Financial Instruments and Risk Management (Effect of Derivative Instruments on the Consolidated Statements of Operations Derivatives Not Designated as Hedging Instruments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Hedging Items			$ 15.0
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	$ (104.5)	$ (29.5)	(78.3)
Interest rate swaps | Other expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	0.0	(71.2)	0.0
Foreign currency forward contracts | Other income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives		41.7
Foreign currency forward contracts | Other expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	(104.5)		(78.3)
Cash conversion feature of Cash Convertible Notes | Other income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	0.0	1,853.5
Cash conversion feature of Cash Convertible Notes | Other expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives			(550.2)
Purchased cash convertible note hedge | Other income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives			550.2
Purchased cash convertible note hedge | Other expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	0.0	(1,853.5)
Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Hedging Items	10.0	(5.9)	(27.0)
Fair Value Hedging [Member] | 2018 Senior Notes (6.000% coupon) | Other expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Hedging Items	$ 0.0	$ 0.0	$ 15.0