Accumulated Other Comprehensive (Loss) Income, Accumulated Other Comprehensive (Loss) Income Balances (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Before-Tax Amount [Abstract]
Foreign currency translation adjustments, net		$ 51.4	$ 25.7
Foreign currency gains (losses), net		(21.7)	(6.2)
Unrecognized (losses) gains on cash flow hedges, net		15.1	4.9
Pension and other postretirement benefit prior service cost and gain or loss, net		(1.2)	(0.1)
Other comprehensive (loss) income		43.6	24.3
Tax (Expense) or Benefit [Abstract]
Foreign currency translation adjustments, net		0.0	0.0
Foreign currency gains (losses), net		4.7	2.3
Unrecognized (losses) gains on cash flow hedges, net		(3.7)	(1.9)
Pension and other postretirement benefit prior service cost and gain or loss, net		1.6	0.3
Other comprehensive (loss) income		2.6	0.7
Net of Tax Amount [Abstract]
Foreign currency translation adjustments, net		51.4	25.7
Foreign currency gains (losses), net		(17.0)	(3.9)
Unrecognized (losses) gains on cash flow hedges, net		11.4	3.0
Pension and other postretirement benefit prior service cost and gain or loss, net		0.4	0.2
Total other comprehensive income, net of tax	[1]	$ 46.2	$ 25.0

[1] All amounts are net of tax. Amounts in parentheses indicate debits.