77	$ 13.97	$ 24.39

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING - PROPERTY, PLANT AND EQUIPMENT	12 Months Ended
	Dec. 31, 2023 yr
Property, Plant and Equipment [Line Items]
Property plant and equipment useful life software minimum	3
Property plant and equipment useful life software maximum	15
Estimated useful life of capitalized software costs (in years)	5
Minimum [Member] | Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (years)	3 years
Minimum [Member] | Buildings and building improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (years)	10 years
Minimum [Member] | Software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (years)	3 years
Minimum [Member] | Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (years)	5 years
Maximum [Member] | Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (years)	10 years
Maximum [Member] | Buildings and building improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (years)	55 years
Maximum [Member] | Software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (years)	10 years
Maximum [Member] | Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (years)	10 years

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING - INTANGIBLE ASSETS - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 6,142,500,000	$ 6,123,700,000	$ 5,891,000,000
Minimum [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of finite-lived intangible assets, minimum (years)	10 years
Minimum [Member] | Patents, Licenses And Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of finite-lived intangible assets, minimum (years)	3 years
Minimum [Member] | Non-compete agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of finite-lived intangible assets, minimum (years)	3 years
Minimum [Member] | Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of finite-lived intangible assets, minimum (years)	1 year
Maximum [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of finite-lived intangible assets, minimum (years)	36 years
Maximum [Member] | Patents, Licenses And Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of finite-lived intangible assets, minimum (years)	15 years
Maximum [Member] | Non-compete agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of finite-lived intangible assets, minimum (years)	5 years
Maximum [Member] | Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of finite-lived intangible assets, minimum (years)	15 years

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Financial Statement Presentation Laboratory Corporation of America ® Holdings (Labcorp or the Company) (Labcorp or the Company) is a global leader of innovative and comprehensive laboratory services that provides vital information to help doctors, hospitals, pharmaceutical 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. With more than 67,000 employees, the Company serves clients in more than 100 countries. The Company reports its business in two segments, Labcorp Diagnostics (Dx) and Biopharma Laboratory Services (BLS), formerly Drug Development (DD). For further financial information about these segments, including information for each of the last three fiscal years regarding revenue, operating income, and other important information, see Note 20 Business Segment Information. In 2023, Dx and BLS contributed 77% and 23%, respectively, of revenues to the Company, and in 2022 contributed 77% and 23%, respectively. The consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries for which it exercises control. Long-term investments in affiliated companies in which the Company exercises significant influence, but which it does not control, are accounted for using the equity method. Investments in which the Company does not exercise significant influence (generally, when the Company has an investment of less than 20% and no representation on the investee's board of directors) are accounted for 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 variable interest entities or special purpose entities whose financial results are not included in the consolidated financial statements. The financial statements of the Company's 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 year. Resulting translation adjustments are included in “Accumulated other comprehensive income.” On June 30, 2023, the Company completed the separation (spin-off) of Fortrea Holdings Inc. (Fortrea), formerly the Company’s Clinical Development and Commercialization Services (CDCS) business, into a separate, publicly-traded company. All current and historical operating results of Fortrea are presented as Discontinued Operations, net of tax, in the consolidated statement of operations. As a result of the spin-off the Company recast segment results to exclude the historical results of the CDCS business for all periods presented. The remaining operations of the previously reported Drug Development segment has been renamed the Biopharma Laboratory Services segment. Additional disclosures regarding the spin-off of Fortrea are provided in Note 2 (Discontinued Operations). Reimbursable Out-of-Pocket Expenses BLS pays on behalf of its customers certain out-of-pocket costs for which the Company is reimbursed at cost, without mark-up or profit. Out-of-pocket costs paid by BLS are reflected in cost of revenues, while the reimbursements received are reflected in revenues in the consolidated statements of operations. Cost of Revenues Cost of revenue includes direct labor and related benefit charges, reimbursable expenses, other direct costs, shipping and handling fees, and an allocation of facility charges and information technology costs. Selling, General and Administrative Expenses Selling, general and administrative expenses consist primarily of administrative payroll and related benefit charges, advertising and promotional expenses, administrative travel and an allocation of facility charges and information technology costs. Cost of advertising is expensed as incurred. Research and Development The Company expenses R&D costs as incurred. Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reported periods. Significant estimates include implicit price concessions, revenue estimates, the allowances for doubtful accounts, deferred tax assets, fair values of acquired assets and assumed liabilities in business combinations, fair value of goodwill and indefinite-lived intangible assets, amortization lives for acquired intangible assets, and accruals for self-insurance reserves, litigation reserves and pensions. Actual results could differ from those estimates. The extent to which the COVID-19 pandemic has and will continue to impact the Company’s business and financial results depend on numerous evolving factors including, but not limited to the magnitude and duration of the COVID-19 pandemic, the impact to worldwide macroeconomic conditions including interest rates, employment rates and health insurance coverage, the speed of the anticipated recovery, and governmental and business reactions to the pandemic. The Company assessed certain accounting matters that generally require consideration of forecasted financial information in context with the information reasonably available to the Company and the unknown future impacts of COVID-19 as of December 31, 2023, and through the date of this Annual Report. The accounting matters assessed included, but were not limited to, the Company’s implicit price concessions and credit losses, equity investments, and the carrying value of goodwill and other long-lived assets. The Company’s future assessment of the magnitude and duration of the COVID-19 pandemic, as well as other factors, could impact the Company’s consolidated financial statements in future reporting periods. Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. The Company maintains cash and cash equivalents with various major financial institutions. The total cash and cash equivalent balances that exceeded the balances insured by the Federal Deposit Insurance Commission, were approximately $534.7 and $428.1 at December 31, 2023, and 2022, respectively. Substantially all of the Company’s accounts receivable are with companies in the healthcare or pharmaceutical industry and individuals. However, concentrations of credit risk are mitigated due to the number of the Company’s customers as well as their dispersion across many different geographic regions. Although Dx has receivables due from U.S. and state governmental agencies, the Company does not believe that such receivables represent a credit risk since the related healthcare programs are funded by U.S. and state governments, and payment is primarily dependent upon submitting appropriate documentation. Accounts receivable balances (gross) from Medicare and Medicaid were $86.5 and $85.8 at December 31, 2023, and 2022, respectively. For the Company's operations in Ontario, Canada, the Ontario Ministry of Health and Long-Term Care (Ministry) determines who can establish a licensed community medical laboratory and caps the amount that each of these licensed laboratories can bill the government sponsored healthcare plan. The Ontario government-sponsored healthcare plan covers the cost of commercial laboratory testing performed by the licensed laboratories. The provincial government discounts the annual testing volumes based on certain utilization discounts and establishes an annual maximum it will pay for all community laboratory tests. The agreed-upon reimbursement rates are subject to Ministry review at the end of year and can be adjusted (at the government's discretion) based upon the actual volume and mix of test work performed by the licensed healthcare providers in the province during the year. The capitated accounts receivable balance from the Ontario government sponsored healthcare plan was CAD 5.5 at December 31, 2023. There were no capitated accounts receivables from the Ontario government sponsored healthcare plan at December 31, 2022. The portion of the Company's accounts receivable due from patients comprises the largest portion of credit risk. At December 31, 2023, and 2022, receivables due from patients represented approximately 20.4% and 15.3% of the Company's consolidated gross accounts receivable, respectively. The Company applies assumptions and judgments including historical collection experience and reasonable and supportable forecasts for assessing collectability and determining allowances for doubtful accounts for accounts receivable from patients. Earnings per Share Basic earnings per share is computed by dividing net earnings attributable to Laboratory Corporation of America Holdings by the weighted average number of common shares outstanding. Diluted earnings per share is computed by dividing net earnings including the impact of dilutive adjustments by the weighted average number of common shares outstanding plus potentially dilutive shares, as if they had been issued at the earlier of the date of issuance or the beginning of the period presented. Potentially dilutive common shares result primarily from the Company’s outstanding stock options, restricted stock awards, performance share awards, and accelerated share repurchases. The following represents a reconciliation of basic earnings per share to diluted earnings per share: 2023 2022 2021 Income Shares Per Share Income Shares Per Share Income Shares Per Share Basic earnings per share $ 418.0 87.1 $ 4.80 $ 1,279.1 91.1 $ 14.05 $ 2,377.3 96.7 $ 24.60 Stock options and stock awards — 0.5 — 0.5 — 0.8 Diluted earnings per share $ 418.0 87.6 $ 4.77 $ 1,279.1 91.6 $ 13.97 $ 2,377.3 97.5 $ 24.39 The following table summarizes the potential common shares not included in the computation of diluted earnings per share because their impact would have been antidilutive: Years Ended December 31, 2023 2022 2021 Stock options 0.2 0.2 0.1 Stock Compensation Plans The Company measures stock compensation cost for all equity awards at fair value on the date of grant and recognizes compensation expense over the service period for awards expected to vest. The fair value of restricted stock units is determined based on the number of shares granted and the quoted price of the Company’s Common Stock on the grant date. The grant date fair value of performance awards is based on a Monte Carlo simulated fair value for the relative (as compared to the peer companies) total shareholder return component of the performance awards. Such value is recognized as an expense over the service period, net of estimated forfeitures and the Company's determination of whether it is probable that the performance targets will be achieved. At the end of each reporting period, the Company reassesses the probability of achieving performance targets. The estimation of equity awards that will ultimately vest requires judgment, and the Company considers many factors when estimating expected forfeitures, including types of awards, employee class, and historical experience. Forfeitures are recognized as a reduction of compensation expense in earnings in the period in which they occur. See Note 14 Stock Compensation Plans for assumptions used in calculating compensation expense for the Company’s stock compensation plans. Cash Equivalents Cash and cash equivalents consist of highly liquid instruments, such as commercial paper, time deposits, and other money market instruments, which have maturities when purchased of three months or less. Supplies Inventory Inventories, consisting primarily of purchased laboratory and customer supplies and finished goods, are stated at the lower of cost (first-in, first-out) or net realizable value. Supplies accounted for $385.1 and $412.8 and finished goods accounted for $89.5 and $57.8 of total inventory at December 31, 2023, and 2022, respectively. The Company's inventory reserve balance was $66.1 and $23.3, as of December 31, 2023 and 2022, respectively. Property, Plant and Equipment Property, plant and equipment are recorded at cost. Depreciation and amortization expense is computed on all classes of assets based on their estimated useful lives, as indicated below, using the straight-line method. Years Buildings and building improvements 10 - 55 Machinery and equipment 3 - 10 Furniture and fixtures 5 - 10 Software 3 - 10 Leasehold improvements are amortized over the shorter of their estimated useful lives or the term of the related leases. Expenditures for repairs and maintenance are charged to operations as incurred. Retirements, sales and other disposals of assets are recorded by removing the cost and accumulated depreciation from the related accounts with any resulting gain or loss reflected in the consolidated statements of operations. Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amounts may not be recoverable. If the carrying value is no longer recoverable based upon the undiscounted future cash flows of the asset, the amount of the impairment is the difference between the carrying amount and the fair value of the asset. Capitalized Software Costs The Company capitalizes purchased software that is ready for service and capitalizes software development costs incurred on significant projects starting from the time that the preliminary project stage is completed and the Company commits to funding a project until the project is substantially complete and the software is ready for its intended use. Capitalized costs include direct material and service costs and payroll and payroll-related costs. Research and development (R&D) costs and other computer software maintenance costs related to software development are expensed as incurred. Capitalized software costs are amortized using the straight-line method over the estimated useful life of the underlying system ranging from three to fifteen years, generally five years. Amortization begins once the underlying system is substantially complete and ready for its intended use. Goodwill and Indefinite-lived Intangibles The Company assesses goodwill and indefinite-lived intangibles, which are not amortized, 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 annual impairment test for goodwill includes an option to perform a qualitative assessment of whether it is more likely than not that a reporting unit's fair value is less than its carrying value. Reporting units are businesses with discrete financial information that is available and reviewed by management. If the Company determines that it is more likely than not that the fair value of a reporting unit is less than its carrying value, then the Company performs the quantitative goodwill impairment test. The Company may also choose to bypass the qualitative assessment for any reporting unit in its goodwill assessment and proceed directly to performing the quantitative assessment. The Company recognizes an impairment charge for the amount by which the reporting unit's carrying amount exceeds its fair value. In the qualitative assessment, the Company considers relevant events and circumstances for each reporting unit, including (i) current year results, (ii) financial performance versus management’s annual and five-year strategic plans, (iii) changes in the reporting unit carrying value since prior year, (iv) industry and market conditions in which the reporting unit operates, (v) macroeconomic conditions, including discount rate changes, and (vi) changes in products or services offered by the reporting unit. If applicable, performance in recent years is compared to forecasts included in prior quantitative valuations. Based on the results of the qualitative assessment, if the Company concludes that it is not more likely than not that the fair value of the reporting unit is less than its carrying values of the reporting unit, then no quantitative assessment is performed. The quantitative assessment includes the estimation of the fair value of each reporting unit as compared to the carrying value of the reporting unit. The Company estimates the fair value of a reporting unit using both income-based and market-based valuation methods. The income-based approach is based on the reporting unit's forecasted future cash flows that are discounted to the present value using the reporting unit's weighted average cost of capital. For the market-based approach, the Company utilizes a number of factors such as publicly available information regarding the market capitalization of the Company as well as operating results, business plans, market multiples, and present value techniques. Based upon the range of estimated values developed from the income and market-based methods, the Company determines the estimated fair value for the reporting unit. If the estimated fair value of the reporting unit exceeds the carrying value, the goodwill is not impaired and no further review is required. Management performed its annual goodwill and intangible asset impairment testing as of the beginning of the fourth quarter of 2023. The Company elected to perform the qualitative assessment for goodwill and intangible assets for the domestic Dx reporting unit and the Clinical Trials Testing Solutions (CTTS) reporting unit, and a quantitative assessment for the Early Development (ED) reporting unit, and the Canadian reporting unit which includes indefinite-lived assets consisting of acquired Canadian licenses. Based upon the results of the qualitative and quantitative assessments, the Company concluded that the fair values of its domestic Dx, CTTS and Canadian reporting units, as of October 1, 2023, were greater than the carrying values. However, due to lower demand in the ED reporting unit in late 2023, which the Company anticipates will continue into early 2024 there is an expectation of lower near term revenue and profitability. Therefore, the Company concluded that the fair value of the ED reporting unit was less than carrying value and recorded a goodwill impairment of $333.6 in the BLS segment. Although the Company believes that the current assumptions and estimates used in its goodwill analysis are reasonable, supportable, and appropriate, continued efforts to maintain or improve the performance of these businesses could be impacted by unfavorable or unforeseen changes which could impact the existing assumptions used in the impairment analysis. Various factors could reasonably be expected to unfavorably impact existing assumptions: primarily delays in new customer bookings and the related delay 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. It is possible that the Company's conclusions regarding impairment or recoverability of goodwill or intangible assets in any reporting unit could change in future periods. There can be no assurance that the estimates and assumptions used in the Company's goodwill and intangible asset impairment testing performed as of the beginning of the fourth quarter of 2023 will prove to be accurate predictions of the future, if, for example, (i) the businesses do not perform as projected, (ii) overall economic conditions in 2024 or future years vary from current assumptions (including changes in discount rates), (iii) business conditions or strategies for a specific reporting unit change from current assumptions, including loss of major customers, (iv) investors require higher rates of return on equity investments in the marketplace or (v) enterprise values of comparable publicly traded companies, or actual sales transactions of comparable companies, were to decline, resulting in lower multiples of revenues and EBITDA. Intangible Assets Intangible assets with finite lives are amortized on a straight-line basis over the expected periods to be benefited, as set forth in the table below, such as legal life for patents and technology and contractual lives for non-compete agreements. Years Customer relationships 10 - 36 Patents, licenses and technology 3 - 15 Non-compete agreements 3 - 5 Trade names 1 - 15 Intangible assets with finite lives are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amounts may not be recoverable. If the carrying value is no longer recoverable based upon the undiscounted future cash flows of the asset, the amount of the impairment is the difference between the carrying amount and the fair value of the asset. Debt Issuance Costs The costs related to the issuance of debt are capitalized, netted against the related debt for presentation purposes and amortized to interest expense over the terms of the related debt. Professional Liability The Company is self-insured (up to certain limits) for professional liability claims arising in the normal course of business, generally related to the testing and reporting of laboratory test results. The Company estimates a liability that represents the ultimate exposure for aggregate losses below those limits. The liability is based on assumptions and factors for known and incurred but not reported claims, including the frequency and payment trends of historical claims. Leases All leases with a lease term greater than 12 months, regardless of lease type classification, are recorded as an obligation on the balance sheet with a corresponding right-of-use asset. Both finance and operating leases are reflected as liabilities on the commencement date of the lease based on the present value of the lease payments to be made over the lease term. Right-of-use assets are valued at the initial measurement of the lease liability, plus any initial direct costs or rent prepayments, minus lease incentives and any deferred lease payments. The classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A certain number of these leases contain rent escalation clauses either fixed or adjusted periodically for inflation or market rates that are factored into the Company's determination of lease payments. The Company also has variable lease payments that do not depend on a rate or index, for items such as volume purchase commitments, which are recorded as variable cost when incurred. As most of the Company's leases do not provide an implicit rate, the Company estimates an incremental borrowing rate based on the credit quality of the Company and by comparing interest rates available in the market for similar borrowings, and adjusting this amount based on the impact of collateral over the term of each lease. The Company uses this rate to discount payments to present value. Some operating leases contain renewal options, some of which also include options to early terminate the leases. The exercise of these options is at the Company's discretion and the Company evaluates each renewal option to determine if it is reasonably possible to be exercised and should be included in the accounting lease term. See Note 5 Leases to the Consolidated Financial Statements. Income Taxes The Company accounts for income taxes utilizing the asset and liability method. Under this method deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and for tax loss carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company does not recognize a tax benefit unless the Company concludes that it is more likely than not that the benefit will be sustained on audit by the taxing authority based solely on the technical merits of the associated tax position. If the recognition threshold is met, the Company recognizes a tax benefit measured at the largest amount of the tax benefit that the Company believes is greater than 50% likely to be realized. The Company records interest and penalties in income tax expense. Derivative Financial Instruments The Company addresses its exposure to market risks, principally the market risk associated with changes in interest rates and currency exchange rates, through a controlled program of risk management that includes, from time to time, the use of derivative financial instruments. The Company does not hold or issue derivative financial instruments for trading purposes. The Company does not believe that its exposure to market risk is material to the Company’s financial position or results of operations. Interest rate swap agreements, which have been used by the Company from time to time in the management of interest rate exposure, are accounted for at fair value. These derivative financial instruments are accounted for as fair value hedges that increase or decrease the value of the Senior Notes with the offset being recorded as a component of other long-term assets or liabilities, as applicable. As the specific terms and notional amounts of the derivative financial instruments match those of the fixed-rate debt being hedged, the derivative instruments are assumed to be perfectly effective hedges and accordingly, there is no impact to the Company's consolidated statements of operations. Cash flows from the interest rate swaps are including in operating activities. Cross currency swap agreements, which have been used by the Company to hedge the foreign currency exposure of its net investment in a foreign subsidiary denominated in non-U.S. currency, are accounted for at fair value. Changes in the fair value of the cross-currency swaps are charged or credited through accumulated other comprehensive income in the Consolidated Balance Sheet until the hedged item is recognized in earnings. The cumulative amount of the fair value hedging adjustments are recognized as currency translation within the Consolidated Statements of Comprehensive Earnings. Foreign currency forward contracts, which have been used by the Company to hedge foreign currency receivables, are recognized as assets or liabilities at their fair value. These contracts do not qualify for hedge accounting and the changes in fair value are recorded directly to earnings. The contracts are short-term in nature and the fair value of these contracts is based on market prices for comparable contracts. The fair value of these contracts is not significant as of December 31, 2023 and 2022. Fair Value of Financial Instruments Fair value measurements for financial assets and liabilities are determined based on the assumptions that a market participant would use in pricing an asset or liability. A three-tiered fair value hierarchy draws distinctions between market participant assumptions based on (i) observable inputs such as quoted prices in active markets (Level 1), (ii) inputs other than quoted prices in active markets that are observable either directly or indirectly (Level 2), and (iii) unobservable inputs that require the Company to use present value and other valuation techniques in the determination of fair value (Level 3). Foreign Currencies For subsidiaries outside of the U.S. that operate in a local currency environment, income and expense items are translated to U.S. dollars at the monthly average rates of exchange prevailing during the period, assets and liabilities are translated at period-end exchange rates and equity accounts are translated at historical exchange rates. Translation adjustments are accumulated in a separate component of shareholders’ equity in the consolidated balance sheets and are included in the determination of comprehensive income in the consolidated statements of comprehensive earnings and consolidated statements of changes in shareholders’ equity. Transaction gains and losses are included in the determination of net income in the consolidated statements of operations.

DISCONTINUED OPERATIONS

DISCONTINUED OPERATIONS	12 Months Ended
	Dec. 31, 2023
Discontinued Operations and Disposal Groups [Abstract]
DISCONTINUED OPERATIONS	2. DISCONTINUED OPERATIONS 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: (i) a component (or group of components) meets the criteria to be classified as held for sale; (ii) the component or group of components is disposed of by sale; or (iii) 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 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 (Distribution Date). The Company received external opinions from tax counsel and a private letter ruling from the U.S. Internal Revenue Service (the “IRS”) regarding the qualification of the spin-off of Fortrea as tax-free to Fortrea, the Company and the shareholders of the Company for U.S. federal income tax purposes. In June 2023, Fortrea, prior to the spin-off 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 spin-off. The Company does not guarantee the Fortrea Notes. 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 and the service fees earned 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 spin-off-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 years ended December 31, 2023, 2022, and 2021: For the Year Ended December 31, 2023 2022 2021 Revenues $ 1,506.6 $ 3,012.9 $ 2,984.8 Cost of revenues 1,244.5 2,336.7 2,352.9 Gross profit 262.1 676.2 631.9 Selling, general and administrative expenses 184.1 233.5 261.8 Amortization of intangibles and other assets 31.9 65.7 140.1 Goodwill and other asset impairments — 9.8 — Restructuring and other charges 3.0 29.8 19.1 Operating income 43.1 337.4 210.9 Other income (expense): Interest expense (0.5) (0.5) (0.3) Investment income (expense) (1.2) 1.4 1.4 Other, net 4.2 6.9 27.0 Earnings before income taxes 45.6 345.2 239.0 Provision for income taxes 6.8 68.1 57.1 Net earnings attributable to Laboratory Corporation of America Holdings $ 38.8 $ 277.1 $ 181.9 The following table summarizes the carrying value of the significant classes of assets and liabilities classified as discontinued operations as of December 31, 2022:

REVENUE (Notes)

REVENUE (Notes)	12 Months Ended
	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
REVENUE	REVENUES Description of Revenues Dx attributes revenues to a geographical region based upon where the diagnostic test is performed, while BLS attributes revenues to a geographical region based upon where the services are performed. The Company's revenue by segment payers/customer groups for the years ended December 31, 2023, 2022 and 2021 is as follows: For the Year Ended For the Year Ended For the Year Ended North America Europe Other Total North America Europe Other Total North America Europe Other Total Payer/Customer Dx Clients 24 % — % — % 24 % 22 % — % — % 22 % 21 % — % — % 21 % Patients 9 % — % — % 9 % 8 % — % — % 8 % 7 % — % — % 7 % Medicare and Medicaid 8 % — % — % 8 % 8 % — % — % 8 % 8 % — % — % 8 % Third party 36 % — % — % 36 % 39 % — % — % 39 % 42 % — % — % 42 % Total Dx revenues by payer 77 % — % — % 77 % 77 % — % — % 77 % 78 % — % — % 78 % BLS Pharmaceutical, biotechnology and medical device companies 10 % 9 % 4 % 23 % 10 % 9 % 4 % 23 % 10 % 9 % 3 % 22 % Total revenues 87 % 9 % 4 % 100 % 87 % 9 % 4 % 100 % 88 % 9 % 3 % 100 % Revenues in the U.S. were $10,177.7 (83.7%), $9,930.3 (83.7%) and $10,981.2 (83.6%) for the years ended December 31, 2023, 2022, and 2021. The following is a description of the current revenue recognition policies of the Company: Dx Revenues Dx is an independent clinical laboratory business. It offers a comprehensive menu of frequently requested and specialty diagnostic tests through an integrated network of primary and specialty laboratories across the U.S. In addition to diagnostic testing along with occupational and wellness testing for employers and forensic DNA analysis, Dx also offered a range of other testing services. Within the Dx segment, a majority of the revenue transactions initiated when Dx receives a requisition order to perform a diagnostic test. The information provided on the requisition form is used to determine the party that will be billed for the testing performed and the expected reimbursement. Dx recognizes revenue and satisfies its performance obligation for services rendered when the testing process is complete and the associated results are reported. The Dx segment also enters into agreements that have monthly and non-testing based fees which are recognized each month as the services are provided. Revenues are distributed among four payer portfolios - clients, patients, Medicare and Medicaid and third party. Dx considers negotiated discounts and anticipated adjustments, including historical collection experience for the payer portfolio, when revenues are recorded. The following are descriptions of the Dx payer portfolios: Clients Client payers represent the portion of Dx’s revenue related to physicians, hospitals, health systems, accountable care organizations (ACOs), employers and other entities where payment is received exclusively from the entity ordering the testing service. Generally, client sales are recorded on a fee-for-service basis at Dx’s client list price, less any negotiated discount. A portion of client billing is for laboratory management services, collection kits and other non-testing services or products. In these cases, revenue is recognized when services are rendered or delivered. Patients This portfolio includes revenue from uninsured patients and member cost-share for insured patients (e.g., coinsurance, deductibles and non-covered services). Uninsured patients are billed based upon Dx’s patient list fee schedules, net of any discounts negotiated with physicians on behalf of their patients. Dx bills insured patients as directed by their health plan and after consideration of the fees and terms associated with an established health plan contract. Medicare and Medicaid This portfolio relates to fee-for-service revenue from traditional Medicare and Medicaid programs. Revenue from these programs is based on the fee schedule established by the related government authority. In addition to contractual discounts, other adjustments including anticipated payer denials are considered when determining revenue. Any remaining adjustments to revenue are recorded at the time of final collection and settlement. These adjustments are not material to Dx’s results of operations in any period presented . Third Party Third party includes revenue related to managed care organizations (MCOs). The majority of Dx's third-party revenue is reimbursed on a fee-for-service basis. These payers are billed at Dx's established list price and revenue is recorded net of contractual discounts. The majority of Dx’s MCO sales are recorded based upon contractually negotiated fee schedules with sales for non-contracted MCOs recorded based on historical reimbursement experience. In addition to contractual discounts, other adjustments including anticipated payer denials are considered when determining revenue. Any remaining adjustments to revenue are recorded at the time of final collection and settlement. These adjustments are not material to Dx’s results of operations in any period presented. Third-party reimbursement is also received through capitation agreements with MCOs and independent physician associations. Under capitated agreements, revenue is recognized based on a negotiated per-member, per-month payment for an agreed upon menu of tests, or based upon the proportionate share earned by Dx from a capitation pool. When the agreed upon reimbursement is based solely on an established rate per member, revenue is not impacted by the volume of testing performed. Under a capitation pool arrangement, the aggregate value of an established rate per member is distributed based on the volume and complexity of the procedures performed by laboratories participating in the agreement. Dx recognizes revenue monthly, based upon the established capitation rate or anticipated distribution from a capitated pool. BLS Revenues BLS revenue is generally recognized over time, as the services are delivered to the customer, based on the extent of progress towards completion of the performance obligation. The selection of the method to measure progress towards completion requires judgment and is based on the nature of the products or services to be provided. The majority of the segment's contracts contain a single performance obligation, as the segment provides a significant service of integrating all promises in the contract and the promises are highly interdependent and interrelated with one another. For contracts that include multiple performance obligations, BLS allocates the contract value to the goods and services based on a customer price list, if available. If a price list is not available, BLS will estimate the transaction price using either market prices or an “expected cost plus margin” approach. The total contract value is estimated at the beginning of the contract, and is equal to the amount expected to be billed to the customer. These contracts generally take the form of fixed-price or fee-for-service arrangements subject to pricing adjustments based on changes in scope. Fixed-price contracts are typically recognized as revenue over time based on a proportional-performance basis, using either input or output methods that are specific to the service provided. In an output method, revenue is determined by dividing the actual units of output achieved by the total units of output required under the contract and multiplying that percentage by the total contract value. When using an input method, revenue is recognized by dividing the actual costs incurred by the total estimated cost expected to complete the contract, and multiplying that percentage by the total contract value. Contract costs principally include direct labor costs, research model costs and allocated overhead. The estimate of total costs expected to complete the contract requires significant judgment, and these estimates are reviewed periodically. Any adjustments to the estimates are recognized on a cumulative catch-up basis in the period they become known. Fee-for-service contracts are typically priced based on transaction volume or time and materials. For volume-based contracts the contract value is entirely variable and revenue is recognized as the specific product or service is completed. For services billed based on time and materials, revenue is recognized using the right to invoice practical expedient. Contracts are often modified to account for changes in contract specifications and requirements. Generally, when contract modifications create new performance obligations, the modification is considered to be a separate contract and revenue is recognized prospectively. When contract modifications change existing performance obligations, the impact on the existing transaction price and measure of progress for the performance obligation to which it relates is generally recognized as an adjustment to revenue (either as an increase in or a reduction of revenue) on a cumulative catch-up basis. Most contracts are terminable with or without cause by the customer, either immediately or upon notice. These contracts often require payment to BLS of expenses, fees earned to date and, in some cases, a termination fee or a payment to BLS of some portion of the fees or profits that could have been earned by BLS under the contract if it had not been terminated early. Termination fees are included in revenues when services have been performed and realization is assured. BLS incurs sales commissions in the process of obtaining contracts with customers, which are recoverable through the service fees in the contract. Sales commissions that are payable upon contract award are recognized as assets and amortized over the expected contract term, along with related payroll tax expense. The amortization of commission expense is based on the weighted average contract duration for all commissionable awards in the respective business in which the commission expense is paid, which approximates the period over which goods and services are transferred to the customer. The amortization period of sales commissions ranges from approximately 1 to 5 years, depending on the business. For businesses that enter primarily short-term contracts, BLS applies the practical expedient which allows costs to obtain a contract to be expensed when incurred if the amortization period of the assets that would otherwise have been recognized is one year or less. Amortization of assets from sales commissions is included in selling, general, and administrative expense. BLS incurs costs to fulfill contracts with customers, which are recoverable through the service fees in the contract. Contract fulfillment costs include software implementation costs and setup costs for certain services. These costs are recognized as assets and amortized over the expected term of the contract to which the implementation relates, which is the period over which services are expected to be provided to the customer. This period typically ranges from 2 to 5 years. Amortization of deferred contract fulfillment costs is included in cost of goods sold. Accounts Receivable, Unbilled Services and Unearned Revenue Differences in the timing of revenue recognition and associated billing and cash collections result in recording accounts receivable, unbilled services and unearned revenue in the consolidated balance sheet. Payments received in advance of services being provided are contract liabilities recognized as unearned revenue. Revenue recognized in advance of billing are recognized as unbilled services and the majority of BLS's unbilled services represent unbilled receivables. Once a customer is invoiced, the contract asset is reduced for the amount billed, and a corresponding accounts receivable is recognized. All contract assets are billable to customers within one year from the respective balance sheet date. The following table provides information about accounts receivable, unbilled services, and unearned revenue from contracts with customers: December 31, 2023 December 31, 2022 Dx accounts receivable $ 1,135.2 $ 1,046.9 BLS accounts receivable 810.8 769.4 Less BLS allowance for doubtful accounts (32.7) (30.8) Accounts receivable $ 1,913.3 $ 1,785.5 Gross unbilled services $ 192.9 $ 222.3 Less reserve for unbilled services (7.5) (10.6) Unbilled services $ 185.4 $ 211.8 Unearned revenue $ 421.7 $ 310.6 Revenue recognized during the period, that was included in the unearned revenue balance at the beginning of the period, for the years ended December 31, 2023, 2022, and 2021 was $78.9, $99.7, and $110.7, respectively. Credit Loss Rollforward BLS 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 year ended December 31, 2023, is as follows: Accounts Receivable Unbilled Services Note and Other Receivables Total Allowance for credit losses as of December 31, 2021 $ 9.8 $ 13.9 $ 0.7 $ 24.4 Credit loss expense 11.7 — — 11.7 Write offs 9.3 (3.4) — 5.9 Allowance for credit losses as of December 31, 2022 $ 30.8 $ 10.5 $ 0.7 $ 42.0 Credit loss expense 6.3 — — 6.3 Write offs (4.4) (3.0) — (7.4) Ending allowance for credit losses as of December 31, 2023 $ 32.7 $ 7.5 $ 0.7 $ 40.9

BUSINESS ACQUISITIONS

BUSINESS ACQUISITIONS	12 Months Ended
	Dec. 31, 2023
Business Combinations [Abstract]
BUSINESS ACQUISITIONS	BUSINESS ACQUISITIONS AND DISPOSITIONS 2023 During the year ended December 31, 2023, the Company acquired several businesses and related assets for cash of approximately $671.5. 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 $340.8 in identifiable intangible assets and a residual amount of tax-deductible goodwill of approximately $296.9 The goodwill reflects the Company's expectations to utilize the acquired businesses’ workforce and established relationships and the benefits of being able to leverage operational efficiencies with favorable growth opportunities in these markets. The amortization period for non-compete agreements and customer list assets acquired from these businesses are 5 and 15 years, respectively. These acquisitions were made primarily to extend the Company's geographic reach in important market areas and to partner with hospitals and health systems. The purchase price allocations for these acquisitions have not been finalized as of December 31, 2023. The preliminary valuation of acquired assets and assumed liabilities, include the following: Jefferson Health Enzo BioChem Providence Health and Services - Oregon Tufts Medicine Legacy Other Business Acquisitions Measurement Period Adjustments Amounts Acquired During the Year Ended December 31, 2023 Accounts receivable $ — $ (2.8) $ — $ — $ — $ 2.0 $ 0.2 $ (0.6) Inventories — — 1.3 — — — — 1.3 Prepaid expenses and other — 0.4 — — 0.2 0.3 0.6 1.5 Property, plant and equipment — — 4.7 — 3.3 6.5 (1.5) 13.0 Goodwill 50.8 54.1 50.7 73.8 49.0 18.5 (29.4) 267.5 Intangible assets 57.2 61.1 57.2 83.2 55.2 26.9 19.5 360.3 Other assets 2.2 — — — — 17.9 — 20.1 Total assets acquired 110.2 112.8 113.9 157.0 107.7 72.1 (10.6) 663.1 Accounts payable — — — — — 1.2 — 1.2 Accrued expenses and other — — 3.9 — — 1.2 (8.3) (3.2) Deferred income taxes — — — — — — (2.3) (2.3) Other liabilities — — — — — (4.1) — (4.1) Total liabilities acquired — — 3.9 — — (1.7) (10.6) (8.4) Net assets acquired $ 110.2 $ 112.8 $ 110.0 $ 157.0 $ 107.7 $ 73.8 $ — $ 671.5 Unaudited Pro Forma Information for 2023 Acquisitions Had the aggregate of the Company's 2023 acquisitions been completed as of January 1, 2022, the Company's pro forma results would have been as follows: Years Ended December 31, 2023 2022 Revenues $ 12,350.1 $ 12,126.3 Earnings from continuing operations 397.2 1,030.3 2022 During the year ended December 31, 2022, the Company acquired various businesses and related assets for approximately $1,164.0 in cash (net of cash acquired). The purchase consideration for all acquisitions year to date has been allocated to the estimated fair market value of the net assets acquired, including approximately $542.3 in identifiable intangible assets and a residual amount of non-tax-deductible goodwill of approximately $598.5. The amortization periods for intangible assets acquired from these transactions range from 15 to 19 years for customer relationships, 15 years for patents and technology, 5 years for non-compete agreements, and 5 to 10 years for trade names. These acquisitions were made primarily to extend the Company's geographic reach in important market areas and enhance the Company's scientific differentiation. The excess of the fair value of the consideration conveyed over the fair value of the net assets acquired was recorded as goodwill. The goodwill reflects the Company's expectations to utilize the acquired businesses’ workforce and established relationships and the benefits of being able to leverage operational efficiencies with favorable growth opportunities in these markets. The purchase price allocation for several of these transaction was preliminary for the year ended December 31, 2022. The areas of the purchase price allocation that were not yet finalized related primarily to property, plant and equipment, intangible assets, goodwill and deferred income taxes. A summary of the net assets acquired in 2022 for these businesses is included below: Preliminary Personal Genome Diagnostics Inc. Preliminary Ascension Healthcare Other Acquisitions Measurement Period Adjustments Amounts Acquired During Year Ended December 31, 2022 Accounts receivable $ 4.1 $ — $ (1.3) $ (2.3) $ 0.5 Unbilled services 2.9 — — (3.2) (0.3) Inventories 2.5 24.6 — — 27.1 Prepaid expenses and other 1.2 0.4 0.3 — 1.9 Property, plant and equipment 9.9 43.5 0.1 — 53.5 Deferred income taxes 17.5 — — 15.2 32.7 Goodwill 346.8 125.0 126.7 (40.4) 558.1 Intangible assets 136.6 233.2 172.5 30.4 572.7 Other assets 12.5 — 2.3 (2.3) 12.5 Total assets acquired 534.0 426.7 300.6 (2.6) 1,258.7 Accounts payable 3.8 — — (0.1) 3.7 Accrued expenses and other 57.3 — 15.4 0.1 72.8 Unearned revenue 3.3 — — (2.6) 0.7 Lease liabilities — 2.9 — — 2.9 Other liabilities 14.6 — — — 14.6 Total liabilities acquired 79.0 2.9 15.4 (2.6) 94.7 Net assets acquired $ 455.0 $ 423.8 $ 285.2 $ — $ 1,164.0 Unaudited Pro Forma Information for 2022 Acquisitions Had the aggregate of the Company's 2022 acquisitions been completed as of January 1, 2021, the Company's pro forma results would have been as follows: Years Ended December 31, 2022 2021 Revenues $ 11,984.7 $ 13,325.7 Earnings from continuing operations 1,006.8 2,182.4 2021 During the year ended December 31, 2021, the Company acquired various businesses and related assets for approximately $496.9 in cash (net of cash acquired). The purchase consideration for all acquisitions year to date has been allocated to the estimated fair market value of the net assets acquired, including approximately $198.5 in identifiable intangible assets and a residual amount of non-tax-deductible goodwill of approximately $298.4. The amortization periods for intangible assets acquired from these businesses range from 15 to 19 years for customer relationships, 5 to 15 years for patents and technology, 5 years for non-compete agreements, and 10 years for trade names. These acquisitions were made primarily to extend the Company's geographic reach in important market areas and enhance the Company's scientific differentiation. The excess of the fair value of the consideration conveyed over the fair value of the net assets acquired was recorded as goodwill. The goodwill reflects the Company's expectations to utilize the acquired businesses’ workforce and established relationships and the benefits of being able to leverage operational efficiencies with favorable growth opportunities in these markets. A summary of the net assets acquired in 2021 for these businesses is included below: Amounts Acquired During Year Ended December 31, 2021 Accounts receivable $ 10.8 Unbilled services 3.2 Inventories 1.6 Prepaid expenses and other 3.0 Property, plant and equipment 56.6 Goodwill 298.4 Intangible assets 198.5 Total assets acquired 572.1 Accounts payable 2.5 Accrued expenses and other 3.9 Unearned revenue 6.6 Other liabilities 62.2 Total liabilities acquired 75.2 Net assets acquired $ 496.9 Unaudited Pro Forma Information for 2021 Acquisitions Had the aggregate of the Company's 2021 acquisitions been completed as of January 1, 2021, the Company's pro forma results would have been as follows: Years Ended December 31, 2021 Revenues $ 13,231.8 Earnings from continuing operations 2,198.6

Restructuring and Related Activ

Restructuring and Related Activities	12 Months Ended
	Dec. 31, 2023
Restructuring and Related Activities [Abstract]
RESTRUCTURING AND OTHER SPECIAL CHARGES	. RESTRUCTURING AND OTHER CHARGES During 2023, the Company recorded net restructuring charges of $49.1. The charges were comprised of $33.4 in severance and other personnel costs, $22.3 in facility-related costs primarily associated with general integration activities. The charges were offset by the reversal of a previously established liability of $1.7 in unused severance and $4.9 in unused facility-related costs. During 2022, the Company recorded net restructuring charges of $54.0. The charges were comprised of $24.8 in severance and other personnel costs and $31.1 in facility-related costs primarily associated with general integration activities. The charges were offset by the reversal of a previously established liability of $1.4 in unused severance and $0.5 in unused facility-related costs. During 2021, the Company recorded net restructuring charges of $24.0. The charges were comprised of $12.4 in severance and other personnel costs, $12.0 in facility-related costs primarily associated with general integration activities. The charges were offset by the reversal of a previously established liability of $0.3 in unused severance and $0.2 in unused facility-related costs. The following represents the Company’s restructuring activities for the period indicated: Severance and Other Lease and Other Total Balance as of December 31, 2021 $ 3.7 $ 1.6 $ 5.3 Restructuring charges 24.8 31.1 55.9 Reduction of prior restructuring accruals (1.4) (0.5) (1.9) Cash payments and other adjustments (25.0) (22.8) (47.8) Balance as of December 31, 2022 2.1 9.4 11.5 Restructuring charges 33.4 22.3 55.7 Reduction of prior restructuring accruals (1.7) (4.9) (6.6) Cash payments and other adjustments (26.2) (13.8) (40.0) Balance as of December 31, 2023 $ 7.6 $ 13.0 $ 20.6 Current $ 9.5 Non-current 11.1 $ 20.6 The non-current portion of the restructuring liabilities is expected to be paid out over 9.7 years. Cash payments and other adjustments include the reclassification of profit sharing, pension, and holiday accrual.

LEASES (Notes)

LEASES (Notes)	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Leases of Lessee Disclosure [Text Block]	LEASES The Company has operating and finance leases for patient service centers, laboratories and testing facilities, clinical facilities, general office spaces, vehicles, and office and laboratory equipment. Leases have remaining lease terms of less than a year to 15 years, some of which include options to extend the leases for up to 15 years. The components of lease expense were as follows: For the Year Ended December 31, 2023 December 31, 2022 Operating lease cost $ 202.6 $ 198.1 Finance lease cost: Amortization of right-of-use assets $ 7.1 $ 8.0 Interest on lease liabilities 4.8 5.2 Total finance lease cost $ 11.9 $ 13.2 Supplemental cash flow information related to leases was as follows: For the Year Ended December 31, 2023 December 31, 2022 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ (209.7) $ (200.2) Operating cash flows from finance leases (4.8) (5.2) Financing cash flows from finance leases (12.6) (12.3) ROU assets obtained in exchange for lease obligations: Operating leases $ 106.4 $ 159.2 Finance leases 2.3 — Supplemental balance sheet information related to leases was as follows: December 31, 2023 December 31, 2022 Operating Leases Operating lease ROU assets (included in Property, plant and equipment, net) $ 737.1 $ 738.1 Short-term operating lease liabilities 165.8 163.8 Operating lease liabilities 648.9 652.9 Total operating lease liabilities $ 814.7 $ 816.7 Finance Leases Finance lease ROU assets (included in Other assets) $ 69.5 $ 74.9 Short-term finance lease liabilities 6.4 6.0 Financing lease liabilities 78.6 83.6 Total finance lease liabilities $ 85.0 $ 89.6 Weighted Average Remaining Lease Term Operating leases 8.4 9.0 Finance leases 14.7 15.6 Weighted Average Discount Rate Operating leases 4.1 % 3.6 % Finance leases 5.3 % 5.5 % Maturities of lease liabilities are as follows: Year Ended December 31, 2023 Operating Leases Finance Leases 2024 $ 200.1 $ 11.3 2025 161.2 9.2 2026 114.1 8.6 2027 86.1 8.2 2028 70.7 7.6 Thereafter 330.1 78.3 Total lease payments $ 962.3 $ 123.2 Less imputed interest (147.6) (38.2) Less current portion (165.8) (6.4) Total maturities, due beyond one year $ 648.9 $ 78.6 Rent expense for short term leases with a term less than one year for the years ended December 31, 2023, 2022, and 2021 amounted to $31.9, $22.2, $19.5, respectively. The Company has variable lease payments that do not depend on a rate index, primarily for purchase volume commitments, which are recorded as variable cost when incurred. Total variable payments for the year ended December 31, 2023, 2022 and 2021 were $32.7

PROPERTY, PLANT AND EQUIPMENT,

PROPERTY, PLANT AND EQUIPMENT, NET	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
PROPERTY, PLANT AND EQUIPMENT, NET	PROPERTY, PLANT AND EQUIPMENT, NET December 31, 2023 December 31, 2022 Land $ 98.8 $ 98.5 Buildings and building improvements 1,083.8 1,009.8 Machinery and equipment 2,008.0 1,820.4 Software 924.7 811.6 Leasehold improvements 515.8 484.0 Furniture and fixtures 106.5 109.6 Construction in progress 342.2 306.5 Operating lease ROU assets 737.1 738.1 5,816.9 5,378.5 Less accumulated depreciation (2,905.1) (2,584.4) $ 2,911.8 $ 2,794.1 Depreciation expense and amortization of property, plant and equipment was $361.1, $343.6 and $347.6 for 2023, 2022 and 2021, respectively, including software amortization of $76.6, $75.7, and $73.7 for 2023, 2022 and 2021, respectively.

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND INTANGIBLE ASSETS	GOODWILL AND INTANGIBLE ASSETS The changes in the carrying amount of goodwill (net of impairment) for the years ended December 31, 2023 and 2022 were as follows: Dx BLS Total December 31, 2023 December 31, 2022 December 31, 2023 December 31, 2022 December 31, 2023 December 31, 2022 Balance as of January 1 $ 4,533.5 $ 4,046.2 $ 1,590.2 $ 1,844.8 $ 6,123.7 $ 5,891.0 Goodwill acquired during the year 296.9 557.9 — 40.6 296.9 598.5 Impairment — — (333.6) (260.0) (333.6) (260.0) Foreign currency impact and other adjustments to goodwill (16.5) (70.6) 72.0 (35.2) 55.5 (105.8) Balance at end of year $ 4,813.9 $ 4,533.5 $ 1,328.6 $ 1,590.2 $ 6,142.5 $ 6,123.7 The components of identifiable intangible assets are as follows: December 31, 2023 December 31, 2022 Gross Accumulated Net Gross Accumulated Net Customer relationships $ 3,868.6 $ (1,367.2) $ 2,501.4 $ 3,490.0 $ (1,169.7) $ 2,320.3 Patents, licenses and technology 526.6 (273.3) 253.3 520.4 (243.3) 277.1 Non-compete agreements 130.3 (60.4) 69.9 80.1 (46.8) 33.3 Trade names 16.4 (6.1) 10.3 16.4 (3.5) 12.9 Land use rights 3.5 (2.7) 0.8 3.5 (2.2) 1.3 Canadian licenses 498.8 — 498.8 468.7 — 468.7 Content 5.1 (4.7) 0.4 5.1 (4.2) 0.9 In process research and development 9.1 (2.0) 7.1 9.1 — 9.1 $ 5,058.4 $ (1,716.4) $ 3,342.0 $ 4,593.3 $ (1,469.7) $ 3,123.6 During 2023, the Company recorded goodwill and other asset impairment charges of $349.0 which was primarily comprised of $333.6 of goodwill impairment for the ED reporting unit. During 2022, the Company recorded goodwill and other asset impairment charges of $261.7 which was primarily comprised of goodwill impairment and the impairment of a technology intangible asset. The cumulative goodwill impairment for the Company through December 31, 2023 was $648.5 and relates completely to the ED reporting unit of the BLS segment. In December 2020, the Company undertook a rebranding initiative and reduced the estimated useful life of its trade name assets to reflect their anticipated use through December 2021. This change in estimated useful life resulted in accelerated amortization of $30.8 in 2021. A summary of amortizable intangible assets acquired during 2023, and their respective weighted average amortization periods are as follows: Amount Weighted Average Customer relationships $ 260.6 12.5 Non-compete agreements 53.3 0.8 $ 313.9 13.3 Amortization of intangible assets was $219.8, $193.6 and $229.5 in 2023, 2022 and 2021, respectively. Amortization expense of intangible assets is estimated to be $235.4 in fiscal 2024, $225.7 in fiscal 2025, $216.8 in fiscal 2026, $205.5 in fiscal 2027, $197.3 in fiscal 2028, and $1,675.0 thereafter.

ACCRUED EXPENSES AND OTHER

ACCRUED EXPENSES AND OTHER	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
ACCRUED EXPENSES AND OTHER	ACCRUED EXPENSES AND OTHER December 31, 2023 December 31, 2022 Employee compensation and benefits $ 431.4 $ 444.6 Accrued taxes payable 127.5 105.6 Other 245.1 236.8 $ 804.0 $ 787.0

DEBT

DEBT	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
DEBT	DEBT Short-term borrowings and current portion of long-term debt at December 31, 2023, and 2022 consisted of the following: December 31, 2023 December 31, 2022 4.00% senior notes due 2023 — 300.0 2.30% senior notes due 2024 400.0 — 3.25% senior note due 2024 600.0 — Debt issuance costs (1.3) (0.4) Current portion of note payable 1.1 1.7 Total short-term borrowings and current portion of long-term debt $ 999.8 $ 301.3 Long-term debt at December 31, 2023, and 2022 consisted of the following: December 31, 2023 December 31, 2022 2.30% senior notes due 2024 — 400.0 3.25% senior notes due 2024 — 600.0 3.60% senior notes due 2025 1,000.0 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 2.70% senior notes due 2031 430.4 420.3 4.70% senior notes due 2045 900.0 900.0 Debt issuance costs (26.3) (33.8) Note payable 0.6 2.3 Total long-term debt $ 4,054.7 $ 5,038.8 Credit Facilities On June 3, 2019, the Company entered into a $850.0 term loan (the 2019 Term Loan). The Company fully repaid the remaining 2019 Term Loan balance during the first quarter of 2021. The Company maintains a senior revolving credit facility, which was amended and restated on April 30, 2021. It consists of a five-year revolving facility in the principal amount of up to $1,000.0, with the option of increasing the facility by up to an additional $500.0, subject to the agreement of one or more new or existing lenders to provide such additional amounts and certain other customary conditions. The revolving credit facility also provides for a subfacility of up to $100.0 for swing line borrowings and a subfacility of up to $150.0 for issuances of letters of credit. The Company is required to pay a facility fee on the aggregate commitments under the revolving credit facility, at a per annum rate ranging from 0.10% to 0.225%, depending on the Company's debt ratings. The revolving credit facility is permitted to be used for general corporate purposes, including working capital, capital expenditures, funding of share repurchases and certain other payments, acquisitions, and other investments. There were no balances outstanding on the Company's current revolving credit facility at December 31, 2023, or December 31, 2022. As of December 31, 2023, the effective interest rate on the revolving credit facility was 6.44%. The credit facility expires on April 30, 2026. Under the Company's the revolving credit facility, the Company is subject to negative covenants limiting subsidiary indebtedness and certain other covenants typical for investment grade-rated borrowers and the Company is required to maintain certain leverage ratios. The Company was in compliance with all covenants in its term loans and the revolving credit facility at December 31, 2023, and expects that it will remain in compliance with its existing debt covenants for the next twelve months. There were $91.3 in outstanding letters of credit as of December 31, 2023. The scheduled payments of long-term debt at the end of 2023 are summarized as follows: 2024 $ 1,001.1 2025 1,000.0 2026 500.0 2027 600.0 2028 — Thereafter 1,981.0 Total scheduled payments 5,082.1 Less current portion (1,001.1) Long-term debt, due beyond one year $ 4,081.0

PREFERRED STOCK AND COMMON SHAR

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
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 December 31, 2023 and 2022. The changes in common shares issued and held in treasury are summarized below: Common Shares Issued 2023 2022 2021 Common stock issued at January 1 88.2 93.1 97.5 Common stock issued under employee stock plans 0.5 0.7 0.8 Purchase of common stock (4.8) (5.6) (5.2) Common stock issued at December 31 83.9 88.2 93.1 The Company’s treasury shares are recorded at aggregate cost. Share Repurchase Program On August 8, 2023, the Company entered into accelerated share repurchase agreements (collectively, the ASR Agreements) with two different banks, Goldman Sachs & Co. LLC and Morgan Stanley & Co. LLC (collectively, the Financial Institutions), to repurchase approximately $1,000.0 in the aggregate of the Company’s Common Stock (Common Stock), as part of the Company’s Common Stock repurchase program. The remaining repurchase authorization has no expiration date. Under the ASR Agreements, the Company made an aggregate payment of $1,000.0 to the Financial Institutions and received an aggregate initial number of approximately 3.7 shares of Common Stock from the Financial Institutions, which were removed from the outstanding share count in connection with entering into the ASR Agreements. In December 2023, the Company received 1.1 shares of its Common Stock as a final settlement from the Financial Institutions. The average daily volume weighted average price less discount per share was $206.85. The Company has accrued $9.0 of excise tax related to this accelerated share repurchase which will be paid in April 2024. During the fourth quarter of 2021, the board of directors (the Board) adopted a new share repurchase plan authorizing up to $2,500.0 of the Company's shares in addition to the remaining amount outstanding under the previous plan. Under this plan, the Company commenced an Accelerated Share Repurchase (ASR) program. At inception, the Company paid $1,000.0 and received 2.7 shares based on a calculation using 80% of the shares calculated at the price at the inception of the ASR agreements with two different banks, Goldman Sachs & Co. LLC and Barclays Bank PLC. The initial shares received under the ASR program were removed from the outstanding share count in 2021. During the twelve months ended December 31, 2022, 0.9 shares were retired as part of this ASR program. Additionally, during the twelve months ended December 31, 2022, the Company repurchased 4.7 shares of Common Stock at an average price of $233.48 per share for a total cost of $1,100.0. During 2021, the Company repurchased 5.2 shares of its common stock at an average price of $282.05 for a total cost of $1,668.5, which included $1,000.0 paid as part of an ASR. 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 December 31, 2023 the remaining total available authorization was under the ASR was $530.4. Dividends For the twelve months ended December 31, 2023, the Company paid $254.0 in Common Stock dividends. On January 12, 2024, the Company announced a cash dividend of $0.72 per share of Common Stock for the first quarter, or approximately $61.5 in the aggregate. The dividend will be payable on March 13, 2024, to stockholders of record of all issued and outstanding shares of Common Stock as of the close of business on February 27, 2024. The declaration and payment of any future dividends will be at the discretion of the Company's Board. Accumulated Other Comprehensive Earnings The components of accumulated other comprehensive earnings are as follows: Foreign Net Accumulated Balance at December 31, 2021 $ (125.9) $ (66.0) $ (191.9) Current year adjustments (335.5) 52.5 (283.0) Pension settlement charge — (3.1) (3.1) Amounts reclassified from accumulated other comprehensive earnings (a) (0.9) (4.6) (5.5) Tax effect of adjustments — (9.7) (9.7) Balance at December 31, 2022 $ (462.3) $ (30.9) $ (493.2) Fortrea Holdings Inc. spin 231.6 6.4 238.0 Current year adjustments 183.1 30.1 213.2 Pension settlement charge — (10.9) (10.9) Amounts reclassified from accumulated other comprehensive earnings (a) — (4.6) (4.6) Tax effect of adjustments — (1.8) (1.8) Balance at December 31, 2023 $ (47.6) $ (11.7) $ (59.3) (a)

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The sources of income before taxes, classified between domestic and foreign entities, are as follows: 2023 2022 2021 Domestic $ 504.0 $ 1,097.9 $ 2,455.0 Foreign 64.9 139.5 432.6 Total pre-tax income $ 568.9 $ 1,237.4 $ 2,887.6 The components of income tax expense attributable to continuing operations are as follows: Years Ended December 31, 2023 2022 2021 Current tax expense: Federal $ 183.1 $ 150.8 $ 500.0 State 38.9 25.4 156.5 Foreign 44.6 34.0 71.9 $ 266.6 $ 210.2 $ 728.4 Deferred tax expense/(benefit): Federal $ (63.1) $ 15.8 $ (36.7) State (31.6) 0.6 (9.0) Foreign 16.6 7.3 7.3 (78.1) 23.7 (38.4) Total income tax expense $ 188.5 $ 233.9 $ 690.0 The effective tax rates on earnings before income taxes are reconciled to statutory U.S. income tax rates as follows: Years Ended December 31, 2023 2022 2021 Statutory U.S. rate 21.0 % 21.0 % 21.0 % State and local income taxes, net of U.S. federal income tax effect 4.0 4.2 3.9 Foreign earnings taxed at lower rates than the statutory U.S. rate (2.2) (0.7) (0.7) Tax credits (3.8) (5.4) (0.1) Impairment of assets 10.8 3.7 — Limitation of officer compensation 1.7 1.2 0.3 Worthless stock loss (2.6) — — Deferred tax adjustments 2.7 (2.4) (0.1) Other 1.5 (2.7) (0.4) Effective rate 33.1 % 18.9 % 23.9 % The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are as follows: December 31, 2023 December 31, 2022 Deferred tax assets: Accounts receivable $ 27.9 $ 19.4 Employee compensation and benefits 81.7 96.5 Operating lease liability 191.4 182.6 Acquisition and restructuring reserves 9.2 7.0 Capitalized R&D costs 142.9 44.1 Tax loss carryforwards 246.9 241.9 Other 95.1 95.1 Total gross deferred tax assets 795.1 686.6 Less: valuation allowance (150.2) (151.3) Deferred tax assets, net of valuation allowance $ 644.9 $ 535.3 Deferred tax liabilities: Right of use asset $ (175.3) $ (170.2) Intangible assets (614.8) (605.1) Property, plant and equipment (163.5) (166.5) Other (66.2) (62.7) Total gross deferred tax liabilities $ (1,019.8) $ (1,004.5) Net deferred tax liabilities $ (374.9) $ (469.2) The table below provides a rollforward of the valuation allowance: December 31, 2023 December 31, 2022 December 31, 2021 Beginning balance $ 151.3 $ 149.2 $ 167.6 Movements charged to expense (8.9) 10.2 6.8 Reductions and other adjustments 7.8 (8.1) (25.2) Ending balance $ 150.2 $ 151.3 $ 149.2 The Company has U.S. federal tax loss carryforwards of approximately $127.0, which expire periodically through 2037, as well as post-2017 carryforwards of $179.1 that are limited to 80% of taxable income and have an indefinite carryforward period. The utilization of tax loss carryforwards is limited due to change of ownership rules; however, at this time, the Company expects to fully utilize substantially all U.S. federal tax loss carryforwards with the exception of approximately $8.4 for which a full valuation allowance has been provided. The Company has U.S. state tax loss carryforwards of $442.8, a portion of which expire annually, and on which a valuation allowance of $403.0 has been provided. In addition to federal and state tax loss carryforwards, the Company has other federal and state attribute carryforwards of $114.4. A portion of these attribute carryforwards will expire through 2024 and have a valuation allowance of $69.2 while the remainder have indefinite carryforward periods. The Company has foreign tax loss carryforwards of $117.2, the majority of which have indefinite carryforward periods, but a valuation allowance of $7.9 has been provided for jurisdictions where the future tax benefits of the attributes are not more likely than not to be realized. Additionally, the Company has foreign tax loss carryforwards of $444.3 which expire periodically through 2038 and foreign tax loss carryforwards of $14.5 which expire periodically through 2043 that have full valuation allowances. In addition to the foreign net operating losses, the Company has a foreign capital loss carryforward of $27.4 with an indefinite carryforward period and a full valuation allowance. The valuation allowance decreased from $151.3 in 2022 to $150.2 in 2023 primarily due to releases of valuation allowances on certain U.S. capital losses and state net operating losses which were offset by the establishment of valuation allowances on acquired net operating losses recorded through purchase accounting. Unrecognized income tax benefits were $29.9 and $37.5 at December 31, 2023, and 2022, respectively. It is anticipated that the amount of the unrecognized income tax benefits will decrease by $0.2 within the next 12 months due to statute of limitation lapses; however, these changes are not expected to have a significant impact on the results of operations, cash flows or the financial position of the Company. The Company recognizes interest and penalties related to unrecognized income tax benefits in income tax expense. Accrued interest and penalties related to uncertain tax positions totaled $0.1 and $2.3 as of December 31, 2023, and 2022, respectively. During the years ended December 31, 2023, 2022 and 2021, the Company recognized $0.0, $0.8 and $0.0, respectively, in interest and penalties expense, which was offset by a benefit from reversing previous accruals for interest and penalties of $1.8, $0.0 and $1.1, respectively. The following table shows a reconciliation of the unrecognized income tax benefits, excluding interest and penalties, from uncertain tax positions for the years ended December 31, 2023, 2022 and 2021: 2023 2022 2021 Balance as of January 1 $ 37.5 $ 39.6 $ 18.6 Increase in reserve for tax positions taken in the current year 1.8 1.8 — Increase in reserve for tax positions taken in a prior period 10.4 10.6 31.1 Decrease in reserve for tax positions taken in a prior period (4.0) — (8.1) Decrease in reserve as a result of settlements (7.2) (10.4) — Decrease in reserve as a result of lapses in the statute of limitations (8.6) (4.1) (2.0) Balance as of December 31 $ 29.9 $ 37.5 $ 39.6 Also included in the balance of unrecognized tax benefits as of December 31, 2023, 2022 and 2021, are $0.0, $0.0 and $0.9, respectively, of tax benefits that, if recognized, would result in adjustments to other tax accounts, primarily deferred taxes. As of December 31, 2023, 2022 and 2021 there are $29.9, $37.5 and $38.7, respectively, of tax benefits that, if recognized, would favorably impact the effective income tax rate. The Company has substantially concluded all U.S. federal income tax matters for years through 2018 and is currently under IRS examination for tax years 2019 and 2020. Substantially all material state and local and foreign income tax matters have been concluded through 2017 and 2018, respectively. The Company has various state and foreign income tax examinations ongoing throughout the year. The Company believes adequate provisions have been recorded related to all open tax years. As a result of the Tax Cuts and Jobs Act (TCJA), the Company was effectively taxed on all of its previously unremitted foreign earnings. The TCJA also enacts a territorial tax system that allows, for the most part, tax-free repatriation of foreign earnings. The Company still considers the earnings of its foreign subsidiaries to be permanently reinvested, but, if repatriation were to occur, the Company would be required to accrue U.S. taxes, if any, and remit applicable withholding taxes as appropriate. The Company has unremitted earnings and profits of $607.6 and $927.4 that are permanently reinvested in its foreign subsidiaries as of December 31, 2023, and 2022, respectively. A determination of the amount of the unrecognized deferred tax liability related to these undistributed earnings is not practicable due to the complexity and variety of assumptions necessary based on the manner in which the undistributed earnings would be repatriated.

STOCK COMPENSATION PLANS

STOCK COMPENSATION PLANS	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	The following table shows the weighted average grant-date fair values of options issued during the respective year and the weighted average assumptions that the Company used to develop the fair value estimates: 2023 2022 2021 Fair value per option $ 72.27 $ 68.35 $ 55.75 Weighted average expected life (in years) 6.0 6.0 6.0 Risk free interest rate 3.4 % 2.0 % 0.6 % Expected volatility 29.8 % 28.6 % 28.6 % Expected dividend yield 1.4 % 0.9 % N/A The Company uses the Black-Scholes model to calculate the fair value of the employee’s purchase right. The fair value of the employee’s purchase right and the assumptions used in its calculation are as follows: 2023 2022 2021 Fair value of the employee’s purchase right $ 49.19 $ 62.50 $ 59.89 Valuation assumptions Risk free interest rate 5.0% 1.3% 0.1% Expected volatility 0.3 0.3 0.3 Expected dividend yield 1.4% 0.9% —%
STOCK COMPENSATION PLANS	STOCK COMPENSATION PLANS Stock Incentive Plans In 2016, the shareholders approved the Laboratory Corporation of America Holdings 2016 Omnibus Incentive Plan (the Plan). Under the Plan, as of December 31, 2023, there are 9.4 shares authorized for issuance and 3.5 shares available for grant. Stock Options The following table summarizes grants of non-qualified options made by the Company to officers, key employees, and non-employee directors under all plans. Stock options are generally granted at an exercise price equal to or greater than the fair market price per share on the date of grant. Also, for each grant, options vest ratably over a period of three years on the anniversaries of the grant date, and have a contractual exercise period of 10 years subject to their earlier expiration or termination. Changes in options outstanding under the plans for the period indicated were as follows: Number of Weighted-Average Weighted-Average Aggregate Outstanding at December 31, 2022 0.5 169.31 Granted 0.1 219.83 Outstanding at December 31, 2023 0.6 174.45 6.0 $ 32.2 Exercisable at December 31, 2023 0.5 159.05 5.4 $ 31.3 The aggregate intrinsic value in the table above represents the total pre-tax intrinsic value (the difference between the Company’s closing stock price on the last trading day of 2023 and the exercise price, multiplied by the number of in-the-money options) that would have been received by the option holders had all option holders exercised their options on December 31, 2023. Cash received by the Company from option exercises, the actual tax benefit realized for the tax deductions and the aggregate intrinsic value of options exercised from option exercises under all share-based payment arrangements during the years ended December 31, 2023, 2022, and 2021 were as follows: 2023 2022 2021 Cash received by the Company $ 2.9 $ 7.1 $ 6.8 Tax benefits realized $ 0.7 $ 1.8 $ 1.7 Aggregate intrinsic value $ 0.7 $ 8.2 $ 13.4 The following table shows the weighted average grant-date fair values of options issued during the respective year and the weighted average assumptions that the Company used to develop the fair value estimates: 2023 2022 2021 Fair value per option $ 72.27 $ 68.35 $ 55.75 Weighted average expected life (in years) 6.0 6.0 6.0 Risk free interest rate 3.4 % 2.0 % 0.6 % Expected volatility 29.8 % 28.6 % 28.6 % Expected dividend yield 1.4 % 0.9 % N/A The Black Scholes model incorporates assumptions to value stock-based awards. The risk-free interest rate for periods within the contractual life of the option is based on a zero-coupon U.S. government instrument over the contractual term of the equity instrument. Expected volatility of the Company’s stock is based on historical volatility of the Company’s stock. The Company estimates expected option terms through an analysis of actual, historical post-vesting exercise, cancellation and expiration behavior by employees and projected post-vesting activity of outstanding options. Groups of employees and non-employee directors that have similar exercise behavior with regard to option exercise timing and forfeiture rates are considered separately for valuation purposes. For 2023, 2022 and 2021, expense related to the Company’s stock option plan totaled $3.8, $4.3 and $3.6, respectively, and is included in selling, general and administrative expenses. Restricted Stock, Restricted Stock Units and Performance Shares The Company grants restricted stock, restricted stock units, and performance shares (non-vested shares) to officers and key employees and grants restricted stock and restricted stock units to non-employee directors. Restricted stock and units typically vest annually in equal one-third increments beginning on the first anniversary of the grant. A performance share grant in 2021 represents a three-year award opportunity for the period 2021-2023, and if earned, vests fully (to the extent earned) in the first quarter of 2024. A performance share grant in 2022 represents a three-year award opportunity for the period of 2022-2024 and, if earned, vests fully (to the extent earned) in the first quarter of 2025. A performance share grant in 2023 represents a three-year award opportunity for the period of 2023-2025 and, if earned, vests fully (to the extent earned) in the first quarter of 2026. Performance share awards are subject to certain earnings per share, revenue, and total shareholder return targets, the achievement of which may increase or decrease the number of shares which the grantee earns and therefore receives upon vesting. Unearned restricted stock and performance share compensation is amortized to expense, when probable, over the applicable vesting periods. For 2023, 2022, and 2021, total restricted stock, restricted stock unit, and performance share compensation expense was $111.1, $97.7 and $114.6, respectively. The following table shows a summary of non-vested shares for the year ended December 31, 2023: Number of Weighted-Average Non-vested at January 1, 2023 1.1 $ 231.30 Granted 0.5 224.11 Vested (0.5) 208.71 Canceled (0.1) 235.27 Non-vested at December 31, 2023 1.0 $ 248.41 Unrecognized Compensation Cost As of December 31, 2023, there was $83.0 of total unrecognized compensation cost related to non-vested stock options, restricted stock, restricted stock unit and performance share-based compensation arrangements granted under the Company's stock incentive plans. That cost is expected to be recognized over a weighted average period of 1.9 years and will be included in cost of revenues and selling, general and administrative expenses. Employee Stock Purchase Plan Under the 2016 Employee Stock Purchase Plan, the Company is authorized to issue 1.8 shares of Common Stock. The plan permits substantially all U.S., Canada and United Kingdom employees to purchase a limited number of shares of Company stock at 85% of market value. The Company issues shares to participating employees semi-annually in January and July of each year, although due to the spin-off of Fortrea shares for the first offering period were issued in May of 2023. Approximately 0.3, 0.2 and 0.2 shares were purchased by eligible employees in 2023, 2022 and 2021, respectively. For 2023, 2022 and 2021, expense related to the Company’s employee stock purchase plan was $13.8, $14.8 and $14.6, respectively. The Company uses the Black-Scholes model to calculate the fair value of the employee’s purchase right. The fair value of the employee’s purchase right and the assumptions used in its calculation are as follows: 2023 2022 2021 Fair value of the employee’s purchase right $ 49.19 $ 62.50 $ 59.89 Valuation assumptions Risk free interest rate 5.0% 1.3% 0.1% Expected volatility 0.3 0.3 0.3 Expected dividend yield 1.4% 0.9% —%

COMMITMENTS AND CONTINGENT LIAB

COMMITMENTS AND CONTINGENT LIABILITIES	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENT LIABILITIES	COMMITMENTS AND CONTINGENCIES The Company is involved from time to time in various claims and legal actions, including arbitrations, class actions, and other litigation (including those described in more detail below), arising in the ordinary course of business. Some of these actions involve claims that are substantial in amount. These matters include, but are not limited to, intellectual property disputes, commercial and contract disputes, professional liability claims, employee-related matters, transaction-related disputes, securities and corporate law matters, and inquiries, including subpoenas and other civil investigative demands, from governmental agencies, Medicare or Medicaid payers and MCOs reviewing billing practices or requesting comment on allegations of billing irregularities that are brought to their attention through billing audits or third parties. The Company receives civil investigative demands or other inquiries from various governmental bodies in the ordinary course of its business. Such inquiries can relate to the Company or other parties, including physicians and other health care providers. The Company works cooperatively to respond to appropriate requests for information. The Company also is named from time to time in suits brought under the qui tam provisions of the False Claims Act and comparable state laws. These suits typically allege that the Company has made false statements and/or certifications in connection with claims for payment from U.S. federal or state healthcare programs. The suits may remain under seal (hence, unknown to the Company) for some time while the government decides whether to intervene on behalf of the qui tam plaintiff. Such claims are an inevitable part of doing business in the healthcare field today. The Company believes that it is in compliance in all material respects with all statutes, regulations, and other requirements applicable to its commercial laboratory operations and biopharma laboratory services. These industries are, however, subject to extensive regulation, and the courts have not interpreted many of the applicable statutes and regulations. Therefore, the applicable statutes and regulations could be interpreted or applied by a prosecutorial, regulatory, or judicial authority in a manner that would adversely affect the Company. Potential sanctions for violation of these statutes and regulations include significant civil and criminal penalties, fines, the loss of various licenses, certificates and authorizations, additional liabilities from third-party claims, and/or exclusion from participation in government programs. Many of the current claims and legal actions against the Company are in preliminary stages, and many of these cases seek an indeterminate amount of damages. The Company records an aggregate legal reserve, which is determined using calculations based on historical loss rates and assessment of trends experienced in settlements and defense costs. In accordance with FASB Accounting Standards Codification Topic 450 “Contingencies,” the Company establishes reserves for judicial, regulatory, and arbitration matters outside the aggregate legal reserve if and when those matters present loss contingencies that are both probable and reasonably estimable and would exceed the aggregate legal reserve. When loss contingencies are not both probable and reasonably estimable, the Company does not establish separate reserves. The Company is unable to estimate a range of reasonably probable loss for the proceedings described in more detail below in which damages either have not been specified or, in the Company's judgment, are unsupported and/or exaggerated and (i) the proceedings are in early stages, (ii) there is uncertainty as to the outcome of pending appeals or motions, (iii) there are significant factual issues to be resolved, and/or (iv) there are novel legal issues to be presented. For these proceedings, however, the Company does not believe, based on currently available information, that the adverse outcomes are probable and reasonably estimable, and it does not believe they will have a material adverse effect on the Company's financial statements. The Company has received various subpoenas and other civil investigative demands related to Medicaid billing. In October 2009, the Company received a subpoena from the State of Michigan Department of Attorney General seeking documents related to its billing to Michigan Medicaid. The Company cooperated with this request. In October 2013, the Company received a Civil Investigative Demand from the State of Texas Office of the Attorney General requesting documents related to its billing to Texas Medicaid. The Company cooperated with this request. On October 5, 2018, the Company received a second Civil Investigative Demand from the State of Texas Office of the Attorney General requesting documents related to its billing to Texas Medicaid. The Company cooperated with this request. On January 26, 2021, the Company was notified that a qui tam Petition was pending under seal in the District Court, 250th Judicial District, Travis County, Texas, and that the State of Texas has intervened. On April 14, 2021, the Petition was unsealed. The Petition alleges that the Company submitted claims for reimbursement to Texas Medicaid that were higher than permitted under Texas Medicaid’s alleged “best price” regulations, and that the Company offered remuneration to Texas health care providers in the form of discounted pricing for certain laboratory testing services in exchange for the providers’ referral of Texas Medicaid business to the Company. The Petition seeks actual and double damages and civil penalties, as well as recovery of costs, attorney's fees, and legal expenses. On August 1, 2022, the District Court entered an order granting the Company's Motion for Partial Summary Judgment with respect to the claim that the Company submitted claims for reimbursement to Texas Medicaid that were higher than permitted under Texas Medicaid's alleged “best price” regulations. Plaintiffs filed a Notice of Non-Suit and Motion for Entry of Final Judgment and, on November 11, 2022, the court entered a Judgment. Plaintiffs filed a Notice of Appeal with respect to the court's order granting the Company's Motion for Partial Summary Judgment, referenced above. The Company will vigorously defend the lawsuit. On August 31, 2015, the Company was served with a putative class action lawsuit, Patty Davis v. Laboratory Corporation of America, et al. , filed in the Circuit Court of the Thirteenth Judicial Circuit for Hillsborough County, Florida. The complaint alleges that the Company violated the Florida Consumer Collection Practices Act by billing patients who were collecting benefits under the Workers' Compensation Statutes. The lawsuit seeks injunctive relief and actual and statutory damages, as well as recovery of attorney's fees and legal expenses. In April 2017, the Circuit Court granted the Company’s Motion for Judgment on the Pleadings. The Plaintiff appealed the Circuit Court’s ruling to the Florida Second District Court of Appeal. On October 16, 2019, the Florida Second District Court of Appeal reversed the Circuit Court’s dismissal, but certified a controlling issue of Florida law to the Florida Supreme Court. On February 17, 2020, the Florida Supreme Court accepted jurisdiction of the lawsuit. The court held oral arguments on December 9, 2020. On May 26, 2022, the Florida Supreme Court issued an opinion approving the result of the Florida Second District Court of Appeal in favor of the Plaintiff. The Company will vigorously defend the lawsuit. On December 29, 2021, the Company was served with a putative class action lawsuit, Nathaniel J. Nolan, et al. v. Laboratory Corporation of America Holdings , filed in the U.S. District Court for the Middle District of North Carolina. The complaint alleges that the Company's patient acknowledgement of estimated financial responsibility form is misleading. The lawsuit seeks a declaratory judgment under the consumer protection laws of Nevada and Florida that the form is materially misleading and deceptive, an injunction barring the use of the form, damages on behalf of an alleged class, and attorney's fees and expenses. On February 28, 2022, the Company filed a Motion to Dismiss all claims. On February 13, 2023, the court entered an order granting the Company's Motion to Dismiss. On March 13, 2023, Plaintiffs filed a Notice of Appeal. The Company will vigorously defend the Nolan lawsuit. On April 1, 2019, Covance Research Products was served with a Grand Jury Subpoena issued by the Department of Justice (DOJ) in Miami, Florida requiring the production of documents related to the importation into the United States of live non-human primate shipments originating from or transiting through China, Cambodia, and/or Vietnam from April 1, 2014 through March 28, 2019. The Company is cooperating with the DOJ. On May 14, 2019, Retrieval-Masters Creditors Bureau, Inc. d/b/a American Medical Collection Agency (AMCA), an external collection agency, notified the Company about a security incident AMCA experienced that may have involved certain personal information about some of the Company’s patients (the AMCA Incident). The Company referred patient balances to AMCA only when direct collection efforts were unsuccessful. The Company’s systems were not impacted by the AMCA Incident. Upon learning of the AMCA Incident, the Company promptly stopped sending new collection requests to AMCA and stopped AMCA from continuing to work on any pending collection requests from the Company. AMCA informed the Company that it appeared that an unauthorized user had access to AMCA’s system between August 1, 2018, and March 30, 2019, and that AMCA could not rule out the possibility that personal information on AMCA’s system was at risk during that time period. Information on AMCA’s affected system from the Company may have included name, address, and balance information for the patient and person responsible for payment, along with the patient’s phone number, date of birth, referring physician, and date of service. The Company was later informed by AMCA that health insurance information may have been included for some individuals, and because some insurance carriers utilize the Social Security Number as a subscriber identification number, the Social Security Number for some individuals may also have been affected. No ordered tests, laboratory test results, or diagnostic information from the Company were in the AMCA affected system. The Company notified individuals for whom it had a valid mailing address. For the individuals whose Social Security Number was affected, the notice included an offer to enroll in credit monitoring and identity protection services that was provided free of charge for 24 months. Twenty-three putative class action lawsuits were filed against the Company related to the AMCA Incident in various U.S. District Courts. Numerous similar lawsuits have been filed against other health care providers who used AMCA. These lawsuits were consolidated into a multidistrict litigation in the District of New Jersey. On November 15, 2019, the Plaintiffs filed a Consolidated Class Action Complaint in the U.S. District Court of New Jersey. The consolidated Complaint generally alleged that the Company did not adequately protect its patients’ data and failed to timely notify those patients of the AMCA Incident. The Complaint asserted various causes of action, including but not limited to negligence, breach of implied contract, unjust enrichment, and the violation of state data protection statutes. The Complaint sought damages on behalf of a class of all affected Company customers. On January 22, 2020, the Company filed Motions to Dismiss all claims. On December 16, 2021, the court granted in part and denied in part the Company's Motion to Dismiss. On March 31, 2022, the Plaintiffs filed an Amended Complaint alleging claims for negligence, negligence per se , breach of confidence, invasion of privacy, and various state statutory claims, including a claim under the California Confidentiality of Medical Information Act. The Company filed a Motion to Dismiss certain claims of the Amended Complaint. On May 5, 2023, the court granted in part and denied in part the Company's Motion to Dismiss. The Company will vigorously defend the remaining claims in the multi-district litigation. The Company was served with a shareholder derivative lawsuit, Raymond Eugenio, Derivatively on Behalf of Nominal Defendant, Laboratory Corporation of America Holdings v. Lance Berberian, et al. , filed in the Court of Chancery of the State of Delaware on April 23, 2020. The complaint asserts derivative claims on the Company’s behalf against the Company’s board of directors and certain executive officers. The complaint generally alleges that the defendants failed to ensure that the Company utilized proper cybersecurity safeguards and failed to implement a sufficient response to data security incidents, including the AMCA Incident. The complaint asserts derivative claims for breach of fiduciary duty and seeks relief including damages, certain disclosures, and certain changes to the Company’s internal governance practices. On June 2, 2020, the Company filed a Motion to Stay the lawsuit due to its overlap with the multi-district litigation referenced above. On July 2, 2020, the Company filed a Motion to Dismiss. On July 14, 2020, the court entered an order staying the lawsuit pending the resolution of the multi-district litigation. The lawsuit will be vigorously defended. Certain governmental entities have requested information from the Company related to the AMCA Incident. The Company received a request for information from the Office for Civil Rights (OCR) of the Department of Health and Human Services. On April 28, 2020, OCR notified the Company of the closure of its inquiry. The Company has also received requests from a multi-state group of state Attorneys General and is cooperating with these requests for information. On January 31, 2020, the Company was served with a putative class action lawsuit, Luke Davis and Julian Vargas, et al. v. Laboratory Corporation of America Holdings , filed in the U.S. District Court for the Central District of California. The lawsuit alleges that visually impaired patients are unable to use the Company's touchscreen kiosks at Company patient service centers in violation of the Americans with Disabilities Act and similar California statutes. The lawsuit seeks statutory damages, injunctive relief, and attorney's fees and costs. On March 20, 2020, the Company filed a Motion to Dismiss Plaintiffs' Complaint and to Strike Class Allegations. In August 2020, the Plaintiffs filed an Amended Complaint. On April 26, 2021, the Plaintiffs and the Company each filed Motions for Summary Judgment and the Plaintiffs filed a Motion for Class Certification. On May 23, 2022, the court entered an order granting Plaintiffs’ Motion for Class Certification. On June 6, 2022, the Company filed a Petition for Permission to Appeal the Order Granting Class Certification with the U.S. Court of Appeals for the Ninth Circuit. On September 22, 2022, the Ninth Circuit granted the Company's Petition for Permission to Appeal the Order Granting Class Certification. On February 8, 2024, the Ninth Circuit affirmed the trial court’s decision to certify both a California damages class and a nationwide injunctive class. The Company will vigorously seek rehearing and further appeal if necessary. On October 16, 2020, Ravgen Inc. filed a patent infringement lawsuit, Ravgen Inc. v. Laboratory Corporation of America Holdings , in the U.S. District Court for the Western District of Texas, alleging infringement of two Ravgen-owned U.S. patents. The lawsuit seeks monetary damages, enhancement of those damages for willfulness, and recovery of attorney’s fees and costs. On September 28, 2022, a jury rendered a verdict in favor of the Plaintiff on the remaining patent at issue, finding that the Company willfully infringed Ravgen's patent, and awarded damages of $272.0. Plaintiff filed post-trial motions seeking enhanced damages of up to $817.0 based on the finding of willfulness, as well as attorney's fees and costs. On May 12, 2023, the court issued an order granting Plaintiff's motion in part and awarding damages of $100.0. The Company strongly disagrees with the verdict, based on a number of legal factors, and will vigorously defend the lawsuit through the appeal process. On June 4, 2021, the Company also instituted proceedings before the Patent Trial and Appeal Board of the U.S. Patent and Trademark Office challenging the validity of the Ravgen patent at issue in the trial. In November 2022, the Patent Trial and Appeal Board issued a decision upholding the validity of the Ravgen patent, and the Company has filed an appeal of this decision. On May 14, 2020, the Company was served with a putative class action lawsuit, Jose Bermejo v. Laboratory Corporation of America (Bermejo I) filed in the Superior Court of California, County of Los Angeles Central District, alleging that certain non-exempt California-based employees were not properly compensated for driving time or properly paid wages upon termination of employment. The Plaintiff asserts these actions violate various California Labor Code provisions and Section 17200 of the Business and Professional Code. The lawsuit seeks monetary damages, civil penalties, and recovery of attorney’s fees and costs. On June 15, 2020, the lawsuit was removed to the U.S. District Court for the Central District of California. On June 16, 2020, the Company was served with a Private Attorney General Act lawsuit by the same plaintiff in Jose Bermejo v. Laboratory Corporation of America (Bermejo II), filed in the Superior Court of California, County of Los Angeles Central District, alleging that certain Company practices violated California Labor Code penalty provisions related to unpaid and minimum wages, unpaid overtime, unpaid meal and rest break premiums, untimely payment of wages following separation of employment, failure to maintain accurate pay records, and non-reimbursement of business expenses. The second lawsuit seeks to recover civil penalties and recovery of attorney's fees and costs. On October 28, 2020, the court issued an order staying proceedings in Bermejo II pending resolution of Bermejo I . The second lawsuit seeks to recover civil penalties and recovery of attorney's fees and costs. On February 24, 2022, the parties entered into a Memorandum of Understanding of the terms of a settlement of the Bermejo I and Bermejo II lawsuits. The court granted preliminary approval of the parties' settlement agreement of the Bermejo I lawsuit on March 17, 2023, and of the Bermejo II lawsuit on November 29, 2023. The settlement funds for the Bermejo I and Bermejo II settlements have been transferred to a claims administrator for processing. Once the claims administration is completed, the parties will seek final settlement approval from the Court. On June 14, 2021, a single plaintiff filed a Private Attorney General Act lawsuit, Becker v. Laboratory Corporation of America , in the Superior Court of California, County of Orange, alleging various violations of the California Labor Code, including that the Plaintiff was not properly compensated for work and overtime hours, not properly paid meal and rest break premiums, not reimbursed for certain business-related expenses, and received inaccurate wage statements. The lawsuit seeks monetary damages, civil penalties, and recovery of attorney’s fees and costs. A settlement of the Bermejo I and Bermejo II lawsuits, if approved by the court, will resolve the Becker lawsuit. On November 23, 2021, the Company was served with a single plaintiff Private Attorney General Act lawsuit, Poole v. Laboratory Corporation of America , filed in the Superior Court of California, County of Kern, alleging various violations of the California Labor Code, including that Plaintiff was not properly paid wages owed, not properly paid meal and rest break premiums, not reimbursed for certain business related expenses, and other allegations including the untimely payment of wages and receipt of inaccurate wage statements. The lawsuit seeks monetary damages, civil penalties, and recovery of attorney's fees and costs. The case was removed to the U.S. District Court for the Eastern District of California. A settlement of the Bermejo I and Bermejo II lawsuits, if approved by the court, will resolve the portion of the Poole lawsuit relating to service representatives and senior service representatives. On October 5, 2020, the Company was served with a putative class action lawsuit, Williams v. LabCorp Employer Services, Inc. et al. , filed in the Superior Court of California, County of Los Angeles, alleging that certain non-exempt California-based employees were not properly compensated for work and overtime hours, not properly paid meal and rest break premiums, not reimbursed for certain business-related expenses, not properly paid for driving or wait times, and received inaccurate wage statements. The Plaintiff also asserts claims for unfair competition under Section 17200 of the Business and Professional Code. On November 4, 2020, the lawsuit was removed to the U.S. District Court for the Central District of California. The lawsuit seeks monetary damages, liquidated damages, civil penalties, and recovery of attorney's fees and costs. On June 24, 2021, the District Court remanded the case to the Superior Court of California, County of Los Angeles on the grounds that potential damages did not meet the Class Action Fairness Act (CAFA), 28 U.S.C. § 1332(d), jurisdictional threshold. The parties entered into a settlement agreement dated September 9, 2022. On December 13, 2023, the Court granted preliminary approval of the settlement. The settlement funds have been transferred to a claims administrator for processing. Once the claims administration is completed, the parties will seek final settlement approval from the Court. On June 7, 2023, the Company was served with a putative class action lawsuit, Connie Howard, Yadira Yazmin Hernandez, and Deborah Reynolds, et al. v. Laboratory Corporation of America, Laboratory Corporation of America Holdings, and Meta Platforms, Inc. , filed in the U.S. District Court for the Northern District of California, alleging that the Company’s website includes a tracking code created by Meta, known as the Meta Pixel, that sent information related to Plaintiffs and their online activities to Meta. Plaintiffs assert claims against the Company under California and Pennsylvania law and seek to represent classes of all persons in California, or in Pennsylvania, who allegedly entered search terms into the Company’s website and who used Facebook during a time that Plaintiffs allege the Meta Pixel was active on the Company’s website. Plaintiffs seek an injunction, damages, attorneys’ fees, and costs. On August 23, 2023, the Company filed a Motion to Dismiss. On September 5, 2023, the lawsuit was transferred to the U.S. District Court for the Middle District of North Carolina. On September 9, 2023, Plaintiffs filed an Amended Complaint. Among other things, the Amended Complaint contains allegations that in addition to the Meta Pixel, the Company's website uses Google Analytics and other online tracking technologies. On October 11, 2023, the Company filed a Motion to Dismiss the Amended Complaint. The Company will vigorously defend the lawsuit. On August 14, 2020, the Company was served with a Subpoena Duces Tecum issued by the State of Colorado Office of the Attorney General requiring the production of documents related to urine drug testing in all states. The Company is cooperating with this request. On February 7, 2022, the Company was served with a Subpoena Duces Tecum issued by the DOJ in Camden, New Jersey requiring the production of documents related to non-invasive prenatal screening tests. The Company is cooperating with the DOJ. On June 27, 2022, the Company was served with a Subpoena Duces Tecum issued by the DOJ in Boston, Massachusetts requiring the production of documents related to urine drug testing. The Company is cooperating with the DOJ. In April 2023, the Company received Civil Investigative Demands issued by the DOJ in Washington, D.C. requiring the production of information related to the Medicare billing rule regarding reimbursement for laboratory testing performed for hospital patients. The Company is cooperating with the DOJ . On February 13, 2024, a putative class action lawsuit, Michael Wiggins and Teri Stevens v. Laboratory Corporation of America Holdings , was filed in the U.S. District Court for the Eastern District of Pennsylvania, alleging that the Company’s website includes a computer code created by Google that sent information to Google related to Plaintiffs and their online activities. Plaintiffs assert statutory and common law claims against the Company and seek to represent a class of all persons whose protected health information was allegedly shared with Google from the Company's website before March 8, 2023. Plaintiffs seek an injunction, damages, attorneys’ fees, and costs. The Company will vigorously defend the lawsuit. There are various other pending legal proceedings involving the Company including, but not limited to, additional employment-related lawsuits, professional liability lawsuits, and commercial lawsuits. While it is not feasible to predict the outcome of such proceedings, in the opinion of the Company, the likelihood of loss is remote and any reasonably possible loss associated with the resolution of such proceedings is not expected to be material to the Company’s financial condition, results of operations, or cash flows, either individually or in the aggregate. Under the Company's present insurance programs, coverage is obtained for catastrophic exposure as well as those risks required to be insured by law or contract. The Company is responsible for the uninsured portion of losses related primarily to general, professional and vehicle liability, certain medical costs and workers' compensation. The self-insured retentions are on a per-occurrence basis without any aggregate annual limit. Provisions for losses expected under these programs are recorded based upon the Company's estimates of the aggregated liability of claims incurred.

PENSION AND POSTRETIREMENT PLAN

PENSION AND POSTRETIREMENT PLANS	12 Months Ended
	Dec. 31, 2023
Postemployment Benefits [Abstract]
PENSION AND POSTRETIREMENT PLANS	PENSION AND POSTRETIREMENT PLANS Defined Contribution Retirement Plans The Company has various U.S. defined contribution retirement plans (401K Plans). Under these 401K Plans, employees can contribute a portion of their salary to the plan and the Company makes minimum non-elective contributions, discretionary contributions, and matching contributions, depending on the terms of the specific plan. On January 1, 2021, all of the 401K Plans were modified to provide for 100% match of employee contributions up to 5% of their salary. Total expense, for the years ended December 31, 2023, 2022, and 2021, was $167.6, $128.2 and $111.2, respectively. Defined Benefit Pension Plans The Company sponsors both funded and unfunded defined benefit pension plans which provide benefits based on various criteria such as years of service and salary. The Company maintained two plans in the United States, two plans in the United Kingdom and one in Germany. The two plans in the United States (U.S. Plans) were closed to new entrants and the accrual of service credits at the end of 2009. The U.K. pension plan was closed to new entrants and the accrual of service credits for one plan as of December 31, 2002, and the accrual of service credits for the other plan as of December 31, 2019. The German plan was closed to new entrants on December 31, 2009 but participants continue to accrue service credits. The U.K. and German plans are aggregated for disclosure as the Non-U.S. Plans. Net Periodic Benefit Costs The components of the net periodic benefit costs for the defined benefit pension plans are as follows: U. S. Plans Non-U.S. Plans Year ended December 31, 2023 2022 2021 2023 2022 2021 Service cost for benefits earned $ 3.9 $ 2.8 $ 3.9 1.4 2.4 2.2 Interest cost on benefit obligation 12.3 9.1 8.3 15.2 9.1 7.2 Expected return on plan assets (11.6) (12.9) (17.3) (16.7) (15.8) (14.3) Net amortization and deferral 4.5 4.6 10.0 0.1 0.8 1.9 Settlements 10.9 4.1 3.7 — (1.1) — Defined-benefit plan costs $ 20.0 $ 7.7 $ 8.6 — (4.6) (3.0) Service costs are the only component of net periodic benefit costs recorded within Operating income. For the year ended December 31, 2023, the Company recognized a partial plan settlement charge of $10.9 as a component of Other, net. The amounts recognized in accumulated other comprehensive earnings are as follows: U. S. Plans Non-U.S. Plans Year ended December 31, 2023 2022 2023 2022 Net actuarial loss in accumulated other comprehensive earnings $ 47.2 $ 60.9 $ 19.1 $ 22.6 Change in Projected Benefit Obligation The change in the projected benefit obligation as of December 31, 2023, and December 31, 2022, is as follows: U.S. Plans Non-U.S. Plans Year Ended December 31, 2023 2022 2023 2022 Balance at beginning of the year $ 259.5 $ 333.3 $ 319.9 $ 569.8 Service cost 3.9 2.8 1.4 2.4 Interest cost 12.3 9.1 15.2 9.1 Actuarial (gain) loss 11.7 (58.4) 7.0 (187.7) Benefits and administrative expenses paid (55.5) (27.3) (14.2) (19.5) Foreign currency exchange rate changes — — 16.4 (54.2) Balance at end of the year $ 231.9 $ 259.5 $ 345.7 $ 319.9 The accumulated benefit obligation as of December 31, 2023 and 2022 was $231.9 and $259.5, respectively for the U.S. Plans and $345.7 and $319.9, respectively for the Non-U.S. Plans. Change in Fair Value of Plan Assets The change in plan assets as of December 31, 2023, and December 31, 2022, is as follows: U.S. Plans Non-U.S. Plans Year Ended December 31, 2023 2022 2023 2022 Balances at beginning of the year $ 226.8 $ 299.9 $ 301.2 $ 485.2 Company contributions — — 14.1 13.8 Actual return on plan assets 21.6 (48.2) 18.0 (134.7) Benefits and administrative expenses paid (53.1) (24.9) (13.7) (14.9) Foreign currency exchange rate changes — — 16.3 (48.2) Fair value of plan assets at end of year $ 195.3 $ 226.8 $ 335.9 $ 301.2 Change in Funded Status and Reconciliation of Amounts Recorded in the Balance Sheet The change in the funded status of the plan and a reconciliation of such funded status to the amounts reported in the consolidated balance sheet as of December 31, 2023, and December 31, 2022, is as follows: U.S. Plans Non-U.S. Plans Year Ended December 31, 2023 2022 2023 2022 Funded status $ 36.6 $ 32.7 $ 9.8 $ 22.8 Recorded as: Other assets $ — $ 2.2 $ 21.5 $ 7.0 Accrued expenses and other 2.5 2.4 0.7 0.6 Other liabilities 34.1 32.5 30.6 29.2 Assumptions Weighted average assumptions used to determine net periodic benefit costs are as follows: U. S. Plans Non-U.S. Plans Year ended December 31, 2023 2022 2021 2023 2022 2021 Discount rate 5.5 % 2.8 % 2.4 % 4.0 % 2.1 % 1.1 % Salary increases N/A N/A N/A 2.0 % 2.0 % 2.0 % Expected long term rate of return 6.0 % 4.5 % 6.0 % 5.3 % 3.6 % 3.1 % Cash balance interest credit rate 4.0 % 4.0 % 4.0 % N/A N/A N/A A one percentage point decrease or increase in the discount rate would have resulted in a respective increase or decrease in 2023 retirement plan expense of $0.4 for the U.S. Plans. A one percentage point decrease or increase in the discount rate would have resulted in a respective increase or decrease in 2023 retirement plan expense of $0.7 for the Non-U.S. Plans. Weighted average assumptions used to determine net periodic benefit obligations are as follows: U. S. Plans Non-U.S. Plans Year ended December 31, 2023 2022 2023 2022 Discount rate 5.1 % 5.5 % 4.3 % 4.8 % Salary increases N/A N/A 2.0 % 2.0 % The discount rate is determined using the weighted-average yields on high-quality fixed income securities that have maturities consistent with the timing of benefit payments. Lower discount rates increase the size of the benefit obligation and generally increase pension expense in the following year; higher discount rates reduce the size of the benefit obligation and generally reduce subsequent-year pension expense. The expected return on plan assets is the estimated long-term rate of return that will be earned on the investments used to fund the pension obligations. To determine this rate, the Company considers the composition of plan investments, historical returns earned, and expectations about the future. Actual asset over/under performance compared to expected returns will respectively decrease/increase unrecognized loss. The change in the unrecognized loss will change amortization cost in upcoming periods. A one percentage point increase or decrease in the expected return on plan assets would have resulted in a corresponding change in 2023 pension expense of $2.2 for the U.S. Plans. A one percentage point increase or decrease in the expected return on plan assets would have resulted in a corresponding change in 2023 pension expense of $3.1 for the Non-U.S. Plans. The salary increase assumptions are used to estimate the annual rate at which pay of plan participants will grow. If the rate of growth assumed increases, the size of the pension obligations will increase, as will the amount recorded in Accumulated other comprehensive income (loss) in the Company's Consolidated Statement of Financial Position and amortized into earnings in subsequent periods. The Company evaluates other assumptions periodically, such as retirement age, mortality and turnover, and updates them as necessary to reflect the Company's actual experience and expectations for the future. Differences between actual results and assumptions utilized are recorded in Accumulated other comprehensive income each period. These differences are amortized into earnings over the remaining average future service of active participating employees or the expected life of inactive participants, as applicable. Plan Assets The fair values of the assets at December 31, 2023, and 2022, by asset category are as follows: Asset Category Level of Valuation Input Fair Value Investments valued using NAV per share Total U.S Plans Cash and cash equivalents Level 1 $ 3.3 $ — $ 3.3 U.S. equity index funds — 27.3 27.3 International equity index funds — 11.4 11.4 Real estate — 4.0 4.0 General bond index funds — 149.3 149.3 Total fair value $ 3.3 $ 192.0 $ 195.3 Non U.S. Plans Cash and cash equivalents Level 1 $ 46.2 $ — $ 46.2 Annuities Level 3 52.8 — 52.8 Pooled investment funds — 236.9 236.9 Total fair value $ 99.0 $ 236.9 $ 335.9 Asset Category Level of Valuation Input Fair Value Investments valued using NAV per share Total U.S Plans Cash and cash equivalents Level 1 $ 3.9 $ — $ 3.9 U.S. equity index funds — 39.6 39.6 International equity index funds — 17.0 17.0 Real estate index fund — 5.0 5.0 General bond index funds — 161.3 161.3 Total fair value $ 3.9 $ 222.9 $ 226.8 Non U.S. Plans Cash and cash equivalents Level 1 $ 3.0 $ — $ 3.0 Annuities Level 3 50.1 — 50.1 Pooled investment funds — 248.1 248.1 Total fair value $ 53.1 $ 248.1 $ 301.2 The fair market value of index funds and pooled investment funds are valued using the net asset value (NAV) unit price provided by the fund administrator. The NAV is based on the value of the underlying assets owned by the fund. The fair value of annuity investments are based on discounted cash flow techniques using unobservable valuation inputs such as discount rates and actuarial mortality tables. Fair Value Measurement of Level 3 Pension Assets Annuities Balance at January 1, 2022 $ 81.3 Actual return on plan assets (31.2) Balance at December 31, 2022 50.1 Actual return on plan assets 2.7 Balance at December 31, 2023 $ 52.8 Investment Policies Plan fiduciaries of various plans set investment policies and strategies, based on consultation with professional advisors, and oversee investment allocation, which includes selecting investment managers and setting long-term strategic targets. The primary strategic investment objectives are balancing investment risk and return and monitoring the plan’s liquidity position in order to meet the near-term benefit payment and other cash needs. Target allocation percentages are established at an asset class level by plan fiduciaries. Target allocation ranges are guidelines, not limitations, and occasionally plan fiduciaries will approve allocations above or below a target range. The weighted average asset allocation of the plan assets as of December 31, 2023, by asset category is as follows: December 31, 2023 U.S. Plans Non-U.S. Plans Equity securities 19.8 % 26.6 % Debt securities 76.4 % 40.8 % Annuities — % 15.7 % Real estate 2.1 % 3.3 % Other 1.7 % 13.7 % The weighted average target asset allocation of the plan assets is as follows: U.S. Plans Non U.S. Plans Equity securities 13.0% to 25.5 % 25.0% to 35.0% Debt securities 67.0% to 87.0 % 35.0% to 45.0% Annuities — % to — % 10.0% to 20.0% Real estate 0.5 % to 4.3 % —% to 10.0% Other — % to 5.0 % 10.0% to 25.0% Pension Funding and Cash Flows The Company expects to make approximately $16.8 in required contributions to its defined benefit pension plans during 2024. The Company targets funding the minimum required contributions but may make additional contributions into the pension plans in 2024, depending upon factors such as how the funded status of those plans change or to reduce the administrative costs of the plan. The estimated benefit payments, which were used in the calculation of projected benefit obligations, are expected to be paid as follows: U. S. Plans Non-U. S. Plans 2024 $ 21.8 $ 16.4 2025 22.4 16.2 2026 21.6 17.6 2027 20.8 18.0 2028 21.1 18.3 Years 2029 to 2033 92.2 97.8 Post-employment Retiree Health and Welfare Plan The Company sponsors a post-employment retiree health and welfare plan for the benefit of eligible employees at certain U.S. subsidiaries who retire after satisfying service and age requirements. This plan is funded on a pay-as-you-go basis and the cost of providing these benefits is shared with the retirees. Post-retirement Medical Plan The Company assumed obligations under a subsidiary's post-retirement medical plan. Coverage under this plan is restricted to a limited number of existing employees of the subsidiary. This plan is unfunded and the Company’s policy is to fund benefits as claims are incurred. The effect on operations of the post-retirement medical plan is shown in the following table: Year ended December 31, 2023 2022 2021 Interest cost on benefit obligation $ 0.2 $ 0.1 $ 0.1 Net amortization and deferral — 0.2 0.3 Post-retirement medical plan costs $ 0.2 $ 0.3 $ 0.4 Amounts included in accumulated other comprehensive earnings consist of unamortized net (income) loss of $(0.8) and $(0.2). A summary of the changes in the accumulated post-retirement benefit obligation follows: 2023 2022 Balance at January 1 $ 3.9 $ 5.2 Interest cost on benefit obligation 0.2 0.1 Actuarial loss (0.2) (0.9) Benefits paid (0.3) (0.5) Balance at December 31 $ 3.6 $ 3.9 Recorded as: Accrued expenses and other $ 0.6 $ 0.6 Other liabilities 3.0 3.3 $ 3.6 $ 3.9 The weighted-average discount rates used in the calculation of the accumulated post-retirement benefit obligation were 5.1% and 5.5% as of December 31, 2023, and 2022, respectively. The healthcare cost trend rate was removed due to the expectation of future funding to be at the same level as the previous year's funding. The following assumed benefit payments under the Company's post-retirement benefit plan, which reflect expected future service, as appropriate, and which were used in the calculation of projected benefit obligations, are expected to be paid as follows: 2024 $ 0.6 2025 0.5 2026 0.4 2027 0.3 2028 0.3 Years 2029 and thereafter 1.0 Deferred Compensation Plan The Company has Deferred Compensation Plans (DCP) under which certain of its executives may elect to defer up to 100.0% of their annual cash incentive pay and/or up to 50.0% of their annual base salary and/or eligible commissions subject to annual limits established by the U.S. government. The DCP provides executives a tax efficient strategy for retirement savings and capital accumulation without significant cost to the Company. The Company makes no contributions to the DCP. Amounts deferred by a participant are credited to a bookkeeping account maintained on behalf of each participant, which is used for measurement and determination of amounts to be paid to a participant, or his or her designated beneficiary, pursuant to the terms of the DCP. The amounts accrued under these plans were $107.4 and $96.9 at December 31, 2023, and 2022, respectively. Deferred amounts are the Company's general unsecured obligations and are subject to claims by the Company's creditors. The Company's general assets may be used to fund obligations and pay DCP benefits.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	Fair Value Measurement of Level 3 Liabilities Contingent Consideration Balance at January 1, 2022 $ 21.9 Addition 68.3 Cash payments and adjustments (12.8) Balance at December 31, 2022 77.4 Cash payments and adjustments (11.3) Balance at December 31, 2023 $ 66.1
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS The Company’s population of financial assets and liabilities subject to fair value measurements as of December 31, 2023, and 2022 were as follows: Fair Value Measurements as of December 31, 2023 Balance Sheet Classification Fair Value as of December 31, 2023 Using Fair Value Hierarchy 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 Measurements as of December 31, 2022 Balance Sheet Classification Fair Value as of December 31, 2022 Using Fair Value Hierarchy Level 1 Level 2 Level 3 Noncontrolling interest put Noncontrolling interest $ 15.0 $ — $ 15.0 $ — Cross currency swaps Other liabilities, net 45.7 — 45.7 — Interest rate swaps Other liabilities 79.7 — 79.7 — Cash surrender value of life insurance policies Other assets, net 100.7 — 100.7 — Deferred compensation liability Other liabilities 96.9 — 96.9 — Contingent consideration Accrued expenses and other/Other liabilities 77.4 — — 77.4 Fair Value Measurement of Level 3 Liabilities Contingent Consideration Balance at January 1, 2022 $ 21.9 Addition 68.3 Cash payments and adjustments (12.8) Balance at December 31, 2022 77.4 Cash payments and adjustments (11.3) Balance at December 31, 2023 $ 66.1 The Company has a noncontrolling interest put related to its Ontario subsidiary that has been classified as mezzanine equity in the Company’s consolidated balance sheets. The noncontrolling interest put is valued at its contractually determined value, which approximates fair value. During the year ended December 31, 2023, the carrying value of the noncontrolling interest put decreased by $1.0 for foreign currency translation. The Company offers certain employees the opportunity to participate in a 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 participants' 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 for which fair values are measured as Level 3 instruments. 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.

DERIVATIVE INSTRUMENTS AND HEDG

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES	12 Months Ended
	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES	DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES Interest Rate Swap During the second quarter of 2021, the Company entered into fixed-to-variable interest rate swap agreements for its 2.70% senior notes due 2031 with an aggregate notional amount of $500.0 and variable interest rates based on three-month SOFR (changed from LIBOR to SOFR during 2023) plus 1.0706%. These agreements were designated as hedges against changes in the fair value of a portion of the Company's long-term debt. Cross Currency Swaps During the fourth quarter of 2018, the Company entered into U.S. Dollar (USD) to Swiss Franc cross-currency swap agreements with an aggregate notional value of $600.0. During the second quarter of 2022, the Company terminated $300.0 of those cross-currency swap agreements and entered into new USD to Swiss Franc cross-currency swap agreements with an aggregate notional value of $300.0. The initial cross-currency swap matures in 2025 and the cross currency swap entered into in 2022 matures in 2024. These instruments are designated as a hedge against the impact of foreign exchange movements on its net investment in a Swiss subsidiary. The table below presents the fair value of derivatives on a gross basis and the balance sheet classification of those instruments: December 31, 2023 December 31, 2022 Fair Value of Derivative Fair Value of Derivative Balance Sheet Caption Asset Liability U.S. Dollar Notional Asset Liability U.S. Dollar Notional Interest rate swap Other liabilities — 69.6 500.0 — 79.7 500.0 Cross currency swaps Accrued expenses and other/Other liabilities — 109.0 600.0 — 45.7 600.0 The table below provides information regarding the location and amount of pretax (gains) losses of derivatives designated in fair value hedging relationships: Amount included in other comprehensive income Amounts reclassified to the Year Ended December 31, Year Ended December 31, 2023 2022 2021 2023 2022 2021 Cross currency swaps $ (63.3) $ (12.9) $ 7.6 $ — $ 0.9 $ —

SUPPLEMENTAL CASH FLOW INFORMAT

SUPPLEMENTAL CASH FLOW INFORMATION	12 Months Ended
	Dec. 31, 2023
Supplemental Cash Flow Information [Abstract]
SUPPLEMENTAL CASH FLOW INFORMATION	SUPPLEMENTAL CASH FLOW INFORMATION Years Ended December 31, 2023 2022 2021 Supplemental schedule of cash flow information: Cash paid during period for: Interest $ 221.5 $ 196.7 $ 194.5 Income taxes, net of refunds 206.8 474.9 964.7 Disclosure of non-cash financing and investing activities: Change in accrued property, plant and equipment 13.2 (5.6) 11.3

BUSINESS SEGMENT INFORMATION

BUSINESS SEGMENT INFORMATION	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
BUSINESS SEGMENT INFORMATION	. BUSINESS SEGMENT INFORMATION The following table is a summary of segment information for the years ended December 31, 2023, 2022, and 2021. 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. As a result of the spin-off, the Company recast the segment results to exclude the historical results of Fortrea. Additionally, the remaining operations of the Drug Development segment has been renamed as the BLS segment. Prior periods have been conformed for comparability. The Company's segment performance measure was changed to exclude the amortization of intangibles and other assets, restructuring and other charges, goodwill and other asset impairments, and certain corporate charges for items such as transaction costs, COVID-19 costs, and other special items. These changes align with how the CODM now evaluates segment performance and allocates resources. Segment asset information is not presented because it is not used by the CODM at the segment level. 2023 2022 2021 Revenues: Dx $ 9,415.1 $ 9,203.5 $ 10,363.6 BLS 2,774.2 2,697.3 2,860.7 Intercompany eliminations and other (27.7) (36.9) (88.2) Total revenues $ 12,161.6 $ 11,863.9 $ 13,136.1 Operating Earnings: Dx segment operating income $ 1,591.3 $ 2,025.5 $ 3,205.6 BLS segment operating income 396.3 389.1 501.0 Segment operating income 1,987.6 2,414.6 3,706.6 General corporate and unallocated expenses (644.1) (468.8) (404.5) Amortization of intangibles and other assets (219.8) (193.6) (229.5) Restructuring and other charges (49.1) (54.0) (24.0) Goodwill and other asset impairments (349.0) (261.7) — Total operating income $ 725.6 $ 1,436.5 $ 3,048.6 2023 2022 2021 Depreciation Dx $ 236.1 $ 227.1 $ 238.6 BLS 112.5 112.8 106.3 General corporate 8.9 3.7 2.6 Total depreciation $ 357.5 $ 343.6 $ 347.5 Geographic Distribution of property, plant and equipment, net: December 31, 2023 Dx BLS Total North America $ 1,799.2 $ 619.0 $ 2,418.2 Europe — 394.7 394.7 Other — 98.9 98.9 Total property, plant and equipment, net $ 1,799.2 $ 1,112.6 $ 2,911.8 December 31, 2022 Dx BLS Total North America $ 1,669.2 $ 639.7 $ 2,308.9 Europe — 382.4 382.4 Other — 102.7 102.7 Total property, plant and equipment, net $ 1,669.2 $ 1,124.9 $ 2,794.1

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	21. SUBSEQUENT EVENTS

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net earnings attributable to Laboratory Corporation of America Holdings	$ 418	$ 1,279.1	$ 2,377.3

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended	12 Months Ended
	Dec. 31, 2023 shares	Dec. 31, 2023 shares
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		During the fiscal quarter ended December 31, 2023, none of the Company's directors or officers informed it of the adoption, modification or termination of a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Regulation S-K, Item 408, except as described in the table below: Name and Title Date Adopted Character of Trading Agreement Aggregate Number of Shares of Common Stock to be (Sold) Purchased Pursuant to Trading Agreement Duration Mark S. Schroeder 12/7/2023 Rule 10b5-1 Trading Arrangement Up to (17,044) (1) (2) 12/6/2024 (3) President, Diagnostics Laboratories and Amy B. Summy 12/7/2023 Rule 10b5-1 Trading Arrangement Up to (4,916) (1) (2) 4/1/2024 (3) Chief Marketing Officer (1) The figure presented represents the shares to be sold on the vesting of equity awards before reduction for shares to be withheld for tax purposes. (2) Mr. Schroeder’s plan provides for the exercise of vested stock options and the associated sale of up to 2,119 shares of the Company’s Common Stock. (3) This trading arrangement permits transactions through and including the earlier to occur of (a) the completion of all sales on the respective order entry date or (b) the date listed in the table.
Rule 10b5-1 Arrangement Adopted	true
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Mark S. Schroeder [Member]
Trading Arrangements, by Individual
Name	Mark S. Schroeder
Title	President, Diagnostics Laboratories andChief Operations Officer
Adoption Date	12/7/2023
Arrangement Duration	365 days
Aggregate Available	17,044	17,044
Amy B. Summy [Member]
Trading Arrangements, by Individual
Name	Amy B. Summy
Title	Chief Marketing Officer
Adoption Date	12/7/2023
Arrangement Duration	116 days
Aggregate Available	4,916	4,916
Mark S. Schroeder, Trading Arrangement, Stock Options [Member] | Mark S. Schroeder [Member]
Trading Arrangements, by Individual
Aggregate Available	2,119	2,119

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2023 Employee
Accounting Policies [Abstract]
Basis of Financial Statement Presentation	Basis of Financial Statement Presentation Laboratory Corporation of America ® Holdings (Labcorp or the Company) (Labcorp or the Company) is a global leader of innovative and comprehensive laboratory services that provides vital information to help doctors, hospitals, pharmaceutical 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. With more than 67,000 employees, the Company serves clients in more than 100 countries. The Company reports its business in two segments, Labcorp Diagnostics (Dx) and Biopharma Laboratory Services (BLS), formerly Drug Development (DD). For further financial information about these segments, including information for each of the last three fiscal years regarding revenue, operating income, and other important information, see Note 20 Business Segment Information. In 2023, Dx and BLS contributed 77% and 23%, respectively, of revenues to the Company, and in 2022 contributed 77% and 23%, respectively. The consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries for which it exercises control. Long-term investments in affiliated companies in which the Company exercises significant influence, but which it does not control, are accounted for using the equity method. Investments in which the Company does not exercise significant influence (generally, when the Company has an investment of less than 20% and no representation on the investee's board of directors) are accounted for 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 variable interest entities or special purpose entities whose financial results are not included in the consolidated financial statements. The financial statements of the Company's 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 year. Resulting translation adjustments are included in “Accumulated other comprehensive income.” On June 30, 2023, the Company completed the separation (spin-off) of Fortrea Holdings Inc. (Fortrea), formerly the Company’s Clinical Development and Commercialization Services (CDCS) business, into a separate, publicly-traded company. All current and historical operating results of Fortrea are presented as Discontinued Operations, net of tax, in the consolidated statement of operations. As a result of the spin-off the Company recast segment results to exclude the historical results of the CDCS business for all periods presented. The remaining operations of the previously reported Drug Development segment has been renamed the Biopharma Laboratory Services segment. Additional disclosures regarding the spin-off of Fortrea are provided in Note 2 (Discontinued Operations).
Reimbursable Out of Pocket Expenses Policy	Reimbursable Out-of-Pocket Expenses
Cost of Revenues	Cost of Revenues
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reported periods. Significant estimates include implicit price concessions, revenue estimates, the allowances for doubtful accounts, deferred tax assets, fair values of acquired assets and assumed liabilities in business combinations, fair value of goodwill and indefinite-lived intangible assets, amortization lives for acquired intangible assets, and accruals for self-insurance reserves, litigation reserves and pensions. Actual results could differ from those estimates. The extent to which the COVID-19 pandemic has and will continue to impact the Company’s business and financial results depend on numerous evolving factors including, but not limited to the magnitude and duration of the COVID-19 pandemic, the impact to worldwide macroeconomic conditions including interest rates, employment rates and health insurance coverage, the speed of the anticipated recovery, and governmental and business reactions to the pandemic. The Company assessed certain accounting matters that generally require consideration of forecasted financial information in context with the information reasonably available to the Company and the unknown future impacts of COVID-19 as of December 31, 2023, and through the date of this Annual Report. The accounting matters assessed included, but were not limited to, the Company’s implicit price concessions and credit losses, equity investments, and the carrying value of goodwill and other long-lived assets. The Company’s future assessment of the magnitude and duration of the COVID-19 pandemic, as well as other factors, could impact the Company’s consolidated financial statements in future reporting periods.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. The Company maintains cash and cash equivalents with various major financial institutions. The total cash and cash equivalent balances that exceeded the balances insured by the Federal Deposit Insurance Commission, were approximately $534.7 and $428.1 at December 31, 2023, and 2022, respectively. Substantially all of the Company’s accounts receivable are with companies in the healthcare or pharmaceutical industry and individuals. However, concentrations of credit risk are mitigated due to the number of the Company’s customers as well as their dispersion across many different geographic regions. Although Dx has receivables due from U.S. and state governmental agencies, the Company does not believe that such receivables represent a credit risk since the related healthcare programs are funded by U.S. and state governments, and payment is primarily dependent upon submitting appropriate documentation. Accounts receivable balances (gross) from Medicare and Medicaid were $86.5 and $85.8 at December 31, 2023, and 2022, respectively. For the Company's operations in Ontario, Canada, the Ontario Ministry of Health and Long-Term Care (Ministry) determines who can establish a licensed community medical laboratory and caps the amount that each of these licensed laboratories can bill the government sponsored healthcare plan. The Ontario government-sponsored healthcare plan covers the cost of commercial laboratory testing performed by the licensed laboratories. The provincial government discounts the annual testing volumes based on certain utilization discounts and establishes an annual maximum it will pay for all community laboratory tests. The agreed-upon reimbursement rates are subject to Ministry review at the end of year and can be adjusted (at the government's discretion) based upon the actual volume and mix of test work performed by the licensed healthcare providers in the province during the year. The capitated accounts receivable balance from the Ontario government sponsored healthcare plan was CAD 5.5 at December 31, 2023. There were no capitated accounts receivables from the Ontario government sponsored healthcare plan at December 31, 2022.
Earnings Per Share	Earnings per Share Basic earnings per share is computed by dividing net earnings attributable to Laboratory Corporation of America Holdings by the weighted average number of common shares outstanding. Diluted earnings per share is computed by dividing net earnings including the impact of dilutive adjustments by the weighted average number of common shares outstanding plus potentially dilutive shares, as if they had been issued at the earlier of the date of issuance or the beginning of the period presented. Potentially dilutive common shares result primarily from the Company’s outstanding stock options, restricted stock awards, performance share awards, and accelerated share repurchases. The following represents a reconciliation of basic earnings per share to diluted earnings per share: 2023 2022 2021 Income Shares Per Share Income Shares Per Share Income Shares Per Share Basic earnings per share $ 418.0 87.1 $ 4.80 $ 1,279.1 91.1 $ 14.05 $ 2,377.3 96.7 $ 24.60 Stock options and stock awards — 0.5 — 0.5 — 0.8 Diluted earnings per share $ 418.0 87.6 $ 4.77 $ 1,279.1 91.6 $ 13.97 $ 2,377.3 97.5 $ 24.39 The following table summarizes the potential common shares not included in the computation of diluted earnings per share because their impact would have been antidilutive: Years Ended December 31, 2023 2022 2021 Stock options 0.2 0.2 0.1
Stock Compensation Plans	Stock Compensation Plans The Company measures stock compensation cost for all equity awards at fair value on the date of grant and recognizes compensation expense over the service period for awards expected to vest. The fair value of restricted stock units is determined based on the number of shares granted and the quoted price of the Company’s Common Stock on the grant date. The grant date fair value of performance awards is based on a Monte Carlo simulated fair value for the relative (as compared to the peer companies) total shareholder return component of the performance awards. Such value is recognized as an expense over the service period, net of estimated forfeitures and the Company's determination of whether it is probable that the performance targets will be achieved. At the end of each reporting period, the Company reassesses the probability of achieving performance targets. The estimation of equity awards that will ultimately vest requires judgment, and the Company considers many factors when estimating expected forfeitures, including types of awards, employee class, and historical experience. Forfeitures are recognized as a reduction of compensation expense in earnings in the period in which they occur. See Note 14 Stock Compensation Plans for assumptions used in calculating compensation expense for the Company’s stock compensation plans.
Cash Equivalents	Cash Equivalents
Inventories	Supplies Inventory
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are recorded at cost. Depreciation and amortization expense is computed on all classes of assets based on their estimated useful lives, as indicated below, using the straight-line method. Years Buildings and building improvements 10 - 55 Machinery and equipment 3 - 10 Furniture and fixtures 5 - 10 Software 3 - 10 Leasehold improvements are amortized over the shorter of their estimated useful lives or the term of the related leases. Expenditures for repairs and maintenance are charged to operations as incurred. Retirements, sales and other disposals of assets are recorded by removing the cost and accumulated depreciation from the related accounts with any resulting gain or loss reflected in the consolidated statements of operations. Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amounts may not be recoverable. If the carrying value is no longer recoverable based upon the undiscounted future cash flows of the asset, the amount of the impairment is the difference between the carrying amount and the fair value of the asset.
Capitalized Software Costs	Capitalized Software Costs The Company capitalizes purchased software that is ready for service and capitalizes software development costs incurred on significant projects starting from the time that the preliminary project stage is completed and the Company commits to funding a project until the project is substantially complete and the software is ready for its intended use. Capitalized costs include direct material and service costs and payroll and payroll-related costs. Research and development (R&D) costs and other computer software maintenance costs related to software development are expensed as incurred. Capitalized software costs are amortized using the straight-line method over the estimated useful life of the underlying system ranging from three to fifteen years, generally five years. Amortization begins once the underlying system is substantially complete and ready for its intended use.
Intangible Assets	Intangible Assets Intangible assets with finite lives are amortized on a straight-line basis over the expected periods to be benefited, as set forth in the table below, such as legal life for patents and technology and contractual lives for non-compete agreements. Years Customer relationships 10 - 36 Patents, licenses and technology 3 - 15 Non-compete agreements 3 - 5 Trade names 1 - 15
Debt Issuance Costs	Debt Issuance Costs The costs related to the issuance of debt are capitalized, netted against the related debt for presentation purposes and amortized to interest expense over the terms of the related debt.
Professional Liability	Professional Liability
Income Taxes	Income Taxes The Company accounts for income taxes utilizing the asset and liability method. Under this method deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and for tax loss carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company does not recognize a tax benefit unless the Company concludes that it is more likely than not that the benefit will be sustained on audit by the taxing authority based solely on the technical merits of the associated tax position. If the recognition threshold is met, the Company recognizes a tax benefit measured at the largest amount of the tax benefit that the Company believes is greater than 50% likely to be realized. The Company records interest and penalties in income tax expense.
Minimum threshold percentage required to recognize income tax benefit (in hundredths)	50%
Derivative Financial Instruments	Derivative Financial Instruments The Company addresses its exposure to market risks, principally the market risk associated with changes in interest rates and currency exchange rates, through a controlled program of risk management that includes, from time to time, the use of derivative financial instruments. The Company does not hold or issue derivative financial instruments for trading purposes. The Company does not believe that its exposure to market risk is material to the Company’s financial position or results of operations. Interest rate swap agreements, which have been used by the Company from time to time in the management of interest rate exposure, are accounted for at fair value. These derivative financial instruments are accounted for as fair value hedges that increase or decrease the value of the Senior Notes with the offset being recorded as a component of other long-term assets or liabilities, as applicable. As the specific terms and notional amounts of the derivative financial instruments match those of the fixed-rate debt being hedged, the derivative instruments are assumed to be perfectly effective hedges and accordingly, there is no impact to the Company's consolidated statements of operations. Cash flows from the interest rate swaps are including in operating activities. Cross currency swap agreements, which have been used by the Company to hedge the foreign currency exposure of its net investment in a foreign subsidiary denominated in non-U.S. currency, are accounted for at fair value. Changes in the fair value of the cross-currency swaps are charged or credited through accumulated other comprehensive income in the Consolidated Balance Sheet until the hedged item is recognized in earnings. The cumulative amount of the fair value hedging adjustments are recognized as currency translation within the Consolidated Statements of Comprehensive Earnings.
Fair Value of Financial Instruments	Fair Value of Financial Instruments Fair value measurements for financial assets and liabilities are determined based on the assumptions that a market participant would use in pricing an asset or liability. A three-tiered fair value hierarchy draws distinctions between market participant assumptions based on (i) observable inputs such as quoted prices in active markets (Level 1), (ii) inputs other than quoted prices in active markets that are observable either directly or indirectly (Level 2), and (iii) unobservable inputs that require the Company to use present value and other valuation techniques in the determination of fair value (Level 3).
Entity Number of Employees	67,000
Research and Development	Research and Development The Company expenses R&D costs as incurred.
Lessee, Leases	Leases All leases with a lease term greater than 12 months, regardless of lease type classification, are recorded as an obligation on the balance sheet with a corresponding right-of-use asset. Both finance and operating leases are reflected as liabilities on the commencement date of the lease based on the present value of the lease payments to be made over the lease term. Right-of-use assets are valued at the initial measurement of the lease liability, plus any initial direct costs or rent prepayments, minus lease incentives and any deferred lease payments. The classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A certain number of these leases contain rent escalation clauses either fixed or adjusted periodically for inflation or market rates that are factored into the Company's determination of lease payments. The Company also has variable lease payments that do not depend on a rate or index, for items such as volume purchase commitments, which are recorded as variable cost when incurred. As most of the Company's leases do not provide an implicit rate, the Company estimates an incremental borrowing rate based on the credit quality of the Company and by comparing interest rates available in the market for similar borrowings, and adjusting this amount based on the impact of collateral over the term of each lease. The Company uses this rate to discount payments to present value. Some operating leases contain renewal options, some of which also include options to early terminate the leases. The exercise of these options is at the Company's discretion and the Company evaluates each renewal option to determine if it is reasonably possible to be exercised and should be included in the accounting lease term. See Note 5 Leases to the Consolidated Financial Statements.
Goodwill and Intangible Assets, Goodwill, Policy	The Company assesses goodwill and indefinite-lived intangibles, which are not amortized, 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 annual impairment test for goodwill includes an option to perform a qualitative assessment of whether it is more likely than not that a reporting unit's fair value is less than its carrying value. Reporting units are businesses with discrete financial information that is available and reviewed by management. If the Company determines that it is more likely than not that the fair value of a reporting unit is less than its carrying value, then the Company performs the quantitative goodwill impairment test. The Company may also choose to bypass the qualitative assessment for any reporting unit in its goodwill assessment and proceed directly to performing the quantitative assessment. The Company recognizes an impairment charge for the amount by which the reporting unit's carrying amount exceeds its fair value. In the qualitative assessment, the Company considers relevant events and circumstances for each reporting unit, including (i) current year results, (ii) financial performance versus management’s annual and five-year strategic plans, (iii) changes in the reporting unit carrying value since prior year, (iv) industry and market conditions in which the reporting unit operates, (v) macroeconomic conditions, including discount rate changes, and (vi) changes in products or services offered by the reporting unit. If applicable, performance in recent years is compared to forecasts included in prior quantitative valuations. Based on the results of the qualitative assessment, if the Company concludes that it is not more likely than not that the fair value of the reporting unit is less than its carrying values of the reporting unit, then no quantitative assessment is performed. The quantitative assessment includes the estimation of the fair value of each reporting unit as compared to the carrying value of the reporting unit. The Company estimates the fair value of a reporting unit using both income-based and market-based valuation methods. The income-based approach is based on the reporting unit's forecasted future cash flows that are discounted to the present value using the reporting unit's weighted average cost of capital. For the market-based approach, the Company utilizes a number of factors such as publicly available information regarding the market capitalization of the Company as well as operating results, business plans, market multiples, and present value techniques. Based upon the range of estimated values developed from the income and market-based methods, the Company determines the estimated fair value for the reporting unit. If the estimated fair value of the reporting unit exceeds the carrying value, the goodwill is not impaired and no further review is required. Management performed its annual goodwill and intangible asset impairment testing as of the beginning of the fourth quarter of 2023. The Company elected to perform the qualitative assessment for goodwill and intangible assets for the domestic Dx reporting unit and the Clinical Trials Testing Solutions (CTTS) reporting unit, and a quantitative assessment for the Early Development (ED) reporting unit, and the Canadian reporting unit which includes indefinite-lived assets consisting of acquired Canadian licenses. Based upon the results of the qualitative and quantitative assessments, the Company concluded that the fair values of its domestic Dx, CTTS and Canadian reporting units, as of October 1, 2023, were greater than the carrying values. However, due to lower demand in the ED reporting unit in late 2023, which the Company anticipates will continue into early 2024 there is an expectation of lower near term revenue and profitability. Therefore, the Company concluded that the fair value of the ED reporting unit was less than carrying value and recorded a goodwill impairment of $333.6 in the BLS segment. Although the Company believes that the current assumptions and estimates used in its goodwill analysis are reasonable, supportable, and appropriate, continued efforts to maintain or improve the performance of these businesses could be impacted by unfavorable or unforeseen changes which could impact the existing assumptions used in the impairment analysis. Various factors could reasonably be expected to unfavorably impact existing assumptions: primarily delays in new customer bookings and the related delay 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. It is possible that the Company's conclusions regarding impairment or recoverability of goodwill or intangible assets in any reporting unit could change in future periods. There can be no assurance that the estimates and assumptions used in the Company's goodwill and intangible asset impairment testing performed as of the beginning of the fourth quarter of 2023 will prove to be accurate predictions of the future, if, for example, (i) the businesses do not perform as projected, (ii) overall economic conditions in 2024 or future years vary from current assumptions (including changes in discount rates), (iii) business conditions or strategies for a specific reporting unit change from current assumptions, including loss of major customers, (iv) investors require higher rates of return on equity investments in the marketplace or (v) enterprise values of comparable publicly traded companies, or actual sales transactions of comparable companies, were to decline, resulting in lower multiples of revenues and EBITDA.
Foreign Currency Transactions and Translations Policy	Foreign Currencies For subsidiaries outside of the U.S. that operate in a local currency environment, income and expense items are translated to U.S. dollars at the monthly average rates of exchange prevailing during the period, assets and liabilities are translated at period-end exchange rates and equity accounts are translated at historical exchange rates. Translation adjustments are accumulated in a separate component of shareholders’ equity in the consolidated balance sheets and are included in the determination of comprehensive income in the consolidated statements of comprehensive earnings and consolidated statements of changes in shareholders’ equity. Transaction gains and losses are included in the determination of net income in the consolidated statements of operations.
Selling, General and Administrative Expenses, Policy	Selling, General and Administrative Expenses Selling, general and administrative expenses consist primarily of administrative payroll and related benefit charges, advertising and promotional expenses, administrative travel and an allocation of facility charges and information technology costs. Cost of advertising is expensed as incurred.

SUMMARY OF SIGNIFICANT ACCOUN_6

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [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: 2023 2022 2021 Income Shares Per Share Income Shares Per Share Income Shares Per Share Basic earnings per share $ 418.0 87.1 $ 4.80 $ 1,279.1 91.1 $ 14.05 $ 2,377.3 96.7 $ 24.60 Stock options and stock awards — 0.5 — 0.5 — 0.8 Diluted earnings per share $ 418.0 87.6 $ 4.77 $ 1,279.1 91.6 $ 13.97 $ 2,377.3 97.5 $ 24.39
Potential common shares not included in computation of diluted earnings per share	Years Ended December 31, 2023 2022 2021 Stock options 0.2 0.2 0.1
Property, Plant and Equipment	Years Buildings and building improvements 10 - 55 Machinery and equipment 3 - 10 Furniture and fixtures 5 - 10 Software 3 - 10
Finite-Lived Intangible Assets	Intangible assets with finite lives are amortized on a straight-line basis over the expected periods to be benefited, as set forth in the table below, such as legal life for patents and technology and contractual lives for non-compete agreements. Years Customer relationships 10 - 36 Patents, licenses and technology 3 - 15 Non-compete agreements 3 - 5 Trade names 1 - 15

REVENUE (Tables)

REVENUE (Tables)	12 Months Ended
	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue [Table Text Block]	The Company's revenue by segment payers/customer groups for the years ended December 31, 2023, 2022 and 2021 is as follows: For the Year Ended For the Year Ended For the Year Ended North America Europe Other Total North America Europe Other Total North America Europe Other Total Payer/Customer Dx Clients 24 % — % — % 24 % 22 % — % — % 22 % 21 % — % — % 21 % Patients 9 % — % — % 9 % 8 % — % — % 8 % 7 % — % — % 7 % Medicare and Medicaid 8 % — % — % 8 % 8 % — % — % 8 % 8 % — % — % 8 % Third party 36 % — % — % 36 % 39 % — % — % 39 % 42 % — % — % 42 % Total Dx revenues by payer 77 % — % — % 77 % 77 % — % — % 77 % 78 % — % — % 78 % BLS Pharmaceutical, biotechnology and medical device companies 10 % 9 % 4 % 23 % 10 % 9 % 4 % 23 % 10 % 9 % 3 % 22 % Total revenues 87 % 9 % 4 % 100 % 87 % 9 % 4 % 100 % 88 % 9 % 3 % 100 %
Contract with Customer, Contract Asset, Contract Liability, and Receivable	December 31, 2023 December 31, 2022 Dx accounts receivable $ 1,135.2 $ 1,046.9 BLS accounts receivable 810.8 769.4 Less BLS allowance for doubtful accounts (32.7) (30.8) Accounts receivable $ 1,913.3 $ 1,785.5 Gross unbilled services $ 192.9 $ 222.3 Less reserve for unbilled services (7.5) (10.6) Unbilled services $ 185.4 $ 211.8 Unearned revenue $ 421.7 $ 310.6

BUSINESS ACQUISITIONS & DISPOSI

BUSINESS ACQUISITIONS & DISPOSITIONS Business Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2023
Business Acquisition [Line Items]
Business Current Year Acquisition ProForma Information Table Text Block	Unaudited Pro Forma Information for 2021 Acquisitions Had the aggregate of the Company's 2021 acquisitions been completed as of January 1, 2021, the Company's pro forma results would have been as follows: Years Ended December 31, 2021 Revenues $ 13,231.8 Earnings from continuing operations 2,198.6

Restructuring and Related Act_2

Restructuring and Related Activities (Tables)	12 Months Ended
	Dec. 31, 2023
Restructuring and Related Activities [Abstract]
Schedule of Restructuring Reserves	The following represents the Company’s restructuring activities for the period indicated: Severance and Other Lease and Other Total Balance as of December 31, 2021 $ 3.7 $ 1.6 $ 5.3 Restructuring charges 24.8 31.1 55.9 Reduction of prior restructuring accruals (1.4) (0.5) (1.9) Cash payments and other adjustments (25.0) (22.8) (47.8) Balance as of December 31, 2022 2.1 9.4 11.5 Restructuring charges 33.4 22.3 55.7 Reduction of prior restructuring accruals (1.7) (4.9) (6.6) Cash payments and other adjustments (26.2) (13.8) (40.0) Balance as of December 31, 2023 $ 7.6 $ 13.0 $ 20.6 Current $ 9.5 Non-current 11.1 $ 20.6

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	Year Ended December 31, 2023 Operating Leases Finance Leases 2024 $ 200.1 $ 11.3 2025 161.2 9.2 2026 114.1 8.6 2027 86.1 8.2 2028 70.7 7.6 Thereafter 330.1 78.3 Total lease payments $ 962.3 $ 123.2 Less imputed interest (147.6) (38.2) Less current portion (165.8) (6.4) Total maturities, due beyond one year $ 648.9 $ 78.6
Lease, Cost [Table Text Block]	December 31, 2023 December 31, 2022 Operating Leases Operating lease ROU assets (included in Property, plant and equipment, net) $ 737.1 $ 738.1 Short-term operating lease liabilities 165.8 163.8 Operating lease liabilities 648.9 652.9 Total operating lease liabilities $ 814.7 $ 816.7 Finance Leases Finance lease ROU assets (included in Other assets) $ 69.5 $ 74.9 Short-term finance lease liabilities 6.4 6.0 Financing lease liabilities 78.6 83.6 Total finance lease liabilities $ 85.0 $ 89.6 Weighted Average Remaining Lease Term Operating leases 8.4 9.0 Finance leases 14.7 15.6 Weighted Average Discount Rate Operating leases 4.1 % 3.6 % Finance leases 5.3 % 5.5 %
Cash Flow, Supplemental Disclosures [Text Block]	SUPPLEMENTAL CASH FLOW INFORMATION Years Ended December 31, 2023 2022 2021 Supplemental schedule of cash flow information: Cash paid during period for: Interest $ 221.5 $ 196.7 $ 194.5 Income taxes, net of refunds 206.8 474.9 964.7 Disclosure of non-cash financing and investing activities: Change in accrued property, plant and equipment 13.2 (5.6) 11.3
Supplemental Cash Flow Information	Years Ended December 31, 2023 2022 2021 Supplemental schedule of cash flow information: Cash paid during period for: Interest $ 221.5 $ 196.7 $ 194.5 Income taxes, net of refunds 206.8 474.9 964.7 Disclosure of non-cash financing and investing activities: Change in accrued property, plant and equipment 13.2 (5.6) 11.3
Lease Disclosure Table Text Block	For the Year Ended December 31, 2023 December 31, 2022 Operating lease cost $ 202.6 $ 198.1 Finance lease cost: Amortization of right-of-use assets $ 7.1 $ 8.0 Interest on lease liabilities 4.8 5.2 Total finance lease cost $ 11.9 $ 13.2 Supplemental cash flow information related to leases was as follows: For the Year Ended December 31, 2023 December 31, 2022 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ (209.7) $ (200.2) Operating cash flows from finance leases (4.8) (5.2) Financing cash flows from finance leases (12.6) (12.3) ROU assets obtained in exchange for lease obligations: Operating leases $ 106.4 $ 159.2 Finance leases 2.3 —

PROPERTY, PLANT AND EQUIPMENT_2

PROPERTY, PLANT AND EQUIPMENT, NET (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property, plant and equipment, net	December 31, 2023 December 31, 2022 Land $ 98.8 $ 98.5 Buildings and building improvements 1,083.8 1,009.8 Machinery and equipment 2,008.0 1,820.4 Software 924.7 811.6 Leasehold improvements 515.8 484.0 Furniture and fixtures 106.5 109.6 Construction in progress 342.2 306.5 Operating lease ROU assets 737.1 738.1 5,816.9 5,378.5 Less accumulated depreciation (2,905.1) (2,584.4) $ 2,911.8 $ 2,794.1

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS (Tables)	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in Carrying Amount of Goodwill	The changes in the carrying amount of goodwill (net of impairment) for the years ended December 31, 2023 and 2022 were as follows: Dx BLS Total December 31, 2023 December 31, 2022 December 31, 2023 December 31, 2022 December 31, 2023 December 31, 2022 Balance as of January 1 $ 4,533.5 $ 4,046.2 $ 1,590.2 $ 1,844.8 $ 6,123.7 $ 5,891.0 Goodwill acquired during the year 296.9 557.9 — 40.6 296.9 598.5 Impairment — — (333.6) (260.0) (333.6) (260.0) Foreign currency impact and other adjustments to goodwill (16.5) (70.6) 72.0 (35.2) 55.5 (105.8) Balance at end of year $ 4,813.9 $ 4,533.5 $ 1,328.6 $ 1,590.2 $ 6,142.5 $ 6,123.7
Components of identifiable intangible assets	The components of identifiable intangible assets are as follows: December 31, 2023 December 31, 2022 Gross Accumulated Net Gross Accumulated Net Customer relationships $ 3,868.6 $ (1,367.2) $ 2,501.4 $ 3,490.0 $ (1,169.7) $ 2,320.3 Patents, licenses and technology 526.6 (273.3) 253.3 520.4 (243.3) 277.1 Non-compete agreements 130.3 (60.4) 69.9 80.1 (46.8) 33.3 Trade names 16.4 (6.1) 10.3 16.4 (3.5) 12.9 Land use rights 3.5 (2.7) 0.8 3.5 (2.2) 1.3 Canadian licenses 498.8 — 498.8 468.7 — 468.7 Content 5.1 (4.7) 0.4 5.1 (4.2) 0.9 In process research and development 9.1 (2.0) 7.1 9.1 — 9.1 $ 5,058.4 $ (1,716.4) $ 3,342.0 $ 4,593.3 $ (1,469.7) $ 3,123.6
Acquired amortizable intangible assets and their respective weighted average amortization periods	A summary of amortizable intangible assets acquired during 2023, and their respective weighted average amortization periods are as follows: Amount Weighted Average Customer relationships $ 260.6 12.5 Non-compete agreements 53.3 0.8 $ 313.9 13.3

ACCRUED EXPENSES AND OTHER (Tab

ACCRUED EXPENSES AND OTHER (Tables)	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Accrued expenses and other	December 31, 2023 December 31, 2022 Employee compensation and benefits $ 431.4 $ 444.6 Accrued taxes payable 127.5 105.6 Other 245.1 236.8 $ 804.0 $ 787.0

DEBT (Tables)

DEBT (Tables)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Debt Disclosure [Abstract]
Schedule of Maturities of Long-term Debt [Table Text Block]		The scheduled payments of long-term debt at the end of 2023 are summarized as follows: 2024 $ 1,001.1 2025 1,000.0 2026 500.0 2027 600.0 2028 — Thereafter 1,981.0 Total scheduled payments 5,082.1 Less current portion (1,001.1) Long-term debt, due beyond one year $ 4,081.0
Short-term borrowings and current portion of long-term debt		Short-term borrowings and current portion of long-term debt at December 31, 2023, and 2022 consisted of the following: December 31, 2023 December 31, 2022 4.00% senior notes due 2023 — 300.0 2.30% senior notes due 2024 400.0 — 3.25% senior note due 2024 600.0 — Debt issuance costs (1.3) (0.4) Current portion of note payable 1.1 1.7 Total short-term borrowings and current portion of long-term debt $ 999.8 $ 301.3
Long-term debt	Long-term debt at December 31, 2023, and 2022 consisted of the following: December 31, 2023 December 31, 2022 2.30% senior notes due 2024 — 400.0 3.25% senior notes due 2024 — 600.0 3.60% senior notes due 2025 1,000.0 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 2.70% senior notes due 2031 430.4 420.3 4.70% senior notes due 2045 900.0 900.0 Debt issuance costs (26.3) (33.8) Note payable 0.6 2.3 Total long-term debt $ 4,054.7 $ 5,038.8
Schedule of Long-term Debt Instruments	Long-term debt at December 31, 2023, and 2022 consisted of the following: December 31, 2023 December 31, 2022 2.30% senior notes due 2024 — 400.0 3.25% senior notes due 2024 — 600.0 3.60% senior notes due 2025 1,000.0 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 2.70% senior notes due 2031 430.4 420.3 4.70% senior notes due 2045 900.0 900.0 Debt issuance costs (26.3) (33.8) Note payable 0.6 2.3 Total long-term debt $ 4,054.7 $ 5,038.8

PREFERRED STOCK AND COMMON SH_2

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY (Tables)	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
Common shares issued and outstanding [Text Block]	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 December 31, 2023 and 2022.
Changes in common shares issued and held in treasury [Text Block]	The changes in common shares issued and held in treasury are summarized below: Common Shares Issued 2023 2022 2021 Common stock issued at January 1 88.2 93.1 97.5 Common stock issued under employee stock plans 0.5 0.7 0.8 Purchase of common stock (4.8) (5.6) (5.2) Common stock issued at December 31 83.9 88.2 93.1
Accumulated Other Comprehensive Earnings Components [Text Block]	The components of accumulated other comprehensive earnings are as follows: Foreign Net Accumulated Balance at December 31, 2021 $ (125.9) $ (66.0) $ (191.9) Current year adjustments (335.5) 52.5 (283.0) Pension settlement charge — (3.1) (3.1) Amounts reclassified from accumulated other comprehensive earnings (a) (0.9) (4.6) (5.5) Tax effect of adjustments — (9.7) (9.7) Balance at December 31, 2022 $ (462.3) $ (30.9) $ (493.2) Fortrea Holdings Inc. spin 231.6 6.4 238.0 Current year adjustments 183.1 30.1 213.2 Pension settlement charge — (10.9) (10.9) Amounts reclassified from accumulated other comprehensive earnings (a) — (4.6) (4.6) Tax effect of adjustments — (1.8) (1.8) Balance at December 31, 2023 $ (47.6) $ (11.7) $ (59.3)

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Valuation Allowance [Line Items]
Summary of Valuation Allowance [Table Text Block]	The table below provides a rollforward of the valuation allowance: December 31, 2023 December 31, 2022 December 31, 2021 Beginning balance $ 151.3 $ 149.2 $ 167.6 Movements charged to expense (8.9) 10.2 6.8 Reductions and other adjustments 7.8 (8.1) (25.2) Ending balance $ 150.2 $ 151.3 $ 149.2
Schedule of Income before Income Tax, Domestic and Foreign	The sources of income before taxes, classified between domestic and foreign entities, are as follows: 2023 2022 2021 Domestic $ 504.0 $ 1,097.9 $ 2,455.0 Foreign 64.9 139.5 432.6 Total pre-tax income $ 568.9 $ 1,237.4 $ 2,887.6
Provision for Income Tax Expense (Benefit)	The components of income tax expense attributable to continuing operations are as follows: Years Ended December 31, 2023 2022 2021 Current tax expense: Federal $ 183.1 $ 150.8 $ 500.0 State 38.9 25.4 156.5 Foreign 44.6 34.0 71.9 $ 266.6 $ 210.2 $ 728.4 Deferred tax expense/(benefit): Federal $ (63.1) $ 15.8 $ (36.7) State (31.6) 0.6 (9.0) Foreign 16.6 7.3 7.3 (78.1) 23.7 (38.4) Total income tax expense $ 188.5 $ 233.9 $ 690.0
Schedule of Effective Income Tax Rate Reconciliation	The effective tax rates on earnings before income taxes are reconciled to statutory U.S. income tax rates as follows: Years Ended December 31, 2023 2022 2021 Statutory U.S. rate 21.0 % 21.0 % 21.0 % State and local income taxes, net of U.S. federal income tax effect 4.0 4.2 3.9 Foreign earnings taxed at lower rates than the statutory U.S. rate (2.2) (0.7) (0.7) Tax credits (3.8) (5.4) (0.1) Impairment of assets 10.8 3.7 — Limitation of officer compensation 1.7 1.2 0.3 Worthless stock loss (2.6) — — Deferred tax adjustments 2.7 (2.4) (0.1) Other 1.5 (2.7) (0.4) Effective rate 33.1 % 18.9 % 23.9 %
Schedule of Deferred Tax Assets and Liabilities	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are as follows: December 31, 2023 December 31, 2022 Deferred tax assets: Accounts receivable $ 27.9 $ 19.4 Employee compensation and benefits 81.7 96.5 Operating lease liability 191.4 182.6 Acquisition and restructuring reserves 9.2 7.0 Capitalized R&D costs 142.9 44.1 Tax loss carryforwards 246.9 241.9 Other 95.1 95.1 Total gross deferred tax assets 795.1 686.6 Less: valuation allowance (150.2) (151.3) Deferred tax assets, net of valuation allowance $ 644.9 $ 535.3 Deferred tax liabilities: Right of use asset $ (175.3) $ (170.2) Intangible assets (614.8) (605.1) Property, plant and equipment (163.5) (166.5) Other (66.2) (62.7) Total gross deferred tax liabilities $ (1,019.8) $ (1,004.5) Net deferred tax liabilities $ (374.9) $ (469.2)
Reconciliation of Unrecognized Tax Benefits from Uncertain Tax Positions		The following table shows a reconciliation of the unrecognized income tax benefits, excluding interest and penalties, from uncertain tax positions for the years ended December 31, 2023, 2022 and 2021: 2023 2022 2021 Balance as of January 1 $ 37.5 $ 39.6 $ 18.6 Increase in reserve for tax positions taken in the current year 1.8 1.8 — Increase in reserve for tax positions taken in a prior period 10.4 10.6 31.1 Decrease in reserve for tax positions taken in a prior period (4.0) — (8.1) Decrease in reserve as a result of settlements (7.2) (10.4) — Decrease in reserve as a result of lapses in the statute of limitations (8.6) (4.1) (2.0) Balance as of December 31 $ 29.9 $ 37.5 $ 39.6

STOCK COMPENSATION PLANS (Table

STOCK COMPENSATION PLANS (Tables)	12 Months Ended
	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Disclosure of Share Based Compensation Arrangements by Share Based Payment Awards	hanges in options outstanding under the plans for the period indicated were as follows: Number of Weighted-Average Weighted-Average Aggregate Outstanding at December 31, 2022 0.5 169.31 Granted 0.1 219.83 Outstanding at December 31, 2023 0.6 174.45 6.0 $ 32.2 Exercisable at December 31, 2023 0.5 159.05 5.4 $ 31.3
Disclosure of the Impact of Stock Options Exercised	Cash received by the Company from option exercises, the actual tax benefit realized for the tax deductions and the aggregate intrinsic value of options exercised from option exercises under all share-based payment arrangements during the years ended December 31, 2023, 2022, and 2021 were as follows: 2023 2022 2021 Cash received by the Company $ 2.9 $ 7.1 $ 6.8 Tax benefits realized $ 0.7 $ 1.8 $ 1.7 Aggregate intrinsic value $ 0.7 $ 8.2 $ 13.4
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	The following table shows the weighted average grant-date fair values of options issued during the respective year and the weighted average assumptions that the Company used to develop the fair value estimates: 2023 2022 2021 Fair value per option $ 72.27 $ 68.35 $ 55.75 Weighted average expected life (in years) 6.0 6.0 6.0 Risk free interest rate 3.4 % 2.0 % 0.6 % Expected volatility 29.8 % 28.6 % 28.6 % Expected dividend yield 1.4 % 0.9 % N/A The Company uses the Black-Scholes model to calculate the fair value of the employee’s purchase right. The fair value of the employee’s purchase right and the assumptions used in its calculation are as follows: 2023 2022 2021 Fair value of the employee’s purchase right $ 49.19 $ 62.50 $ 59.89 Valuation assumptions Risk free interest rate 5.0% 1.3% 0.1% Expected volatility 0.3 0.3 0.3 Expected dividend yield 1.4% 0.9% —%
Schedule of Nonvested Share Activity	The following table shows a summary of non-vested shares for the year ended December 31, 2023: Number of Weighted-Average Non-vested at January 1, 2023 1.1 $ 231.30 Granted 0.5 224.11 Vested (0.5) 208.71 Canceled (0.1) 235.27 Non-vested at December 31, 2023 1.0 $ 248.41

PENSION AND POSTRETIREMENT PL_2

PENSION AND POSTRETIREMENT PLANS Pension and Postretirement Plans (Tables)	12 Months Ended
	Dec. 31, 2023
Defined Benefit Plan, Plan Amendment [Abstract]
Schedule of Defined Benefit Plans Disclosures [Table Text Block]	U. S. Plans Non-U.S. Plans Year ended December 31, 2023 2022 2021 2023 2022 2021 Service cost for benefits earned $ 3.9 $ 2.8 $ 3.9 1.4 2.4 2.2 Interest cost on benefit obligation 12.3 9.1 8.3 15.2 9.1 7.2 Expected return on plan assets (11.6) (12.9) (17.3) (16.7) (15.8) (14.3) Net amortization and deferral 4.5 4.6 10.0 0.1 0.8 1.9 Settlements 10.9 4.1 3.7 — (1.1) — Defined-benefit plan costs $ 20.0 $ 7.7 $ 8.6 — (4.6) (3.0) Service costs are the only component of net periodic benefit costs recorded within Operating income. For the year ended December 31, 2023, the Company recognized a partial plan settlement charge of $10.9 as a component of Other, net. The amounts recognized in accumulated other comprehensive earnings are as follows: U. S. Plans Non-U.S. Plans Year ended December 31, 2023 2022 2023 2022 Net actuarial loss in accumulated other comprehensive earnings $ 47.2 $ 60.9 $ 19.1 $ 22.6 U.S. Plans Non-U.S. Plans Year Ended December 31, 2023 2022 2023 2022 Balance at beginning of the year $ 259.5 $ 333.3 $ 319.9 $ 569.8 Service cost 3.9 2.8 1.4 2.4 Interest cost 12.3 9.1 15.2 9.1 Actuarial (gain) loss 11.7 (58.4) 7.0 (187.7) Benefits and administrative expenses paid (55.5) (27.3) (14.2) (19.5) Foreign currency exchange rate changes — — 16.4 (54.2) Balance at end of the year $ 231.9 $ 259.5 $ 345.7 $ 319.9 The estimated benefit payments, which were used in the calculation of projected benefit obligations, are expected to be paid as follows: U. S. Plans Non-U. S. Plans 2024 $ 21.8 $ 16.4 2025 22.4 16.2 2026 21.6 17.6 2027 20.8 18.0 2028 21.1 18.3 Years 2029 to 2033 92.2 97.8 Year ended December 31, 2023 2022 2021 Interest cost on benefit obligation $ 0.2 $ 0.1 $ 0.1 Net amortization and deferral — 0.2 0.3 Post-retirement medical plan costs $ 0.2 $ 0.3 $ 0.4 A summary of the changes in the accumulated post-retirement benefit obligation follows: 2023 2022 Balance at January 1 $ 3.9 $ 5.2 Interest cost on benefit obligation 0.2 0.1 Actuarial loss (0.2) (0.9) Benefits paid (0.3) (0.5) Balance at December 31 $ 3.6 $ 3.9 Recorded as: Accrued expenses and other $ 0.6 $ 0.6 Other liabilities 3.0 3.3 $ 3.6 $ 3.9
Schedule of Changes in Fair Value of Plan Assets [Table Text Block]	U.S. Plans Non-U.S. Plans Year Ended December 31, 2023 2022 2023 2022 Balances at beginning of the year $ 226.8 $ 299.9 $ 301.2 $ 485.2 Company contributions — — 14.1 13.8 Actual return on plan assets 21.6 (48.2) 18.0 (134.7) Benefits and administrative expenses paid (53.1) (24.9) (13.7) (14.9) Foreign currency exchange rate changes — — 16.3 (48.2) Fair value of plan assets at end of year $ 195.3 $ 226.8 $ 335.9 $ 301.2
Schedule of Net Funded Status [Table Text Block]	U.S. Plans Non-U.S. Plans Year Ended December 31, 2023 2022 2023 2022 Funded status $ 36.6 $ 32.7 $ 9.8 $ 22.8 Recorded as: Other assets $ — $ 2.2 $ 21.5 $ 7.0 Accrued expenses and other 2.5 2.4 0.7 0.6 Other liabilities 34.1 32.5 30.6 29.2
Defined Benefit Plan, Assumptions [Table Text Block]	Weighted average assumptions used to determine net periodic benefit costs are as follows: U. S. Plans Non-U.S. Plans Year ended December 31, 2023 2022 2021 2023 2022 2021 Discount rate 5.5 % 2.8 % 2.4 % 4.0 % 2.1 % 1.1 % Salary increases N/A N/A N/A 2.0 % 2.0 % 2.0 % Expected long term rate of return 6.0 % 4.5 % 6.0 % 5.3 % 3.6 % 3.1 % Cash balance interest credit rate 4.0 % 4.0 % 4.0 % N/A N/A N/A Weighted average assumptions used to determine net periodic benefit obligations are as follows: U. S. Plans Non-U.S. Plans Year ended December 31, 2023 2022 2023 2022 Discount rate 5.1 % 5.5 % 4.3 % 4.8 % Salary increases N/A N/A 2.0 % 2.0 % The weighted average asset allocation of the plan assets as of December 31, 2023, by asset category is as follows: December 31, 2023 U.S. Plans Non-U.S. Plans Equity securities 19.8 % 26.6 % Debt securities 76.4 % 40.8 % Annuities — % 15.7 % Real estate 2.1 % 3.3 % Other 1.7 % 13.7 % The weighted average target asset allocation of the plan assets is as follows: U.S. Plans Non U.S. Plans Equity securities 13.0% to 25.5 % 25.0% to 35.0% Debt securities 67.0% to 87.0 % 35.0% to 45.0% Annuities — % to — % 10.0% to 20.0% Real estate 0.5 % to 4.3 % —% to 10.0% Other — % to 5.0 % 10.0% to 25.0%
Defined Benefit Plan Fair Value Of Plan Assets By Category [Table Text Block]	The fair values of the assets at December 31, 2023, and 2022, by asset category are as follows: Asset Category Level of Valuation Input Fair Value Investments valued using NAV per share Total U.S Plans Cash and cash equivalents Level 1 $ 3.3 $ — $ 3.3 U.S. equity index funds — 27.3 27.3 International equity index funds — 11.4 11.4 Real estate — 4.0 4.0 General bond index funds — 149.3 149.3 Total fair value $ 3.3 $ 192.0 $ 195.3 Non U.S. Plans Cash and cash equivalents Level 1 $ 46.2 $ — $ 46.2 Annuities Level 3 52.8 — 52.8 Pooled investment funds — 236.9 236.9 Total fair value $ 99.0 $ 236.9 $ 335.9 Asset Category Level of Valuation Input Fair Value Investments valued using NAV per share Total U.S Plans Cash and cash equivalents Level 1 $ 3.9 $ — $ 3.9 U.S. equity index funds — 39.6 39.6 International equity index funds — 17.0 17.0 Real estate index fund — 5.0 5.0 General bond index funds — 161.3 161.3 Total fair value $ 3.9 $ 222.9 $ 226.8 Non U.S. Plans Cash and cash equivalents Level 1 $ 3.0 $ — $ 3.0 Annuities Level 3 50.1 — 50.1 Pooled investment funds — 248.1 248.1 Total fair value $ 53.1 $ 248.1 $ 301.2 The fair market value of index funds and pooled investment funds are valued using the net asset value (NAV) unit price provided by the fund administrator. The NAV is based on the value of the underlying assets owned by the fund. The fair value of annuity investments are based on discounted cash flow techniques using unobservable valuation inputs such as discount rates and actuarial mortality tables. Fair Value Measurement of Level 3 Pension Assets Annuities Balance at January 1, 2022 $ 81.3 Actual return on plan assets (31.2) Balance at December 31, 2022 50.1 Actual return on plan assets 2.7 Balance at December 31, 2023 $ 52.8
Assumed Benefit Payments By Year [Table Text Block]	The following assumed benefit payments under the Company's post-retirement benefit plan, which reflect expected future service, as appropriate, and which were used in the calculation of projected benefit obligations, are expected to be paid as follows: 2024 $ 0.6 2025 0.5 2026 0.4 2027 0.3 2028 0.3 Years 2029 and thereafter 1.0

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Population of Financial Assets and Liabilities Subject to Fair Value Measurements	The Company’s population of financial assets and liabilities subject to fair value measurements as of December 31, 2023, and 2022 were as follows: Fair Value Measurements as of December 31, 2023 Balance Sheet Classification Fair Value as of December 31, 2023 Using Fair Value Hierarchy 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 Measurements as of December 31, 2022 Balance Sheet Classification Fair Value as of December 31, 2022 Using Fair Value Hierarchy Level 1 Level 2 Level 3 Noncontrolling interest put Noncontrolling interest $ 15.0 $ — $ 15.0 $ — Cross currency swaps Other liabilities, net 45.7 — 45.7 — Interest rate swaps Other liabilities 79.7 — 79.7 — Cash surrender value of life insurance policies Other assets, net 100.7 — 100.7 — Deferred compensation liability Other liabilities 96.9 — 96.9 — Contingent consideration Accrued expenses and other/Other liabilities 77.4 — — 77.4

DERIVATIVE INSTRUMENTS AND HE_2

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Tables)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2021
Derivative [Line Items]
Schedule of Derivative Liabilities at Fair Value [Table Text Block]	The table below presents the fair value of derivatives on a gross basis and the balance sheet classification of those instruments: December 31, 2023 December 31, 2022 Fair Value of Derivative Fair Value of Derivative Balance Sheet Caption Asset Liability U.S. Dollar Notional Asset Liability U.S. Dollar Notional Interest rate swap Other liabilities — 69.6 500.0 — 79.7 500.0 Cross currency swaps Accrued expenses and other/Other liabilities — 109.0 600.0 — 45.7 600.0
Derivative Instruments, Gain (Loss) [Table Text Block]		The table below provides information regarding the location and amount of pretax (gains) losses of derivatives designated in fair value hedging relationships: Amount included in other comprehensive income Amounts reclassified to the Year Ended December 31, Year Ended December 31, 2023 2022 2021 2023 2022 2021 Cross currency swaps $ (63.3) $ (12.9) $ 7.6 $ — $ 0.9 $ —

SUPPLEMENTAL CASH FLOW INFORM_2

SUPPLEMENTAL CASH FLOW INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2023
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	Years Ended December 31, 2023 2022 2021 Supplemental schedule of cash flow information: Cash paid during period for: Interest $ 221.5 $ 196.7 $ 194.5 Income taxes, net of refunds 206.8 474.9 964.7 Disclosure of non-cash financing and investing activities: Change in accrued property, plant and equipment 13.2 (5.6) 11.3

BUSINESS SEGMENT INFORMATION (T

BUSINESS SEGMENT INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment [Table Text Block]	2023 2022 2021 Revenues: Dx $ 9,415.1 $ 9,203.5 $ 10,363.6 BLS 2,774.2 2,697.3 2,860.7 Intercompany eliminations and other (27.7) (36.9) (88.2) Total revenues $ 12,161.6 $ 11,863.9 $ 13,136.1 Operating Earnings: Dx segment operating income $ 1,591.3 $ 2,025.5 $ 3,205.6 BLS segment operating income 396.3 389.1 501.0 Segment operating income 1,987.6 2,414.6 3,706.6 General corporate and unallocated expenses (644.1) (468.8) (404.5) Amortization of intangibles and other assets (219.8) (193.6) (229.5) Restructuring and other charges (49.1) (54.0) (24.0) Goodwill and other asset impairments (349.0) (261.7) — Total operating income $ 725.6 $ 1,436.5 $ 3,048.6 2023 2022 2021 Depreciation Dx $ 236.1 $ 227.1 $ 238.6 BLS 112.5 112.8 106.3 General corporate 8.9 3.7 2.6 Total depreciation $ 357.5 $ 343.6 $ 347.5 Geographic Distribution of property, plant and equipment, net: December 31, 2023 Dx BLS Total North America $ 1,799.2 $ 619.0 $ 2,418.2 Europe — 394.7 394.7 Other — 98.9 98.9 Total property, plant and equipment, net $ 1,799.2 $ 1,112.6 $ 2,911.8 December 31, 2022 Dx BLS Total North America $ 1,669.2 $ 639.7 $ 2,308.9 Europe — 382.4 382.4 Other — 102.7 102.7 Total property, plant and equipment, net $ 1,669.2 $ 1,124.9 $ 2,794.1

SUMMARY OF SIGNIFICANT ACCOUN_7

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Goodwill, Impairment Loss	$ 333,600,000	$ 260,000,000
Inventory Valuation Reserves	66,100,000	23,300,000
Accounts receivable balances (gross) from Medicare and Medicaid	$ 86,500,000	85,800,000
Ownership percentage below which investments are generally accounted for on the cost method (in hundredths)	20%
Cash, Uninsured Amount	$ 534,700,000	$ 428,100,000
Minimum threshold percentage required to recognize income tax benefit (in hundredths)	50%
Percent of gross accounts receivable due from patients	20.40%	15.30%
Inventory, Finished Goods, Gross	$ 89,500,000	$ 57,800,000
Other Inventory, Supplies, Gross	385,100,000	412,800,000
Goodwill and Intangible Asset Impairment	349,000,000	261,700,000	$ 0
Goodwill	$ 6,142,500,000	$ 6,123,700,000	$ 5,891,000,000
Earnings Per Share	Earnings per Share Basic earnings per share is computed by dividing net earnings attributable to Laboratory Corporation of America Holdings by the weighted average number of common shares outstanding. Diluted earnings per share is computed by dividing net earnings including the impact of dilutive adjustments by the weighted average number of common shares outstanding plus potentially dilutive shares, as if they had been issued at the earlier of the date of issuance or the beginning of the period presented. Potentially dilutive common shares result primarily from the Company’s outstanding stock options, restricted stock awards, performance share awards, and accelerated share repurchases. The following represents a reconciliation of basic earnings per share to diluted earnings per share: 2023 2022 2021 Income Shares Per Share Income Shares Per Share Income Shares Per Share Basic earnings per share $ 418.0 87.1 $ 4.80 $ 1,279.1 91.1 $ 14.05 $ 2,377.3 96.7 $ 24.60 Stock options and stock awards — 0.5 — 0.5 — 0.8 Diluted earnings per share $ 418.0 87.6 $ 4.77 $ 1,279.1 91.6 $ 13.97 $ 2,377.3 97.5 $ 24.39 The following table summarizes the potential common shares not included in the computation of diluted earnings per share because their impact would have been antidilutive: Years Ended December 31, 2023 2022 2021 Stock options 0.2 0.2 0.1
Stock Options (in shares)	0.2	0.2	0.1
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase (Decrease) in Deferred Liabilities	$ 78,100,000	$ (26,300,000)	$ 37,300,000
Accounts receivable from Ontario government sponsored healthcare plan	$ 5,500,000

Discontinued Operations and Dis

Discontinued Operations and Disposal Groups (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Senior Notes	$ 570
Disposal Group, Including Discontinued Operation, Fortrea Senior Notes Interest Rate	7.50%
Disposal Group, Including Discontinued Operation, Fortrea Distribution	$ 1,600
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	1,520
Disposal Group, Including Discontinued Operation, Revenue	1,506.6	$ 3,012.9	$ 2,984.8
Disposal Group, Including Discontinued Operation, Costs of Goods Sold	1,244.5	2,336.7	2,352.9
Disposal Group, Including Discontinued Operation, Gross Profit (Loss)	262.1	676.2	631.9
Disposal Group, Including Discontinued Operation, General and Administrative Expense	184.1	233.5	261.8
Disposal Group, Including Discontinued Operation, Depreciation and Amortization	31.9	65.7	140.1
Disposal group, including discontinued operations, goodwill and other asset impairment	0	9.8	0
Disposal Group, Including Discontinued Operation, Restructuring and other charges	3	29.8	19.1
Disposal Group, Including Discontinued Operation, Operating Income (Loss)	43.1	337.4	210.9
Disposal Group, Including Discontinued Operation, Interest Expense	(0.5)	(0.5)	(0.3)
Disposal Group, Including Discontinued Operation, Investment income (expense)	(1.2)
Disposal Group, Including Discontinued Operation, Interest Income		1.4	1.4
Disposal Group, Including Discontinued Operations, Other Nonoperating income (expense)	4.2	6.9	27
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	45.6	345.2	239
Discontinued Operation, Tax Effect of Discontinued Operation	6.8	68.1	57.1
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	38.8	$ 277.1	$ 181.9
Fortrea Revolver due 2028
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	450
Fortrea Term Loan A maturing 2028
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	500
Fortrea Term Loan B maturing 2028
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	$ 570

REVENUE (Details)

REVENUE (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	100%	100%	100%
Revenues	$ 12,161,600,000	$ 11,863,900,000	$ 13,136,100,000
Percent of Domestic Revenue	83.70%	83.70%	83.60%
Contract with Customer, Asset, before Allowance for Credit Loss	$ 192,900,000	$ 222,300,000
Allowance for Credit Loss, Receivable, Other, Current	(7,500,000)	(10,600,000)
Contract with Customer, Asset, after Allowance for Credit Loss, Current	185,400,000	211,800,000
Contract with Customer, Liability	421,700,000	310,600,000
Deferred Revenue, Revenue Recognized	78,900,000	99,700,000	$ 110,700,000
Accounts Receivable, Allowance for Credit Loss	32,700,000	30,800,000	9,800,000
Unbilled Services, Allowance for Credit Loss	7,500,000	10,500,000	13,900,000
Note Receivable, Allowance for Credit Loss	700,000	700,000	700,000
Allowance for Credit Loss	40,900,000	42,000,000	24,400,000
Accounts Receivable, Credit Loss Expense (Reversal)	6,300,000	11,700,000
Unbilled Services, Credit Loss Expense (Reversal)	0	0
Note Receivable, Credit Loss Expense (Reversal)	0	0
Credit Loss Expense (Reversal)	6,300,000	11,700,000
Allowance for Credit Loss, Write Off	$ (7,400,000)	(5,900,000)
Sales Commission Amortization Period Maximum	5 years
Sales Commission Amortization Period Minimum	1 year
Geographic Distribution, Domestic [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 10,177,700,000	$ 9,930,300,000	$ 10,981,200,000
Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	8%	8%	8%
Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	9%	9%	9%
North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	87%	87%	88%
Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	4%	4%	3%
Covance Drug Development [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed		23%
Covance Drug Development [Member] | Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	23%	23%	22%
Covance Drug Development [Member] | Europe [Member] | Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	9%	9%	9%
Covance Drug Development [Member] | North America | Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	10%	10%	10%
Covance Drug Development [Member] | Other countries [Member] | Biopharmaceutical and medical device companies [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	4%	4%	3%
LabCorp Diagnostics [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	77%	77%	78%
LabCorp Diagnostics [Member] | Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	36%	39%	42%
LabCorp Diagnostics [Member] | Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	9%	8%	7%
LabCorp Diagnostics [Member] | Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	24%	22%	21%
LabCorp Diagnostics [Member] | Europe [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0%	0%	0%
LabCorp Diagnostics [Member] | Europe [Member] | Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0%	0%	0%
LabCorp Diagnostics [Member] | Europe [Member] | Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0%	0%	0%
LabCorp Diagnostics [Member] | Europe [Member] | Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0%	0%	0%
LabCorp Diagnostics [Member] | Europe [Member] | Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0%	0%	0%
LabCorp Diagnostics [Member] | North America
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	77%	77%	78%
LabCorp Diagnostics [Member] | North America | Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	36%	39%	42%
LabCorp Diagnostics [Member] | North America | Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	8%	8%	8%
LabCorp Diagnostics [Member] | North America | Self-Pay [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	9%	8%	7%
LabCorp Diagnostics [Member] | North America | Client [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	24%	22%	21%
LabCorp Diagnostics [Member] | Other countries [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0%	0%	0%
LabCorp Diagnostics [Member] | Other countries [Member] | Third party [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0%	0%	0%
LabCorp Diagnostics [Member] | Other countries [Member] | Medicare and Medicaid [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue Contributed	0%	0%	0%
Maximum [Member]
Capitalized Contract Cost, Amortization Period	5 years
Capitalized Contract Cost, Amortization Period	5 years
Minimum [Member]
Capitalized Contract Cost, Amortization Period	2 years
Capitalized Contract Cost, Amortization Period	2 years
Accounts Receivable [Member]
Allowance for Credit Loss, Write Off	$ (4,400,000)	$ (9,300,000)
Unbilled Contracts Receivable
Allowance for Credit Loss, Write Off	3,000,000	(3,400,000)
Notes Receivable
Allowance for Credit Loss, Write Off	$ 0	$ 0

Receivables, Loans, Notes Recei

Receivables, Loans, Notes Receivable, and Others (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Receivables [Abstract]
Accounts Receivable, Allowance for Credit Loss	Accounts Receivable Unbilled Services Note and Other Receivables Total Allowance for credit losses as of December 31, 2021 $ 9.8 $ 13.9 $ 0.7 $ 24.4 Credit loss expense 11.7 — — 11.7 Write offs 9.3 (3.4) — 5.9 Allowance for credit losses as of December 31, 2022 $ 30.8 $ 10.5 $ 0.7 $ 42.0 Credit loss expense 6.3 — — 6.3 Write offs (4.4) (3.0) — (7.4) Ending allowance for credit losses as of December 31, 2023 $ 32.7 $ 7.5 $ 0.7 $ 40.9
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable, Allowance for Credit Loss	$ (32.7)	$ (30.8)	$ (9.8)
Contract with Customer, Asset, before Allowance for Credit Loss	192.9	222.3
Allowance for Credit Loss, Receivable, Other, Current	(7.5)	(10.6)
Contract with Customer, Liability	421.7	310.6
LabCorp Diagnostics [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable, before Allowance for Credit Loss	1,135.2	1,046.9
Covance Drug Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable, before Allowance for Credit Loss	$ 810.8	$ 769.4

BUSINESS ACQUISITIONS (Details)

BUSINESS ACQUISITIONS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 19, 2014
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	$ 1,300,000	$ 27,100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(8,400,000)	(94,700,000)
Long-term debt, less current portion	4,054,700,000	5,038,800,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		700,000
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation		2,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	4,100,000	14,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	1,200,000	3,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	3,200,000	72,800,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	2,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	663,100,000	1,258,700,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	671,500,000	1,164,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	13,000,000	53,500,000
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets		32,700,000
Goodwill, Acquired During Period, net of measurement period adjustments	267,500,000	558,100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	1,500,000	1,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	(600,000)	(500,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		(300,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	360,300,000	572,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	$ 20,100,000	12,500,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	13 years 3 months 18 days
Goodwill, net	$ 6,142,500,000	6,123,700,000	$ 5,891,000,000
Payments to Acquire Businesses, Net of Cash Acquired	671,500,000	1,164,000,000	496,900,000
Finite-lived Intangible Assets Acquired	313,900,000	542,300,000	198,500,000
Goodwill, Acquired During Period	296,900,000	598,500,000	298,400,000
Line of Credit Facility, Maximum Borrowing Capacity				$ 1,000,000,000
Revenues	12,161,600,000	11,863,900,000	13,136,100,000
Operating Income (Loss)	725,600,000	1,436,500,000	3,048,600,000
Senior notes due 2020 [Member]
Business Acquisition [Line Items]
Long-term debt, less current portion	500,000,000	500,000,000
Excluding Envigo [Member]
Business Acquisition [Line Items]
Goodwill, Acquired During Period		598,500,000
Other acquirees [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0	0	1,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities			62,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(1,700,000)	(15,400,000)	(75,200,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net			496,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		0	6,600,000
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	4,100,000	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	1,200,000	0	2,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	1,200,000	15,400,000	3,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	72,100,000	300,600,000	572,100,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	73,800,000	285,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	6,500,000	100,000	56,600,000
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	300,000	300,000	3,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	(2,000,000)	(1,300,000)	(10,800,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		0	(3,200,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	26,900,000	172,500,000	198,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	17,900,000	2,300,000
Finite-lived Intangible Assets Acquired	340,800,000
Goodwill, Acquired During Period	18,500,000	126,700,000	298,400,000
2021 acquisitions
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Revenue			11,984,700,000
Business Acquisition, Pro Forma Net Income (Loss)			1,006,800,000
Ascension Acquisition
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory		24,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		(2,900,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		0
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation		2,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		426,700,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		423,800,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		43,500,000
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets		400,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		233,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets		0
Goodwill, Acquired During Period		125,000,000
Measurement Period Adjustments
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	10,600,000	2,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		(2,600,000)
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	0	(100,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	(8,300,000)	100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	(2,300,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(10,600,000)	(2,600,000)
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	0	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	(1,500,000)	0
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets		15,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	600,000	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	(200,000)	2,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		3,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	19,500,000	30,400,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	0	(2,300,000)
Goodwill, Acquired During Period	(29,400,000)	(40,400,000)
PGDx
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory		2,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		(79,000,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		3,300,000
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other		14,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable		3,800,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other		57,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		534,000,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		455,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		9,900,000
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets		17,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets		1,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables		(4,100,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		(2,900,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		136,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets		12,500,000
Goodwill, Acquired During Period		346,800,000
2022 acquisitions
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Revenue			13,325,700,000
Business Acquisition, Pro Forma Net Income (Loss)			$ 2,182,400,000
2023 acquisitions
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Revenue	12,350,100,000	12,126,300,000
Business Acquisition, Pro Forma Net Income (Loss)	397,200,000	$ 1,030,300,000
Jefferson Health
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	110,200,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	110,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	57,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	2,200,000
Goodwill, Acquired During Period	50,800,000
Enzo BioChem
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	112,800,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	112,800,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	400,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	(2,800,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	61,100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	0
Goodwill, Acquired During Period	54,100,000
Providence Health
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	1,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(3,900,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	3,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	113,900,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	110,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	4,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	57,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	0
Goodwill, Acquired During Period	50,700,000
Tufts Medicine
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	157,000,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	157,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	83,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	0
Goodwill, Acquired During Period	73,800,000
Legacy Health
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	107,700,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	107,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	3,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	55,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	0
Goodwill, Acquired During Period	$ 49,000,000
Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life		19 years
Customer Relationships [Member] | Other acquirees [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		15 years
Technology-Based Intangible Assets
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life		15 years
Technology-Based Intangible Assets | Other acquirees [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years
Trade Names [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		10 years
Trade Names [Member] | Other acquirees [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		5 years
Non-compete agreements [Member] | Other acquirees [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		5 years
Non-compete agreement | Other acquirees [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years
Customer List | Other acquirees [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	15 years
Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	12 years 6 months
Finite-lived Intangible Assets Acquired	$ 260,600,000

BUSINESS ACQUISITIONS & DISPO_2

BUSINESS ACQUISITIONS & DISPOSITIONS DISPOSITIONS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Business Combination and Asset Acquisition [Abstract]
Payments to Acquire Businesses, Net of Cash Acquired	$ 671.5	$ 1,164	$ 496.9
Finite-lived Intangible Assets Acquired	313.9	542.3	198.5
Goodwill, Acquired During Period	296.9	598.5	298.4
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	1.3	27.1
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	1.5	1.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	0.6	0.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		0.3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	13	53.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	360.3	572.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	663.1	1,258.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	1.2	3.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	3.2	72.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		0.7
Goodwill, Acquired During Period	296.9	598.5	298.4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	8.4	94.7
Restructuring charges related to contractual obligations associated with leased facilities and other facility related costs		31.1	12
Other acquirees [Member]
Business Combination and Asset Acquisition [Abstract]
Finite-lived Intangible Assets Acquired	340.8
Goodwill, Acquired During Period	18.5	126.7	298.4
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0	0	1.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	0.3	0.3	3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	2	1.3	10.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		0	3.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	6.5	0.1	56.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	26.9	172.5	198.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	72.1	300.6	572.1
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	1.2	0	2.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	1.2	15.4	3.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		0	6.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities			62.2
Goodwill, Acquired During Period	18.5	126.7	298.4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	$ 1.7	$ 15.4	75.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net			$ 496.9

BUSINESS ACQUISITIONS & DISPO_3

BUSINESS ACQUISITIONS & DISPOSITIONS Envigo (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Operating Income (Loss)	$ 725.6	$ 1,436.5	$ 3,048.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		0.3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	1.3	27.1
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	671.5	1,164
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	0.6	0.5
Payments to Acquire Businesses, Net of Cash Acquired	671.5	1,164	496.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	1.5	1.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	13	53.5
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets		32.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	360.3	572.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	663.1	1,258.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	1.2	3.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	3.2	72.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		0.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	$ 8.4	94.7
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	13 years 3 months 18 days
Other acquirees [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		0	3.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	$ 0	0	1.6
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	73.8	285.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	2	1.3	10.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	0.3	0.3	3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	6.5	0.1	56.6
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	26.9	172.5	198.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	72.1	300.6	572.1
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	1.2	0	2.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	1.2	15.4	3.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		0	6.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities			62.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	$ 1.7	$ 15.4	75.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net			$ 496.9
Customer Relationships [Member] | Other acquirees [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		15 years
Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	12 years 6 months

Restructuring and Related Act_3

Restructuring and Related Activities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Restructuring and Related Activities [Abstract]
Number of years restructuring liabilities expected to be paid out over	9 years 8 months 12 days
Net restructuring charges	$ 49.1	$ 54	$ 24
Restructuring charges related to severance and other employee costs	33.4	24.8	12.4
Restructuring Costs and Asset Impairment Charges	22.3
Employee Severance Benefits Related Restructuring Reserve Accrual Adjustment	1.7	1.4	0.3
Facility Related Restructuring Reserve Accrual Adjustment	4.9	0.5	0.2
Restructuring charges related to contractual obligations associated with leased facilities and other facility related costs		31.1	12
Restructuring Reserve	20.6	11.5	5.3
Restructuring Reserve, Current	9.5
Restructuring Reserve, Noncurrent	11.1
Restructuring Charges	55.7	55.9
Restructuring Reserve, Accrual Adjustment	(6.6)	(1.9)
Payments for Restructuring	(40)	(47.8)
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	20.6	11.5	5.3
Net restructuring charges	49.1	54	24
Restructuring charges related to severance and other employee costs	33.4	24.8	12.4
Restructuring Costs and Asset Impairment Charges	22.3
Restructuring Reserve, Accrual Adjustment	(6.6)	(1.9)
Payments for Restructuring	40	47.8
Restructuring Charges	55.7	55.9
Employee Severance [Member] | LabCorp Diagnostics [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	7.6	2.1	3.7
Restructuring Charges	33.4	24.8
Restructuring Reserve, Accrual Adjustment	(1.7)	(1.4)
Payments for Restructuring	26.2	25
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	7.6	2.1	3.7
Restructuring Reserve, Accrual Adjustment	(1.7)	(1.4)
Payments for Restructuring	(26.2)	(25)
Restructuring Charges	33.4	24.8
Facility Closing [Member] | LabCorp Diagnostics [Member]
Restructuring and Related Activities [Abstract]
Restructuring Reserve	13	9.4	1.6
Restructuring Charges	22.3	31.1
Restructuring Reserve, Accrual Adjustment	(4.9)	(0.5)
Payments for Restructuring	13.8	22.8
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	13	9.4	$ 1.6
Restructuring Reserve, Accrual Adjustment	(4.9)	(0.5)
Payments for Restructuring	(13.8)	(22.8)
Restructuring Charges	$ 22.3	$ 31.1

LEASES (Details)

LEASES (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	15 years
Lessee, Operating Lease, Renewal Term	15 years
Variable Lease, Payment	$ 32,700,000	$ 27,900,000	$ 28,400,000
Short term lease
Lessee, Lease, Description [Line Items]
Operating Lease, Expense		$ 22,200,000	$ 19,500,000
Short term lease
Lessee, Lease, Description [Line Items]
Operating Lease, Expense	$ 31,900,000

LEASES - Lease Cost (Details)

LEASES - Lease Cost (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Operating Lease, Cost	$ 202.6	$ 198.1
Finance Lease, Right-of-Use Asset, Amortization	7.1	8
Finance Lease, Interest Expense	4.8	5.2
Lease, Cost	$ 11.9	$ 13.2

LEASES - Supplemental Cash Flow

LEASES - Supplemental Cash Flow (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Operating Lease, Payments	$ (209,700,000)	$ (200,200,000)
Finance Lease, Interest Payment on Liability	(4,800,000)	(5,200,000)
Finance Lease, Principal Payments	(12,600,000)	(12,300,000)
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	106,400,000	159,200,000
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	$ 2,300,000	$ 0

LEASES - Supplemental Balance S

LEASES - Supplemental Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Operating Lease, Right-of-Use Asset	$ 737.1	$ 738.1
Operating Lease, Liability, Current	165.8	163.8
Total maturities, due beyond one year	648.9	652.9
Operating Lease, Liability	814.7	816.7
Finance Lease, Right-of-Use Asset	69.5	74.9
Finance Lease, Liability, Current	6.4	6
Total maturities, due beyond one year	78.6	83.6
Finance Lease, Liability	$ 85	$ 89.6
Operating Lease, Weighted Average Remaining Lease Term	8 years 4 months 24 days	9 years
Finance Lease, Weighted Average Remaining Lease Term	14 years 8 months 12 days	15 years 7 months 6 days
Operating Lease, Weighted Average Discount Rate, Percent	4.10%	3.60%
Finance Lease, Weighted Average Discount Rate, Percent	5.30%	5.50%
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, plant and equipment, net	Property, plant and equipment, net
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets, net	Other assets, net

LEASES - Maturity of Leases (De

LEASES - Maturity of Leases (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Operating Lease, Liability [Abstract]
2024	$ 200.1
2025	161.2
2026	114.1
2027	86.1
2028	70.7
Thereafter	330.1
Total lease payments	962.3
Less imputed interest	(147.6)
Less current portion	(165.8)	$ (163.8)
Total maturities, due beyond one year	648.9	652.9
Finance Lease Liability [Abstract]
2024	11.3
2025	9.2
2026	8.6
2027	8.2
2028	7.6
Thereafter	78.3
Total lease payments	123.2
Less imputed interest	(38.2)
Less current portion	(6.4)	(6)
Total maturities, due beyond one year	$ 78.6	$ 83.6

PROPERTY, PLANT AND EQUIPMENT_3

PROPERTY, PLANT AND EQUIPMENT, NET (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Depreciation, Depletion and Amortization	$ 577,300,000	$ 537,200,000	$ 577,000,000
Property, plant and equipment, net
Gross property, plant and equipment	5,816,900,000	5,378,500,000
Less accumulated depreciation	(2,905,100,000)	(2,584,400,000)
Property, plant and equipment, net	2,911,800,000	2,794,100,000
Software depreciation	76,600,000	75,700,000	73,700,000
Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciation, Depletion and Amortization	361,100,000	343,600,000	$ 347,600,000
Land [Member]
Property, plant and equipment, net
Gross property, plant and equipment	98,800,000	98,500,000
Buildings and building improvements [Member]
Property, plant and equipment, net
Gross property, plant and equipment	1,083,800,000	1,009,800,000
Machinery and equipment [Member]
Property, plant and equipment, net
Gross property, plant and equipment	2,008,000,000	1,820,400,000
Software and Software Development Costs [Member]
Property, plant and equipment, net
Gross property, plant and equipment	924,700,000	811,600,000
Leasehold improvements [Member]
Property, plant and equipment, net
Gross property, plant and equipment	515,800,000	484,000,000
Furniture and Fixtures [Member]
Property, plant and equipment, net
Gross property, plant and equipment	106,500,000	109,600,000
Construction in progress [Member]
Property, plant and equipment, net
Gross property, plant and equipment	342,200,000	306,500,000
Equipment under capital leases [Member]
Property, plant and equipment, net
Gross property, plant and equipment	$ 737,100,000	$ 738,100,000

GOODWILL AND INTANGIBLE ASSET_2

GOODWILL AND INTANGIBLE ASSETS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 219,800,000	$ 193,600,000	$ 229,500,000
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Asset		68,300,000
Finite-Lived Intangible Assets, Future Amortization Expense
Estimated amortization expense, 2013	235,400,000
Estimated amortization expense, 2014	225,700,000
Estimated amortization expense, 2015	216,800,000
Estimated amortization expense, 2016	205,500,000
Estimated amortization expense, 2017	197,300,000
Estimated amortization expense, Thereafter	1,675,000,000
Goodwill, Impairment Loss	333,600,000	260,000,000
Goodwill and Intangible Asset Impairment	349,000,000	261,700,000	$ 0
Goodwill Impairment, Cumulative	648,500,000
Covance Drug Development [Member]
Finite-Lived Intangible Assets, Future Amortization Expense
Goodwill, Impairment Loss	333,600,000	260,000,000
Goodwill and Intangible Asset Impairment	333,600,000
Covance Drug Development [Member] | Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets, Future Amortization Expense
Amortization	30.8
LabCorp Diagnostics [Member]
Finite-Lived Intangible Assets, Future Amortization Expense
Goodwill, Impairment Loss	$ 0	$ 0

GOODWILL AND INTANGIBLE ASSET_3

GOODWILL AND INTANGIBLE ASSETS - SCHEDULE OF GOODWILL (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Line Items]
Goodwill	$ 6,142,500,000	$ 6,123,700,000	$ 5,891,000,000
Adjustments to goodwill	55,500,000	(105,800,000)
Goodwill, Acquired During Period	296,900,000	598,500,000	298,400,000
Goodwill, Impairment Loss	(333,600,000)	(260,000,000)
Goodwill [Roll Forward]
Balance as of January 1	6,123,700,000	5,891,000,000
Adjustments to goodwill	55,500,000	(105,800,000)
Goodwill, net	6,142,500,000	6,123,700,000	5,891,000,000
LabCorp Diagnostics [Member]
Goodwill [Line Items]
Goodwill	4,813,900,000	4,533,500,000	4,046,200,000
Adjustments to goodwill	(16,500,000)	(70,600,000)
Goodwill, Acquired During Period	296,900,000	557,900,000
Goodwill, Impairment Loss	0	0
Goodwill [Roll Forward]
Balance as of January 1	4,533,500,000	4,046,200,000
Adjustments to goodwill	(16,500,000)	(70,600,000)
Goodwill, net	4,813,900,000	4,533,500,000	4,046,200,000
Covance Drug Development [Member]
Goodwill [Line Items]
Goodwill	1,328,600,000	1,590,200,000	1,844,800,000
Adjustments to goodwill	72,000,000	(35,200,000)
Goodwill, Acquired During Period	0	40,600,000
Goodwill, Impairment Loss	(333,600,000)	(260,000,000)
Goodwill [Roll Forward]
Balance as of January 1	1,590,200,000	1,844,800,000
Adjustments to goodwill	72,000,000	(35,200,000)
Goodwill, net	$ 1,328,600,000	$ 1,590,200,000	$ 1,844,800,000

GOODWILL AND INTANGIBLE ASSET_4

GOODWILL AND INTANGIBLE ASSETS - COMPONENTS OF IDENTIFIABLE INTANGIBLE ASSETS (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount	$ 5,058.4	$ 4,593.3
Accumulated Amortization	(1,716.4)	(1,469.7)
Net Carrying Amount	3,342	3,123.6
Customer Relationships [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount		3,490
Accumulated Amortization		(1,169.7)
Net Carrying Amount		2,320.3
Patents, licenses and technology [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount		520.4
Accumulated Amortization		(243.3)
Net Carrying Amount		277.1
Non-compete agreements [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount		80.1
Accumulated Amortization		(46.8)
Net Carrying Amount		33.3
Trade names [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount		16.4
Accumulated Amortization		(3.5)
Net Carrying Amount		12.9
Canadian licenses [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount		468.7
Accumulated Amortization		0
Net Carrying Amount		468.7
Media Content
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount		5.1
Accumulated Amortization		(4.2)
Net Carrying Amount		0.9
Patents, licenses and technology [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount	526.6
Accumulated Amortization	(273.3)
Net Carrying Amount	253.3
Customer Relationships [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount	3,868.6
Accumulated Amortization	(1,367.2)
Net Carrying Amount	2,501.4
Use Rights [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount	3.5	3.5
Accumulated Amortization	(2.7)	(2.2)
Net Carrying Amount	0.8	1.3
Trade names [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount	16.4
Accumulated Amortization	(6.1)
Net Carrying Amount	10.3
Non-compete agreements [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount	130.3
Accumulated Amortization	(60.4)
Net Carrying Amount	69.9
Canadian licenses [Member]
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount	498.8
Accumulated Amortization	0
Net Carrying Amount	498.8
In Process Research and Development
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount	9.1	9.1
Accumulated Amortization	(2)	0
Net Carrying Amount	7.1	$ 9.1
Media Content
Finite-Lived Intangible Assets [Abstract]
Gross Carrying Amount	5.1
Accumulated Amortization	(4.7)
Net Carrying Amount	$ 0.4

GOODWILL AND INTANGIBLE ASSET_5

GOODWILL AND INTANGIBLE ASSETS - SUMMARY OF ACQUIRED AMORTIZABLE INTANGIBLE ASSETS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 313.9	$ 542.3	$ 198.5
Weighted average amortization period (in years)	13 years 3 months 18 days
Gross Carrying Amount	$ 5,058.4	4,593.3
In Process Research and Development
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	9.1	9.1
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 260.6
Weighted average amortization period (in years)	12 years 6 months
Gross Carrying Amount		3,490
Patents, licenses and technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		520.4
Non-compete agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 53.3
Weighted average amortization period (in years)	9 months 18 days
Gross Carrying Amount		80.1
Trade names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 16.4

ACCRUED EXPENSES AND OTHER (Det

ACCRUED EXPENSES AND OTHER (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Accrued expenses and other [Abstract]
Employee compensation and benefits	$ 431.4	$ 444.6
Accrued taxes payable	127.5	105.6
Other	245.1	236.8
Total accrued expenses and other	$ 804	$ 787

DEBT - SCHEDULE OF SHORT-TERM D

DEBT - SCHEDULE OF SHORT-TERM DEBT (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Jun. 03, 2019
Short-term Debt [Line Items]
2019 Term Loan			$ 850
Debt, Current	$ 999.8	$ 301.3
2.30% senior notes due 2024	0	400
Senior notes due 2024	0	600
Short term debt issue costs
Short-term Debt [Line Items]
Short term debt issuance costs	(1.3)	(0.4)
Note payable, current
Short-term Debt [Line Items]
Notes Payable, Current	1.1	1.7
Senior Notes due 2023
Short-term Debt [Line Items]
4.00% Senior notes due 2023	0	300
Senior Notes
Short-term Debt [Line Items]
2.30% senior notes due 2024 short term	400
2.30% senior notes due 2024		0
Short-Term Debt
Short-term Debt [Line Items]
3.25% Senior notes due 2024 short term	$ 600
Senior notes due 2024		$ 0

DEBT - SCHEDULE OF LONG-TERM DE

DEBT - SCHEDULE OF LONG-TERM DEBT (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 19, 2014
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 1,001.1
Credit Facility Option to Increase			$ 500
Long-term debt, less current portion	4,054.7	$ 5,038.8
2.30% senior notes due 2024	0	400
2.95% senior notes due 2029	650	650
Senior notes due 2027	600	600
4.70 % Senior notes due 2045	900	900
Senior notes due 2024	0	600
3.60% Senior notes due 2025	1,000	1,000
1.55% senior notes due 2026	500	500
Notes Payable, Noncurrent	0.6	2.3
Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Two	1,000
Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Four	500
Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Five	600
Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal in Year Five	0
Long-term Debt and Capital Lease Obligations, Maturities, Repayments of Principal after Year Five	1,981
Long term debt, future minimum payments, interest included in payments	5,082.1
Short term debt excluding debt issuance costs	1,001.1
Long term debt excluding debt issuance costs	4,081
Debt, Current	$ (999.8)	$ (301.3)

DEBT - CREDIT FACILITIES (Detai

DEBT - CREDIT FACILITIES (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jun. 03, 2019	Dec. 19, 2014
Line of Credit Facility [Line Items]
Long term debt issuance costs	$ 26.3	$ 33.8
2019 Term Loan				$ 850
Repayments of Other Long-term Debt	0	0	$ 375
Long-term debt, less current portion	$ 4,054.7	$ 5,038.8
Line of Credit Facility, Maximum Borrowing Capacity					$ 1,000
Credit Facility Option to Increase					500
Credit Facility, Maximum Swing Line Borrowings					100
Line of Credit Facility, Commitment Fee Description	0.10% to 0.225%
Letters of Credit Outstanding, Amount	$ 91.3
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate at Period End	6.44%
Credit Facility, Maximum Letters of Credit					$ 150

DEBT - COVERTIBLE SUBORDINATED

DEBT - COVERTIBLE SUBORDINATED NOTES (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Notes Payable, Noncurrent	$ 0.6	$ 2.3
Long-term debt, less current portion	4,054.7	5,038.8
Senior notes due 2024	0	600
Foreign Currency Contract, Asset, Fair Value Disclosure	(109)	(45.7)
Debt, Current	999.8	301.3
Senior notes due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	$ 600	$ 600

DEBT - SENIOR NOTES (Details)

DEBT - SENIOR NOTES (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 19, 2014
Debt Instrument [Line Items]
Debt, Current	$ (999.8)	$ (301.3)
Credit Facility, Maximum Swing Line Borrowings			$ 100
Long-term debt, less current portion	4,054.7	5,038.8
2.70% senior notes due 2031	500	420.3
Intangible assets, net	3,342	3,123.6
1.55% senior notes due 2026	500	500
Interest Rate Swap [Member]
Debt Instrument [Line Items]
2.70% senior notes due 2031	430.4
In Process Research and Development
Debt Instrument [Line Items]
Intangible assets, net	7.1	9.1
Senior notes due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	500	500
Senior notes due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	600	$ 600
Senior notes due 2024 | 2022 Swap Agreements
Debt Instrument [Line Items]
Derivative, Notional Amount	300
Senior notes due 2022 | 2018 Swap Agreements
Debt Instrument [Line Items]
Derivative, Notional Amount	$ 300

PREFERRED STOCK AND COMMON SH_3

PREFERRED STOCK AND COMMON SHAREHOLDERS' EQUITY (Details) - USD ($) $ / shares in Units, $ in Millions				1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 13, 2024	Feb. 27, 2024	Jan. 12, 2024	Dec. 31, 2021	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Stockholders' Equity Note [Abstract]
Common stock, par value per share (in dollars per share)					$ 0.10		$ 0.10
Preferred stock, shares authorized (in shares)					30,000,000		30,000,000
Preferred stock, par value per share (in dollars per share)					$ 0.10		$ 0.10
Rollforward of common shares issued [Abstract]
Common shares issued, beginning balance (in shares)						88,200,000	88,200,000	93,100,000	97,500,000
Common stock issued under employee stock plans (in shares)							500,000	700,000	800,000
Common shares repurchased (in shares)				(2,700,000)			(4,800,000)	(5,600,000)	(5,200,000)
Common shares issued, ending balance (in shares)				93,100,000	83,900,000		83,900,000	88,200,000	93,100,000
Share repurchase program [Abstract]
Purchase of common stock							$ (1,009)	$ (1,100)	$ (1,668.5)
Outstanding common stock repurchase authorization					$ 530.4		530.4
Foreign Currency Translation Adjustments
Foreign Currency Translation Adjustments, balance				$ (125.9)	(47.6)		(47.6)	(462.3)	(125.9)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss), before Reclassification and Tax							183.1	(335.5)
Current year adjustments, Foreign Currency Translation Adjustments							183.1	(336.4)	(104.6)
Tax effect of adjustments, Foreign Currency Translation Adjustments							0	0
Net Benefit Plan Adjustments
Net Benefit Plan Adjustments, balance						$ (30.9)	(30.9)	(66)
Tax effect of adjustments, Net Benefit Plan Adjustments							(1.8)	(9.7)
Net Benefit Plan Adjustments, balance				(66)	(11.7)		(11.7)	(30.9)	(66)
Accumulated Other Comprehensive Earnings
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax							(4.6)	(5.5)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax							(4.6)	(4.6)
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax							30.1	52.5
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, before Tax							0	(0.9)
Other Comprehensive Income (Loss), before Reclassifications, before Tax							213.2	(283)
Tax effect of adjustments, Accumulated Other Comprehensive Earnings							(1.8)	(9.7)	$ (17.1)
Accumulated Other Comprehensive Earnings, balance					$ 59.3		$ 59.3	$ 493.2		$ 161.9
Common stock, shares authorized (in shares)					265,000,000		265,000,000
Treasury Stock Acquired, Average Cost Per Share							$ 206.85	$ 233.48	$ 282.05
Payments for Repurchase of Common Stock				$ 1,000			$ 1,000	$ 1,100	$ 1,668.5
Stock Repurchase Program, Authorized Amount					$ 2,500		2,500
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax					(59.3)		(59.3)	(493.2)		$ (161.9)
Other Comprehensive Income (Loss), before Reclassifications, before Tax							$ 213.2	$ (283)
Stock Repurchased and Retired During Period, Shares				2,700,000			4,800,000	5,600,000	5,200,000
Stock Repurchase Program, Authorized Amount					2,500		$ 2,500
Outstanding common stock repurchase authorization					530.4		$ 530.4
Treasury Stock Acquired, Average Cost Per Share							$ 206.85	$ 233.48	$ 282.05
Accelerated Share Repurchases, Settlement (Payment) or Receipt				$ 1,000	1,000		$ 1,000	$ 1,100	$ 1,000
Sales and Excise Tax Payable					$ 9		9
Stockholders' Equity Note, Spinoff Transaction							(1,732)
Stock Repurchased During Period, Shares					1,100,000	3,700,000
2022 Share Repurchases
Rollforward of common shares issued [Abstract]
Common shares repurchased (in shares)								(4,700,000)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stock Repurchased and Retired During Period, Shares								4,700,000
Subsequent Event
Accumulated Other Comprehensive Income (Loss) [Line Items]
Dividends Payable, Date Declared			Jan. 12, 2024
Dividends Payable, Amount Per Share			$ 720,000
Dividends Payable, Date to be Paid	Mar. 13, 2024
Dividends Payable, Date of Record		Feb. 27, 2024
2022 ASR Settlement
Rollforward of common shares issued [Abstract]
Common shares repurchased (in shares)								(900,000)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stock Repurchased and Retired During Period, Shares								900,000
Pension Plan [Member]
Foreign Currency Translation Adjustments
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), after Tax							(10.9)	$ (3.1)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), after Tax							(10.9)	(3.1)
Foreign Currency Gain (Loss)
Foreign Currency Translation Adjustments
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), after Tax							0	0
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), after Tax							0	0
AOCI Attributable to Parent [Member]
Share repurchase program [Abstract]
Purchase of common stock							0	0	0
Accumulated Other Comprehensive Earnings
Accumulated Other Comprehensive Earnings, balance				191.9	$ 59.3		59.3	493.2	191.9
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax				$ (191.9)	$ (59.3)		(59.3)	(493.2)	$ (191.9)
Dividends							0	$ 0
Stockholders' Equity Note, Spinoff Transaction							$ 238

INCOME TAXES (Details)

INCOME TAXES (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Valuation Allowance [Line Items]
Undistributed Earnings of Foreign Subsidiaries	$ 607.6	$ 927.4
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense	$ (8.9)	$ (10.2)	$ (6.8)
Federal			$ 25.2
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent	10.80%	3.70%	0%
Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-Based Payment Arrangement, Percent	1.70%	1.20%	0.30%
Effective Income Tax Rate Reconciliation, Deduction, Other, Percent	(2.60%)	0%	0%
Unrecognized income tax benefits that would impact effective tax rate	$ 0	$ 0	$ 0.9
Federal tax loss carryovers	$ 127
Operating Loss Carryforwards, Limitations on Use	80
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent	2.20%	0.70%	0.70%
Effective Income Tax Rate Reconciliation, Tax Credit, Percent	(3.80%)	(5.40%)	(0.10%)
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	2.70%	(2.40%)	(0.10%)
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	$ 0.2
Foreign Tax Loss Carryovers Expire by 2043	14.5
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction	7.8	$ 8.1
Pre-tax income [Abstract]
Domestic	504	1,097.9	$ 2,455
Foreign	64.9	139.5	432.6
Current tax expense:
Federal	183.1	150.8	500
State	38.9	25.4	156.5
Foreign	44.6	34	71.9
Total current income taxes	266.6	210.2	728.4
Deferred Federal Income Tax Expense (Benefit)	(63.1)	15.8	(36.7)
Deferred tax expense/(benefit):
Federal			25.2
State	(31.6)	0.6	(9)
Foreign	16.6	7.3	7.3
Deferred Income Tax Expense (Benefit)	(78.1)	23.7	(38.4)
Total income tax provision	188.5	$ 233.9	$ 690
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	442.8
Operating Loss Carryforwards, Valuation Allowance	403
Federal and State Attribute Carryforwards	114.4
Federal and State Attribute Carryforward Valuation Allowance	$ 69.2
Federal statutory tax rate reconciliation [Abstract]
Statutory U.S. rate	21%	21%	21%
State and local income taxes, net of U.S. federal income tax effect	4%	4.20%	3.90%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent	2.20%	0.70%	0.70%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent	10.80%	3.70%	0%
Other	1.50%	(2.70%)	(0.40%)
Effective rate	33.10%	18.90%	23.90%
Deferred tax assets:
Accounts receivable	$ 27.9	$ 19.4
Employee compensation and benefits	81.7	96.5
Deferred Tax Asset, Right Of Use Asset	191.4	182.6
Acquisition and restructuring reserves	9.2	7
Deferred Tax Assets, Tax Credit Carryforwards, Research	142.9	44.1
Tax loss carryforwards	246.9	241.9
Deferred Tax Assets, Other	95.1	95.1
Total deferred tax assets	795.1	686.6
Less: valuation allowance	(150.2)	(151.3)	$ (149.2)	$ (167.6)
Deferred tax assets, net of valuation allowance	644.9	535.3
Deferred tax liabilities:
Deferred Tax Liabilities, Leasing Arrangements	(175.3)	(170.2)
Intangible assets	(614.8)	(605.1)
Property, plant and equipment	(163.5)	(166.5)
Deferred Tax Liabilities, Other	(66.2)	(62.7)
Total gross deferred tax liabilities	(374.9)	(469.2)
Deferred Tax Liabilities, Gross	(1,019.8)	(1,004.5)
Foreign tax loss carryovers	117.2
Foreign Tax Loss Carryover with Valuation Allowance	7.9
Foreign Tax Loss Carryovers Expire in 2034	444.3
Deferred Tax Assets, Capital Loss Carryforwards	27.4
Federal tax loss carryovers	127
Gross unrecognized income tax benefits	29.9	37.5	39.6	$ 18.6
Accrued interest and penalties related to unrecognized income tax benefits	0.1	2.3
Income Tax Examination, Penalties Expense	0	0.8	0
Reversal of Accrued Income Tax Penalties And Interest	1.8	0	1.1
Reconciliation of unrecognized tax benefits [Roll Forward]
Balance as of January 1	37.5	39.6	18.6
Increase in reserve for tax positions taken in the current year	1.8	1.8	0
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions	10.4	10.6	31.1
Unrecognized Tax Benefits Increase in Reserve From Acquisition		0	(8.1)
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	(4)
Decrease in reserve as a result of settlements	(7.2)	(10.4)	0
Decrease in reserve as a result of lapses in the statute of limitations	(8.6)	(4.1)	(2)
Balance as of December 31	29.9	37.5	39.6
Unrecognized income tax benefits that would impact effective tax rate	0	0	0.9
Income (Loss) from Continuing Operations Before Income Taxes and Noncontrolling Interest	568.9	1,237.4	2,887.6
Post 2017
Valuation Allowance [Line Items]
Federal tax loss carryovers	179.1
Deferred tax liabilities:
Federal tax loss carryovers	179.1
Reduction in Taxes
Valuation Allowance [Line Items]
Unrecognized income tax benefits that would impact effective tax rate	29.9	37.5	38.7
Reconciliation of unrecognized tax benefits [Roll Forward]
Unrecognized income tax benefits that would impact effective tax rate	29.9	$ 37.5	$ 38.7
Federal Loss Carryover [Domain]
Valuation Allowance [Line Items]
Federal	8.4
Deferred tax expense/(benefit):
Federal	$ 8.4

STOCK COMPENSATION PLANS (Detai

STOCK COMPENSATION PLANS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangements by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	6 years	6 years	6 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Grant Date Intrinsic Value	$ 72.27	$ 68.35	$ 55.75
Number of shares purchased by eligible employees	300,000	200,000	200,000
Fair value of the employee's purchase right	$ 49.19	$ 62.50	$ 59.89
Risk free interest rate	3.40%	2%	0.60%
Expected volatility	29.80%	28.60%	28.60%
Expected dividend yield	1.40%	0.90%
Shares of common stock authorized for issuance under the employee stock purchase plan	1,800,000
The employee stock purchase plan permits employees to purchase shares of common stock at a certain percentage of the market price (in hundredths)	85%
Expense related to the Company's employee stock purchase plan	$ 13,800,000	$ 14,800,000	$ 14,600,000
Unrecognized compensation cost related to nonvested restricted stock and performance share-based compensation arrangements	$ 83,000,000
Performance share awards, vesting conditions	Performance share awards are subject to certain earnings per share, revenue, and total shareholder return targets
Restricted stock, vesting increment	one-third increments beginning on the first anniversary of the grant
Cash received by the Company	$ 2,900,000	7,100,000	6,800,000
Share-based Payment Arrangement, Exercise of Option, Tax Benefit	700,000	1,800,000	1,700,000
Aggregate intrinsic value	$ 700,000	8,200,000	13,400,000
Unrecognized compensation cost weighted average expected future recognition period (in years)	1 year 10 months 24 days
Restricted stock and performance share compensation expense	$ 111,100,000	97,700,000	114,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	9,400,000
Shares available for grant under the Company's stock option plans	3,500,000
Stock option plan expense	$ 3,800,000	$ 4,300,000	$ 3,600,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangements by Share-based Payment Award
Risk free interest rate	5%	1.30%	0.10%
Expected volatility	30%	30%	30%
Expected dividend yield	1.40%	0.90%	0%
Restricted Stock and Performance Shares [Member]
Share-based Compensation Arrangements by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 235.27
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	1,000,000	1,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 248.41	$ 231.30
Number of options granted	500,000
Weighted-average grant date fair value, granted	$ 224.11
Number of options vested	(500,000)
Weighted-average grant date fair value, vested	$ 208.71
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(100,000)
Stock Options [Member]
Share-based Compensation Arrangements by Share-based Payment Award
Aggregate intrinsic value, exercisable options	$ 31,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	600,000	500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 174.45	$ 169.31
Number of options granted	100,000
Weighted-average exercise price per option granted	$ 219.83
Weighted-average remaining contractual term of options outstanding (in years)	6 years
Aggregate intrinsic value of options outstanding	$ 32,200,000
Number of options exercisable	500,000
Weighted-average exercise price per exercisable option	$ 159.05
Weighted-average remaining contractual term, exercisable options (in years)	5 years 4 months 24 days

(Details)

(Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value		$ 817
Initial Damages
Loss Contingencies [Line Items]
Loss Contingency, Damages Awarded, Value		$ 272
Enhanced Damages
Loss Contingencies [Line Items]
Loss Contingency, Damages Awarded, Value	$ 100

COMMITMENTS AND CONTINGENT LI_2

COMMITMENTS AND CONTINGENT LIABILITIES (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Loss Contingency, Damages Sought, Value	$ 817

PENSION AND POSTRETIREMENT PL_3

PENSION AND POSTRETIREMENT PLANS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	$ 400,000
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	1,000,000
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	600,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	$ 500,000
Maximum deferral percentage of annual base salary	50%
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	$ 300,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	300,000
Tax effect of adjustments, Net Benefit Plan Adjustments	(1,800,000)	$ (9,700,000)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (59,300,000)	$ (493,200,000)		$ (161,900,000)
Discount rate for the Company Plan	5.10%	5.50%
Defined Benefit Plan, Interest Cost	$ 200,000	$ 100,000	$ 100,000
Net amortization and deferral	0	(200,000)	(300,000)
Defined benefit plan costs	200,000	300,000	400,000
Defined Benefit Plan, Benefit Obligation	3,600,000	3,900,000	5,200,000
Actuarial (gain) loss	(200,000)	(900,000)
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(300,000)	(500,000)
Defined Benefit Plan, Plan Assets, Amount	335,900,000	301,200,000
Unamortized net gain included in accumulated other comprehensive earnings	(800,000)	(200,000)
Net amortization and deferral	0	200,000	300,000
Defined benefit plan costs	200,000	300,000	400,000
Defined Benefit Plan, Benefit Obligation, Benefits Paid	300,000	500,000
Defined Contribution Plan Total Expense	167,600,000	128,200,000	$ 111,200,000
Defined Benefit Plan, Expected Future Employer Contributions, Current Fiscal Year	16,800,000
Deferred Compensation Liability, Classified, Noncurrent	$ 107,400,000	96,900,000
Maximum deferral percentage of annual cash incentive pay	100%
Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	$ 17,600,000
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	97,800,000
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	16,400,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	16,200,000
Defined Benefit Plan, Funded (Unfunded) Status of Plan	$ 9,800,000	$ (22,800,000)
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	4%	2.10%	1.10%
Defined Benefit Plan, Accumulated Benefit Obligation	$ 345,700,000	$ 319,900,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	18,000,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	$ 18,300,000
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase	2%	2%	2%
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)	$ 16,400,000	$ 54,200,000
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)	$ 16,300,000	$ (48,200,000)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase	2%	2%
Discount rate for the Company Plan	4.30%	4.80%
Weighted average expected long-term rate of return for other assets (in hundredths)	5.30%	3.60%	3.10%
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	$ 0	$ 1,100,000	$ 0
Service cost	1,400,000	2,400,000	2,200,000
Defined Benefit Plan, Interest Cost	15,200,000	9,100,000	7,200,000
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	(16,700,000)	(15,800,000)	(14,300,000)
Net amortization and deferral	(100,000)	(800,000)	(1,900,000)
Defined benefit plan costs	0	(4,600,000)	(3,000,000)
Defined Benefit Plan, Benefit Obligation	345,700,000	319,900,000	569,800,000
Actuarial (gain) loss	7,000,000	(187,700,000)
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(14,200,000)	(19,500,000)
Defined Benefit Plan, Plan Assets, Amount	335,900,000	301,200,000	485,200,000
Unamortized net gain included in accumulated other comprehensive earnings	19,100,000	22,600,000
Net amortization and deferral	100,000	800,000	1,900,000
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	16,700,000	15,800,000	14,300,000
Defined benefit plan costs	0	(4,600,000)	$ (3,000,000)
Defined Benefit Plan, Benefit Obligation, Benefits Paid	14,200,000	19,500,000
Employer contributions	14,100,000	13,800,000
Actual return on plan assets	18,000,000	(134,700,000)
Funded status	(9,800,000)	22,800,000
Defined Benefit Plan, Other Cost (Credit)	700,000
Pension Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Other Cost (Credit)	2,200,000
Pension Plan [Member] | Foreign Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Other Cost (Credit)	3,100,000
Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	21,600,000
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	92,200,000
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	21,800,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	22,400,000
Defined Benefit Plan, Funded (Unfunded) Status of Plan	$ (36,600,000)	$ (32,700,000)
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	5.50%	2.80%	2.40%
Defined Benefit Plan, Accumulated Benefit Obligation	$ 231,900,000	$ 259,500,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	20,800,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	21,100,000
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)	0	0
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)	$ 0	$ 0
Discount rate for the Company Plan	5.10%	5.50%
Expected long term rate of return for the Company Plan	6%	4.50%	6%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Weighted-Average Interest Crediting Rate	4%	4%	4%
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	$ (10,900,000)	$ (4,100,000)	$ (3,700,000)
Service cost	3,900,000	2,800,000	3,900,000
Defined Benefit Plan, Interest Cost	12,300,000	9,100,000	8,300,000
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	(11,600,000)	(12,900,000)	(17,300,000)
Net amortization and deferral	(4,500,000)	(4,600,000)	(10,000,000)
Defined benefit plan costs	20,000,000	7,700,000	8,600,000
Defined Benefit Plan, Benefit Obligation	231,900,000	259,500,000	333,300,000
Actuarial (gain) loss	11,700,000	(58,400,000)
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(55,500,000)	(27,300,000)
Defined Benefit Plan, Plan Assets, Amount	195,300,000	226,800,000	299,900,000
Unamortized net gain included in accumulated other comprehensive earnings	47,200,000	60,900,000
Net amortization and deferral	4,500,000	4,600,000	10,000,000
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	11,600,000	12,900,000	17,300,000
Defined benefit plan costs	20,000,000	7,700,000	8,600,000
Defined Benefit Plan, Benefit Obligation, Benefits Paid	55,500,000	27,300,000
Employer contributions	0	0
Actual return on plan assets	21,600,000	(48,200,000)
Funded status	36,600,000	32,700,000
Defined Benefit Plan, Other Cost (Credit)	400,000
UK Plan
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(13,700,000)	(14,900,000)
Defined Benefit Plan, Benefit Obligation, Benefits Paid	13,700,000	14,900,000
Other Liabilities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Benefit Obligation	3,000,000	3,300,000
Other Liabilities [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(30,600,000)	(29,200,000)
Funded status	30,600,000	29,200,000
Other Liabilities [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(34,100,000)	(32,500,000)
Funded status	34,100,000	32,500,000
Accrued Liabilities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Benefit Obligation	600,000	600,000
Accrued Liabilities [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(700,000)	(600,000)
Funded status	700,000	600,000
Accrued Liabilities [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(2,500,000)	(2,400,000)
Funded status	$ 2,500,000	2,400,000
Other Investments | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	13.70%
Other Investments | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	1.70%
Other Investments | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25%
Other Investments | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	5%
Other Investments | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10%
Other Investments | Minimum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Equity Securities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	13%
Equity Securities [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	26.60%
Equity Securities [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	19.80%
Equity Securities [Member] | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	35%
Equity Securities [Member] | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25.50%
Equity Securities [Member] | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25%
Fixed Income Securities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	67%
Debt Securities [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	40.80%
Debt Securities [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	76.40%
Debt Securities [Member] | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	45%
Debt Securities [Member] | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	87%
Debt Securities [Member] | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	35%
Life and Annuity Insurance Product Line [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 0
Life and Annuity Insurance Product Line [Member] | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	20%
Life and Annuity Insurance Product Line [Member] | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Life and Annuity Insurance Product Line [Member] | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10%
Life and Annuity Insurance Product Line [Member] | Minimum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Real Estate Funds [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	3.30%
Real Estate Funds [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.50%
Defined Benefit Plan, Actual Asset Allocation	2.10%
Real Estate Funds [Member] | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10%
Real Estate Funds [Member] | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	4.30%
Real Estate Funds [Member] | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Variable Annuity [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	15.70%
Variable Annuity [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	0%
Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 99,000,000	53,100,000
Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	46,200,000	3,000,000
Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	3,300,000	3,900,000
Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	236,900,000	248,100,000
Fair Value Measured at Net Asset Value Per Share | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	192,000,000	222,900,000
Fair Value Measured at Net Asset Value Per Share | Real Estate Funds [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	4,000,000	5,000,000
Fair Value Measured at Net Asset Value Per Share | Equity Funds | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	27,300,000	39,600,000
Fair Value Measured at Net Asset Value Per Share | International - developed [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	11,400,000	17,000,000
Fair Value Measured at Net Asset Value Per Share | U.S. fixed income [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	149,300,000	161,300,000
Fair Value Measured at Net Asset Value Per Share | Mutual Funds [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	236,900,000	248,100,000
Fair Value, Inputs, Level 3 [Member] | Life and Annuity Insurance Product Line [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	52,800,000	50,100,000	$ 81,300,000
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Actual Return (Loss) on Plan Assets Still Held	$ 2,700,000	$ (31,200,000)

PENSION AND POSTRETIREMENT PL_4

PENSION AND POSTRETIREMENT PLANS - FAIR VALUE OF PLAN ASSETS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Benefit Obligation	$ 3,600,000	$ 3,900,000	$ 5,200,000
Defined Benefit Plan, Plan Assets, Amount	335,900,000	301,200,000
Defined Benefit Plan, Benefit Obligation, Benefits Paid	300,000	500,000
Defined Benefit Plan, Interest Cost	200,000	100,000	100,000
Actuarial (gain) loss	(200,000)	(900,000)
Defined-benefit plan costs	(200,000)	(300,000)	(400,000)
Defined Benefit Plan, Plan Assets, Payment for Settlement	10,900,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 335,900,000	$ 301,200,000
Discount rate for the Company Plan	5.10%	5.50%
Net amortization and deferral	$ 0	$ (200,000)	(300,000)
Defined benefit plan costs	200,000	300,000	400,000
Unamortized net gain included in accumulated other comprehensive earnings	(800,000)	(200,000)
Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	99,000,000	53,100,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	99,000,000	53,100,000
Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	236,900,000	248,100,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	236,900,000	248,100,000
Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Benefit Obligation	231,900,000	259,500,000	333,300,000
Service cost	3,900,000	2,800,000	3,900,000
Defined Benefit Plan, Plan Assets, Amount	195,300,000	226,800,000	299,900,000
Employer contributions	0	0
Defined Benefit Plan, Benefit Obligation, Benefits Paid	55,500,000	27,300,000
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)	0	0
Defined Benefit Plan, Interest Cost	12,300,000	9,100,000	8,300,000
Actuarial (gain) loss	11,700,000	(58,400,000)
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	(11,600,000)	(12,900,000)	$ (17,300,000)
Actual return on plan assets	21,600,000	(48,200,000)
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)	$ 0	$ 0
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	5.50%	2.80%	2.40%
Defined-benefit plan costs	$ (20,000,000)	$ (7,700,000)	$ (8,600,000)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 195,300,000	$ 226,800,000	299,900,000
Discount rate for the Company Plan	5.10%	5.50%
Net amortization and deferral	$ (4,500,000)	$ (4,600,000)	(10,000,000)
Defined benefit plan costs	20,000,000	7,700,000	8,600,000
Unamortized net gain included in accumulated other comprehensive earnings	47,200,000	60,900,000
Domestic Plan [Member] | Cash Balance Retirement Plan
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Benefit Obligation, Benefits Paid	53,100,000	24,900,000
Domestic Plan [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	192,000,000	222,900,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	192,000,000	222,900,000
Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Benefit Obligation	345,700,000	319,900,000	569,800,000
Service cost	1,400,000	2,400,000	2,200,000
Defined Benefit Plan, Plan Assets, Amount	335,900,000	301,200,000	485,200,000
Employer contributions	14,100,000	13,800,000
Defined Benefit Plan, Benefit Obligation, Benefits Paid	14,200,000	19,500,000
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)	16,400,000	54,200,000
Defined Benefit Plan, Interest Cost	15,200,000	9,100,000	7,200,000
Actuarial (gain) loss	7,000,000	(187,700,000)
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	(16,700,000)	(15,800,000)	$ (14,300,000)
Actual return on plan assets	18,000,000	(134,700,000)
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)	$ 16,300,000	$ (48,200,000)
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	4%	2.10%	1.10%
Weighted average expected long-term rate of return for other assets (in hundredths)	5.30%	3.60%	3.10%
Defined-benefit plan costs	$ 0	$ 4,600,000	$ 3,000,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 335,900,000	$ 301,200,000	485,200,000
Discount rate for the Company Plan	4.30%	4.80%
Net amortization and deferral	$ (100,000)	$ (800,000)	(1,900,000)
Defined benefit plan costs	0	(4,600,000)	$ (3,000,000)
Unamortized net gain included in accumulated other comprehensive earnings	19,100,000	22,600,000
International - developed [Member] | Domestic Plan [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	11,400,000	17,000,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	11,400,000	17,000,000
Equity Funds | Domestic Plan [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	27,300,000	39,600,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 27,300,000	39,600,000
Real Estate Funds [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	2.10%
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.50%
Real Estate Funds [Member] | Domestic Plan [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 4,000,000	5,000,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 4,000,000	5,000,000
Real Estate Funds [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	3.30%
Real Estate Funds [Member] | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Real Estate Funds [Member] | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	4.30%
Real Estate Funds [Member] | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10%
Life and Annuity Insurance Product Line [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 0
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 0
Life and Annuity Insurance Product Line [Member] | Minimum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Life and Annuity Insurance Product Line [Member] | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10%
Life and Annuity Insurance Product Line [Member] | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Life and Annuity Insurance Product Line [Member] | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	20%
Mutual Funds [Member] | Non-US | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 236,900,000	248,100,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 236,900,000	248,100,000
Equity Securities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	13%
Equity Securities [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	19.80%
Equity Securities [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	26.60%
Equity Securities [Member] | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25%
Equity Securities [Member] | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25.50%
Equity Securities [Member] | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	35%
Fixed Income Securities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	67%
Debt Securities [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	76.40%
Debt Securities [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	40.80%
Debt Securities [Member] | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	35%
Debt Securities [Member] | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	87%
Debt Securities [Member] | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	45%
Other Investments | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	1.70%
Other Investments | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	13.70%
Other Investments | Minimum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Other Investments | Minimum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10%
Other Investments | Maximum [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	5%
Other Investments | Maximum [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25%
U.S. fixed income [Member] | Domestic Plan [Member] | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 149,300,000	161,300,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 149,300,000	$ 161,300,000

PENSION AND POSTRETIREMENT PL_5

PENSION AND POSTRETIREMENT PLANS, OTHER DISCLOSURES (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 335,900,000	$ 301,200,000
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	600,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	500,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	400,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	300,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	300,000
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	1,000,000
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(300,000)	(500,000)
UK Plan
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(13,700,000)	(14,900,000)
Non-US
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	335,900,000	301,200,000	$ 485,200,000
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)	16,400,000	54,200,000
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	16,400,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	16,200,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	17,600,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	18,000,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	18,300,000
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	97,800,000
Funded status	(9,800,000)	22,800,000
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(14,200,000)	(19,500,000)
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	$ 16,700,000	15,800,000	14,300,000
Non-US | Equity Securities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	26.60%
Non-US | Debt Securities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	40.80%
Non-US | Variable Annuity [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	15.70%
Non-US | Real Estate Funds [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	3.30%
Non-US | Other Investments
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	13.70%
Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 195,300,000	226,800,000	299,900,000
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)	0	0
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	21,800,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	22,400,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	21,600,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	20,800,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	21,100,000
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	92,200,000
Funded status	36,600,000	32,700,000
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(55,500,000)	(27,300,000)
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	$ 11,600,000	12,900,000	$ 17,300,000
Domestic Plan [Member] | Equity Securities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	19.80%
Domestic Plan [Member] | Debt Securities [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	76.40%
Domestic Plan [Member] | Variable Annuity [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	0%
Domestic Plan [Member] | Real Estate Funds [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	2.10%
Domestic Plan [Member] | Other Investments
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Actual Asset Allocation	1.70%
Domestic Plan [Member] | Cash Balance Retirement Plan
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Benefit Obligation, Benefits Paid	$ (53,100,000)	(24,900,000)
Accrued Liabilities [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Funded status	700,000	600,000
Accrued Liabilities [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Funded status	2,500,000	2,400,000
Other Liabilities [Member] | Non-US
Defined Benefit Plans Disclosures [Line Items]
Funded status	30,600,000	29,200,000
Other Liabilities [Member] | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Funded status	34,100,000	32,500,000
Other Assets | Non-US
Defined Benefit Plans Disclosures [Line Items]
Funded status	21,500,000	7,000,000
Other Assets | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Funded status	0	2,200,000
Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	236,900,000	248,100,000
Fair Value Measured at Net Asset Value Per Share | Domestic Plan [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	192,000,000	222,900,000
Fair Value Measured at Net Asset Value Per Share | Domestic Plan [Member] | Real Estate Funds [Member]
Defined Benefit Plans Disclosures [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 4,000,000	$ 5,000,000

PENSION AND POSTRETIREMENT PL_6

PENSION AND POSTRETIREMENT PLANS - Funded Status (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Domestic Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	$ (36.6)	$ (32.7)
Non-US
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	9.8	(22.8)
Other Liabilities [Member] | Domestic Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(34.1)	(32.5)
Other Liabilities [Member] | Non-US
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(30.6)	(29.2)
Accrued Liabilities [Member] | Domestic Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(2.5)	(2.4)
Accrued Liabilities [Member] | Non-US
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(0.7)	(0.6)
Other Assets | Domestic Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	0	(2.2)
Other Assets | Non-US
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	$ (21.5)	$ (7)

FAIR VALUE MEASUREMENTS (Detail

FAIR VALUE MEASUREMENTS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Increase (Decrease) in Noncontrolling Interest Put	$ 1,000,000
Long-term debt, less current portion	4,054,700,000	$ 5,038,800,000
Noncontrolling interest puts	15,500,000	15,000,000
Fair market value of senior notes	4,850,400,000	4,973,900,000
Fair Value Hedges, Net	69,600,000	79,700,000
Foreign Currency Contract, Asset, Fair Value Disclosure	109,000,000	45,700,000
Cash Surrender Value, Fair Value Disclosure	95,400,000	100,700,000
Deferred Compensation Plan Assets	21,100,000
Contingent Consideration Classified as Equity, Fair Value Disclosure	66,100,000	77,400,000
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	107,400,000	96,900,000
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Asset		68,300,000
Contingent consideration adjustment	(11,300,000)	(12,800,000)
2018 Swap Agreements | Senior notes due 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Notional Amount	300,000,000
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncontrolling interest puts	0	0
Fair Value Hedges, Net	0	0
Foreign Currency Contract, Asset, Fair Value Disclosure	0	0
Cash Surrender Value, Fair Value Disclosure	0	0
Deferred Compensation Plan Assets	0
Contingent Consideration Classified as Equity, Fair Value Disclosure	0	0
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncontrolling interest puts	15,500,000	15,000,000
Foreign Currency Contract, Asset, Fair Value Disclosure	109,000,000	45,700,000
Interest Rate Fair Value Hedge Asset at Fair Value	69,600,000	79,700,000
Cash Surrender Value, Fair Value Disclosure	95,400,000	100,700,000
Deferred Compensation Plan Assets	21,100,000
Contingent Consideration Classified as Equity, Fair Value Disclosure	0	0
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability		0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncontrolling interest puts	0	0
Fair Value Hedges, Net	0	0
Foreign Currency Contract, Asset, Fair Value Disclosure	0	0
Cash Surrender Value, Fair Value Disclosure	0	0
Deferred Compensation Plan Assets	0
Contingent Consideration Classified as Equity, Fair Value Disclosure	66,100,000	77,400,000	$ 21,900,000
Fair Value Liabilities Measured On Recurring Basis Deferred Compensation Liability	$ 0	$ 0

DERIVATIVE INSTRUMENTS AND HE_3

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Schedule of Derivative Instruments in Statement of Financial Position at Fair Value) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Long-term debt, less current portion	$ 4,054,700,000	$ 4,054,700,000	$ 5,038,800,000
Foreign Currency Contract, Asset, Fair Value Disclosure	109,000,000	109,000,000	45,700,000
2018 Swap Agreements
Derivative [Line Items]
Gain (Loss) on Hedging Activity	900,000
Interest Rate Swap [Member]
Derivative [Line Items]
Fair Value Hedge Assets	0	0	0
Fair Value Hedge Liabilities	(69,600,000)	(69,600,000)	(79,700,000)
Currency Swap [Member]
Derivative [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)		(63,300,000)	(12,900,000)	$ 7,600,000
Fair Value Hedge Assets	0	0	0
Fair Value Hedge Liabilities	(109,000,000)	(109,000,000)	(45,700,000)
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		0	900,000	$ 0
Senior notes due 2020 [Member]
Derivative [Line Items]
Long-term debt, less current portion	500,000,000	500,000,000	500,000,000
Senior notes due 2027 [Member]
Derivative [Line Items]
Long-term debt, less current portion	$ 600,000,000	$ 600,000,000	$ 600,000,000

DERIVATIVE INSTRUMENTS AND HE_4

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Effects of Interest Rate Swap on Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss)
Long-term debt, less current portion	$ 4,054.7	$ 4,054.7	$ 5,038.8
Foreign Currency Contract, Asset, Fair Value Disclosure	$ 109	109	45.7
Three month LIBOR	1.0706%
Senior notes due 2020 [Member]
Derivative Instruments, Gain (Loss)
Long-term debt, less current portion	$ 500	500	500
Senior notes due 2031
Derivative Instruments, Gain (Loss)
Subordinated Borrowing, Interest Rate	2.70%
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss)
Fair Value Hedge Liabilities	$ 69.6	69.6	79.7
Currency Swap [Member]
Derivative Instruments, Gain (Loss)
Fair Value Hedge Liabilities	$ 109	109	45.7
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)		(63.3)	(12.9)	$ 7.6
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		$ 0	$ 0.9	$ 0

SUPPLEMENTAL CASH FLOW INFORM_3

SUPPLEMENTAL CASH FLOW INFORMATION (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash paid during period for:
Interest	$ 221,500,000	$ 196,700,000	$ 194,500,000
Income taxes, net of refunds	206,800,000	474,900,000	964,700,000
Disclosure of non-cash financing and investing activities
Change in accrued property, plant and equipment	$ 13,200,000		$ 11,300,000
Decrease in capital expenditures incurred but not paid		$ (5,600,000)

BUSINESS SEGMENT INFORMATION (D

BUSINESS SEGMENT INFORMATION (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 2,911.8	$ 2,794.1
Depreciation and amortization:
Depreciation and amortization	357.5	343.6	$ 347.5
Revenues	12,161.6	11,863.9	13,136.1
Operating Income (Loss)	725.6	1,436.5	3,048.6
Amortization of intangibles and other assets	(219.8)	(193.6)	(229.5)
Net restructuring charges	(49.1)	(54)	(24)
Goodwill and Intangible Asset Impairment	(349)	(261.7)	0
Provision for income taxes	188.5	233.9	690
Net earnings	419.2	1,280.6	2,379.5
Net Income (Loss) Attributable to Noncontrolling Interest	(1.2)	(1.5)	(2.2)
Net earnings attributable to Laboratory Corporation of America Holdings	418	1,279.1	2,377.3
Operating Segments
Depreciation and amortization:
Operating Income (Loss)	1,987.6	2,414.6	3,706.6
Intersegment Eliminations
Depreciation and amortization:
Revenues	27.7	36.9	88.2
LabCorp Diagnostics [Member] | Operating Segments
Segment Reporting Information [Line Items]
Property, plant and equipment, net	1,799.2	1,669.2
Depreciation and amortization:
Depreciation and amortization	236.1	227.1	238.6
Revenues	9,415.1	9,203.5	10,363.6
Operating Income (Loss)	1,591.3	2,025.5	3,205.6
Covance Drug Development [Member]
Depreciation and amortization:
Goodwill and Intangible Asset Impairment	(333.6)
Covance Drug Development [Member] | Operating Segments
Segment Reporting Information [Line Items]
Property, plant and equipment, net	1,112.6	1,124.9
Depreciation and amortization:
Depreciation and amortization	112.5	112.8	106.3
Revenues	2,774.2	2,697.3	2,860.7
Operating Income (Loss)	396.3	389.1	501
Corporate Segment [Member]
Depreciation and amortization:
Depreciation and amortization	8.9	3.7	2.6
Operating Income (Loss)	(644.1)	(468.8)	$ (404.5)
Other countries [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	98.9	102.7
Other countries [Member] | LabCorp Diagnostics [Member] | Operating Segments
Segment Reporting Information [Line Items]
Property, plant and equipment, net	0	0
Other countries [Member] | Covance Drug Development [Member] | Operating Segments
Segment Reporting Information [Line Items]
Property, plant and equipment, net	98.9	102.7
North America
Segment Reporting Information [Line Items]
Property, plant and equipment, net	2,418.2	2,308.9
North America | LabCorp Diagnostics [Member] | Operating Segments
Segment Reporting Information [Line Items]
Property, plant and equipment, net	1,799.2	1,669.2
North America | Covance Drug Development [Member] | Operating Segments
Segment Reporting Information [Line Items]
Property, plant and equipment, net	619	639.7
Europe [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	394.7	382.4
Europe [Member] | LabCorp Diagnostics [Member] | Operating Segments
Segment Reporting Information [Line Items]
Property, plant and equipment, net	0	0
Europe [Member] | Covance Drug Development [Member] | Operating Segments
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 394.7	$ 382.4

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event - $ / shares	Mar. 13, 2024	Feb. 27, 2024	Feb. 14, 2024	Jan. 12, 2024
Subsequent Event [Line Items]
Dividends Payable, Date to be Paid	Mar. 13, 2024
Dividends Payable, Date Declared				Jan. 12, 2024
Dividends Payable, Date of Record		Feb. 27, 2024
Dividends Payable, Amount Per Share				$ 720,000
Subsequent Event, Description			300.0

Uncategorized Items - lh-202312

Label	Element	Value
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	$ 1,320,800,000