Financial Instruments and Risk Management (Narrative) (Details) € in Millions, $ in Millions		3 Months Ended	12 Months Ended
		Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)		Dec. 31, 2016 USD ($)		May 23, 2018	Apr. 09, 2018	Nov. 22, 2016	Aug. 05, 2016 EUR (€)	Jun. 15, 2016 USD ($)	Jun. 09, 2016 USD ($)	Sep. 17, 2015 USD ($)	Dec. 24, 2013 USD ($)
Derivative [Line Items]
Notional amount of derivative		$ 750.0		$ 750.0
Maximum length of time hedged in cash flow hedge, in years			10 years
Debt instrument, interest rate at period end			2.86%
Pre-tax net losses on cash flow hedges to be reclassified from AOCE into earnings in next twelve months			$ (58.0)
Purchase consideration, contingent consideration		453.7	355.3	453.7		$ 564.6
Reclassifications			0.0	0.0
Accretion			19.8	25.9
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net			34.8	47.7		(104.5)
Contingent consideration payments			(82.9)	(77.5)	[1]
Fair value loss (gain)	[1]		(35.3)	(59.3)
Minimum
Derivative [Line Items]
Accretion			15.0
Maximum
Derivative [Line Items]
Accretion			20.0
Jai Pharma Limited
Derivative [Line Items]
Fair value loss (gain)			(8.6)	(9.9)
Respiratory delivery platform [Member]
Derivative [Line Items]
Purchase consideration, contingent consideration			336.5
Fair value loss (gain)			44.0	93.5
Topicals Business
Derivative [Line Items]
Purchase consideration, contingent consideration												$ 16.0
Acquisitions				23.5
Contingent consideration payments		40.0
Senior Notes | 2020 Floating Rate Euro Notes [Domain]
Derivative [Line Items]
Long-term debt		600.2	573.3	600.2
Senior Notes | 2026 Senior Notes (3.950%)
Derivative [Line Items]
Long-term debt		2,235.0	2,236.5	2,235.0									$ 2,250.0
Debt instrument, interest rate, stated percentage													3.95%
Senior Notes | 2020 Euro Senior Notes
Derivative [Line Items]
Long-term debt		897.6	858.1	897.6
Debt instrument, interest rate, stated percentage										1.25%
Senior Notes | 2024 Euro Senior Notes
Derivative [Line Items]
Long-term debt		1,197.7	1,144.2	1,197.7
Debt instrument, interest rate, stated percentage										2.25%
Senior Notes | 2023 Senior Notes (3.125% coupon)
Derivative [Line Items]
Notional amount of derivative			750.0
Long-term debt		765.4	752.9	765.4
Debt instrument, interest rate, stated percentage															3.125%
Aggregate principal amount															$ 750.0
Senior Notes | 2028 Senior Notes [Member]
Derivative [Line Items]
Long-term debt		0.0	748.2	0.0
Debt instrument, interest rate, stated percentage									4.55%
Senior Notes | 2025 Euro Senior Notes [Member]
Derivative [Line Items]
Long-term debt		0.0	572.0	0.0
Debt instrument, interest rate, stated percentage								2.125%
Net Investment Hedging
Derivative [Line Items]
Notional amount of derivative		1,854.0	2,354.0	1,854.0
Long-term debt			3,500.0
Net Investment Hedging | 2020 Floating Rate Euro Notes [Domain]
Derivative [Line Items]
Notional amount of derivative		0.0	0.0	0.0
Long-term debt			500.0
Net Investment Hedging | 2020 Euro Senior Notes
Derivative [Line Items]
Notional amount of derivative		104.0	104.0	104.0
Long-term debt			750.0
Net Investment Hedging | 2024 Euro Senior Notes
Derivative [Line Items]
Notional amount of derivative		1,000.0	1,000.0	1,000.0
Long-term debt			1,000.0
Net Investment Hedging | 2028 Senior Notes [Member]
Derivative [Line Items]
Notional amount of derivative		750.0	750.0	750.0
Long-term debt			750.0
Net Investment Hedging | 2025 Euro Senior Notes [Member]
Derivative [Line Items]
Notional amount of derivative		0.0	500.0	0.0
Long-term debt			500.0
Interest rate swaps
Derivative [Line Items]
Notional amount of derivative | €											€ 750
September 2015 Swaps Effective Date June 2016
Derivative [Line Items]
Notional amount of derivative														$ 500.0
September 2015 Swaps Effective Date November 2016
Derivative [Line Items]
Notional amount of derivative														$ 500.0
Other Comprehensive Income (Loss) | September 2015 Swaps Effective Date June 2016
Derivative [Line Items]
Derivative, Loss on Derivative			64.9
Other Noncurrent Liabilities
Derivative [Line Items]
Purchase consideration, contingent consideration		285.9	197.0	285.9		307.7	[2]
Reclassifications	[2]		(62.1)	(27.0)
Accretion	[2]		19.8	25.9
Contingent consideration payments	[2]		0.0	(0.2)	[1]
Fair value loss (gain)	[1],[2]		(46.6)	(20.5)
Other current liabilities
Derivative [Line Items]
Purchase consideration, contingent consideration		$ 167.8	158.3	167.8		$ 256.9	[3]
Reclassifications	[3]		62.1	27.0
Accretion	[3]		0.0	0.0
Contingent consideration payments	[3]		(82.9)	(77.3)	[1]
Fair value loss (gain)	[1],[3]		11.3	(38.8)
Other current liabilities | Agila Specialties
Derivative [Line Items]
Contingent consideration payments			51.0	13.7
Other current liabilities | Jai Pharma Limited
Derivative [Line Items]
Contingent consideration payments			$ 30.0	20.0
Other current liabilities | Topicals Business
Derivative [Line Items]
Contingent consideration payments				$ 40.0
Measurement Input, Discount Rate [Member] | Minimum
Derivative [Line Items]
Derivative Asset (Liability) Net, Measurement Input		0.005		0.005
Measurement Input, Discount Rate [Member] | Maximum
Derivative [Line Items]
Derivative Asset (Liability) Net, Measurement Input		0.100		0.100
Measurement Input, Discount Rate [Member] | Contingent consideration | Minimum
Derivative [Line Items]
Rate used to discount net cash inflows to present values			0.021
Measurement Input, Discount Rate [Member] | Contingent consideration | Maximum
Derivative [Line Items]
Rate used to discount net cash inflows to present values			0.110

[1] Included in litigation settlements and other contingencies, net in the Consolidated Statements of Operations.

[2] Included in other long-term obligations on the Consolidated Balance Sheets.

[3] Included in other current liabilities on the Consolidated Balance Sheets.