BUSINESS ACQUISITIONS (Details) € in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($) Rate	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) Rate	Sep. 30, 2024 EUR (€)	Sep. 30, 2023 USD ($)
Business Combinations [Abstract]
Payments to Acquire Businesses, Net of Cash Acquired			$ 751,200,000		$ 516,700,000
Business Acquisition [Line Items]
Goodwill, Acquired During Period			349,500,000		230,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	$ (847,000,000.0)	$ (520,600,000)	(847,000,000.0)		(520,600,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities		0			0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(65,800,000)	(3,900,000)	(65,800,000)		(3,900,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	781,200,000	516,700,000	781,200,000		516,700,000
Business Acquisition, Pro Forma Revenue	3,333,800,000	3,152,700,000	9,999,900,000		9,354,400,000
Business Acquisition, Pro Forma Net Income (Loss)	172,200,000	174,800,000	613,100,000		582,700,000
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	90,000,000.0	4,700,000	90,000,000.0		4,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	13,900,000	1,300,000	13,900,000		1,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	(401,000,000.0)	(284,600,000)	(401,000,000.0)		(284,600,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents		0			0
Payments to Acquire Businesses, Net of Cash Acquired			751,200,000		516,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	393,600,000		393,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0		0
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	751,200,000		751,200,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory			0		0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment			(3,900,000)
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments Related to Previous Period			0		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue	3,300,000		3,300,000
Escrow Deposit	30,000,000.0		30,000,000.0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles			7,400,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets		2,100,000			2,100,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Assets			(3,900,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities		3,900,000			3,900,000
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation	62,500,000		62,500,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables		(3,000,000.0)			(3,000,000.0)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets		400,000			400,000
Estimated amortization expense, 2012	$ 71,000,000.0		71,000,000.0
Gain (Loss) on Disposition of Business			(4,900,000)
Goodwill acquired during the period net of measurement period adjustments			342,100,000
Payments to Acquire Equity Method Investments			42,300,000		20,100,000
Proceeds from Sales of Business, Affiliate and Productive Assets			$ 13,500,000		0
SYNLAB
Business Acquisition [Line Items]
Subsidiary, Ownership Percentage, Noncontrolling Owner | Rate	15.00%		15.00%
Accrued Liabilities [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments Related to Previous Period					(8,300,000)
Other Noncurrent Liabilities [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments Related to Previous Period					(2,300,000)
Prepaid Expenses and Other Current Assets [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments Related to Previous Period					600,000
Other Noncurrent Assets [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments Related to Previous Period					0
Goodwill [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles					(29,400,000)
Other acquirees
Business Combinations [Abstract]
Finite-lived Intangible Assets Acquired					284,600,000
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired					284,600,000
Goodwill, Acquired During Period					230,500,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment					(1,500,000)
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles					19,500,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Assets					(10,600,000)
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities					(10,600,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents					200,000
Providence Medical Foundation
Business Acquisition [Line Items]
Goodwill, Acquired During Period			$ 25,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	$ (55,800,000)		(55,800,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	(900,000)		(900,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(900,000)		(900,000)
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	900,000		900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	29,000,000.0		29,000,000.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0		0
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	54,900,000		54,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue	0		0
Escrow Deposit	0		0
Westpac Labs, Inc.
Business Acquisition [Line Items]
Goodwill, Acquired During Period			45,100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(97,700,000)		(97,700,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	0		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	0		0
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	0		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	1,800,000		1,800,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	50,800,000		50,800,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0		0
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	97,700,000		97,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue	0		0
Escrow Deposit	0		0
Baystate Medical Center
Business Acquisition [Line Items]
Goodwill, Acquired During Period			70,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(157,400,000)		(157,400,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	(7,200,000)		(7,200,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(7,200,000)		(7,200,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	150,200,000		150,200,000
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	7,200,000		7,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	79,500,000		79,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	120,200,000		120,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue	0		0
Escrow Deposit	30,000,000.0		30,000,000.0
Other Acquisitions
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		28,900,000			28,900,000
Escrow Deposit	0		0
Invitae Corporation
Business Acquisition [Line Items]
Goodwill, Acquired During Period			100,400,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(302,400,000)		(302,400,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	(58,300,000)		(58,300,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(61,600,000)		(61,600,000)
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	76,700,000		76,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	12,100,000		12,100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	113,200,000		113,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0		0
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	240,800,000		240,800,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue	3,300,000		3,300,000
Escrow Deposit	0		0
BioReference Health
Business Acquisition [Line Items]
Goodwill, Acquired During Period			107,400,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(237,600,000)		(237,600,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	0		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	0		0
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	9,100,000		9,100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	0		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	121,100,000		121,100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	0		0
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	237,600,000		237,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue	0		0
Escrow Deposit	0		0
Tufts
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		157,000,000.0			157,000,000.0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments Related to Previous Period			(7,400,000)
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities	(3,900,000)		(3,900,000)
2024 Measurement Period Adjustments
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue	$ 0		0
SYNLAB | United States of America, Dollars
Business Acquisition [Line Items]
Payments to Acquire Equity Method Investments			$ 155,900,000
SYNLAB | Euro Member Countries, Euro
Business Acquisition [Line Items]
Payments to Acquire Equity Method Investments | €				€ 140.0
Jefferson Health
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		108,000,000.0			108,000,000.0
Enzo BioChem
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		112,800,000			112,800,000
Providence Health and Services Oregon
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		110,000,000.0			110,000,000.0
Total business acquisitions and adjustments
Business Acquisition [Line Items]
Goodwill, Acquired During Period					201,100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		(510,000,000.0)			(510,000,000.0)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities		2,300,000			2,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		6,700,000			6,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net		516,700,000			516,700,000
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets		3,200,000			3,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory		1,300,000			1,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		(304,100,000)			(304,100,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents		200,000			200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets		2,100,000			2,100,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities		(4,400,000)			(4,400,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables		3,000,000.0			3,000,000.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets		$ 1,000,000.0			$ 1,000,000.0
Customer Lists | Maximum [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			15 years	15 years	15 years
Customer Lists | Minimum [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			5 years	5 years	5 years