BUSINESS ACQUISITIONS (Details) - USD ($) $ in Millions		3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 03, 2019	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Business Combination Purchase Price Allocation [Line Items]
Revenues		$ 2,768.8		$ 2,881.7		$ 5,592.6	$ 5,672.9
Operating Income (Loss)		297.7		335.7		105.1	653.9
Net Income (Loss) Attributable to Parent		231.6	$ (317.2)	190.4	$ 185.6	(85.6)	376.0
Goodwill		7,422.7				7,422.7		$ 7,865.0
Cash payments for laboratory-related assets						205.1	179.4
Payments to Acquire Businesses, Net of Cash Acquired						11.3	703.7
Notes Receivable, Fair Value Disclosure	$ 110.0	0.0		110.0		0.0	110.0
Total acquisition consideration (cash, stock, notes, etc.)	711.0
Gain (Loss) on Disposition of Assets								(12.2)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net		0.0				0.0
Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	(15.1)	$ (11.3)				(11.3)
Payments to Acquire Businesses, Net of Cash Acquired	601.0
Notes Receivable, Fair Value Disclosure	110.0
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		11 years
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	(16.5)	$ (12.1)				(12.1)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other	(26.5)	(25.6)				(25.6)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	4.5	4.5				4.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	3.5	10.8				10.8
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	(25.5)	(25.2)				(25.2)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	99.1	128.4				128.4
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	(432.2)	(376.6)				(376.6)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	125.8	141.4				141.4
Indefinite-Lived Trade Names	0.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets	9.9	9.9				9.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	(759.2)	(745.8)				(745.8)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	(15.4)	(15.2)				(15.2)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	(11.6)	(10.4)				(10.4)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue	49.9	49.9				49.9
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation	(15.0)	0.0				0.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities	66.3	69.3				69.3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(158.2)	(144.8)				(144.8)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	$ 601.0	601.0				601.0
Trade Names [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		0.6				0.6
Customer Relationships [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets		140.8				140.8
Trademarks and Trade Names [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Indefinite-Lived Trade Names		0.0				0.0
Cash and Cash Equivalents [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents		(3.8)				(3.8)
Accounts Receivable [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables		(4.4)				(4.4)
Other Current Assets [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other		(0.9)				(0.9)
Inventories [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory		0.0				0.0
Prepaid Expenses and Other Current Assets [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets		7.3				7.3
Property, Plant and Equipment [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		29.3				29.3
Deferred Tax Asset [Domain] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets		(0.3)				(0.3)
Goodwill [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		(55.6)				(55.6)
Customer Relationships [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		15.0				15.0
Other Noncurrent Assets [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets		0.0				0.0
Assets [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		(13.4)				(13.4)
Accounts Payable [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable		(0.2)				(0.2)
Accrued Liabilities [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other		(1.2)				(1.2)
Deferred Revenue [Domain] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		0.0				0.0
Other Liabilities [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation		(15.0)				(15.0)
Other Noncurrent Liabilities [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities		3.0				3.0
Liability [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		(13.4)				(13.4)
Covance Drug Development [Member]
Business Combination Purchase Price Allocation [Line Items]
Revenues		1,093.7		1,126.3		2,237.5	2,201.0
Operating Income (Loss)		65.5		$ 65.8		(273.2)	$ 153.8
Goodwill		$ 3,690.4				3,690.4		$ 4,143.5
Covance Drug Development [Member] | Envigo [Member]
Business Combination Purchase Price Allocation [Line Items]
impairment of floating rate note receivable						$ 5.0