DEBT - COVERTIBLE SUBORDINATED NOTES (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2017 USD ($) shares	Mar. 31, 2016 shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($)	Sep. 30, 2017 USD ($) Rate	Sep. 30, 2016 USD ($)	Jan. 30, 2015 USD ($)	Nov. 01, 2013 USD ($)
Debt Instrument [Line Items]
2017 Term loan			$ 527,100,000	$ 750,000,000
Notes Payable, Noncurrent			7,100,000	8,900,000
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months			10,000,000
Convertible Subordinated Debt, Current			8,700,000	8,800,000
Short term debt issuance costs			(500,000)	(1,400,000)
Capital Lease Obligations, Current			7,900,000	8,300,000
Notes Payable, Current			1,800,000	1,800,000
Long-term debt, less current portion			6,041,900,000	6,344,600,000
Senior notes due 2024			600,000,000	600,000,000
Senior Notes, Noncurrent			2,900,000,000						$ 700,000,000
Foreign Currency Contract, Asset, Fair Value Disclosure			(2,800,000)
Debt, Current			17,900,000	417,500,000
Payments On Zero Coupon Subordinated Notes			$ 300,000	$ 25,200,000	$ 40,300,000
Common stock issued upon conversion of zero-coupon subordinated notes (in shares) | shares	300,000	400,000	0
Cross currency swap maturing 2025 [Member]
Debt Instrument [Line Items]
Derivative, Notional Amount			$ 300,000,000
Senior notes due 2045 [Member]
Debt Instrument [Line Items]
Senior Notes, Noncurrent								$ 900,000,000
Senior notes due 2024 and 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion						$ 1,200,000,000
Net Proceeds from Debt						1,190,100,000
Senior notes due 2024 [Member] [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion						$ 600,000,000
Debt Instrument, Interest Rate, Effective Percentage | Rate						3.25%
Senior notes due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion			600,000,000			$ 600,000,000
Debt Instrument, Interest Rate, Effective Percentage | Rate						3.60%
Cross currency swap maturing 2022 [Member]
Debt Instrument [Line Items]
Derivative, Notional Amount			300,000,000
Senior notes due 2022 [Member]
Debt Instrument [Line Items]
Senior Notes, Noncurrent								500,000,000
Foreign Currency Contract, Asset, Fair Value Disclosure			(1,000,000)
Senior notes due 2025 [Member] [Member]
Debt Instrument [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure			(1,800,000)
Senior notes due 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage | Rate						2.20%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt to EBITDA (leverage) ratio				3,000,000
Senior notes due 2018 [Member]
Debt Instrument [Line Items]
Senior notes due 2018			0	$ 400,000,000
Long-term debt, less current portion							$ 130,000,000
Zero-coupon convertible subordinated notes [Member]
Debt Instrument [Line Items]
Principal amount at maturity of zero-coupon subordinated notes outstanding			8,600,000	9,000,000
Issued price per principal amount at maturity			$ 671.65
Principal amount of zero-coupon subordinated notes				$ 1,000.0
Debt Instrument, Interest Rate, Effective Percentage				2.00%
Stock conversion rate for zero-coupon subordinated notes (per thousand) | shares				13.4108
Minimum number of trading days in a period the common stock sale price must meet a specified threshold to trigger conversion price (in days)	20
Number of consecutive trading days ending on the last trading day of the preceding quarter for the common stock sale price to reach a specified threshold to trigger conversion price (in days)	30
Common stock sales price threshold, beginning	120.00%
Common stock sales price threshold, declining per quarter	0.1282%
Common stock sales price threshold, ending	110.00%
Zero Coupon Convertible Subordinated Notes Conversion Trigger Price | $ / shares			$ 78.64
Principal Amount At Maturity Of Zero Coupon Subordinated Notes Converted	$ 37,100,000		$ 300,000
Value Of Cash And Common Stock In Connection With Conversions Of Zero Coupon Subordinated Notes Settled In Current Period	33,900,000		700,000
Payments On Zero Coupon Subordinated Notes	$ 33,900,000		$ 300,000
Common stock issued upon conversion of zero-coupon subordinated notes (in shares) | shares	300,000		0
Tax Benefit Realized Upon Conversion Of Zero Coupon Convertible Debt	$ 13,700,000		$ 200,000
Contingent cash interest accrual rate description	no less than 0.125% of the average market price of a zero-coupon subordinated note for the five trading days ended September 8, 2018, in addition to the continued accrual of the original issue discount
Contingent cash interest accrual rate	0.125%
Number of days used to establish average market price of zero coupon subordinated notes	5
Debt Conversion Date Of Subordinated Notes And Indenture			Oct. 24, 2006
Covance [Member]
Debt Instrument [Line Items]
Net Proceeds from Debt								$ 2,870,200,000