Condensed Consolidated Statements Of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract]
Foreign currency translation adjustments, tax (expense) benefit	$ (0.9)	$ 0.0	$ (4.8)	$ 0.0
Net unrealized gains (losses) on available-for-sale securities, tax (expense) benefit	0.0	0.0	0.0	0.0
Net gains (losses) on hedging instruments, tax (expense) benefit	(12.1)	(4.8)	(49.4)	(25.7)
Net pensions and other post-retirement benefits, tax (expense) benefit	$ 0.7	$ 0.2	$ 1.1	$ 0.4