Financial Instruments and Risk Management (Effect of Derivative Instruments on the Condensed Consolidated Statements of Comprehensive Earnings Derivatives in Net Investment Hedging Relationship) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Gains and Losses on Derivatives in Cash Flow Hedging Relationships | Foreign currency borrowings and forward contracts | Net Investment Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	$ (238.4)	$ (1.4)	$ 0.0