Accumulated Other Comprehensive (Loss) Income, Accumulated Other Comprehensive (Loss) Income Balances (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018		Sep. 30, 2017
Before-Tax Amount [Abstract]
Foreign currency translation adjustments, net	$ (21.9)	$ 41.5	$ (70.0)		$ 131.4
Foreign currency gains (losses), net	4.7	(23.5)	24.4		(71.2)
Unrecognized (losses) gains on cash flow hedges, net	5.8	5.5	27.1		8.9
Pension and other postretirement benefit prior service cost and gain or loss, net	1.0	(1.1)	3.0		(3.4)
Other comprehensive (loss) income	(10.4)	22.4	(15.5)		65.7
Tax (Expense) or Benefit [Abstract]
Foreign currency translation adjustments, net	0.0	0.0	0.0		0.0
Foreign currency gains (losses), net	(1.1)	8.7	(5.7)		26.9
Unrecognized (losses) gains on cash flow hedges, net	(1.4)	(1.5)	(6.6)		(3.4)
Pension and other postretirement benefit prior service cost and gain or loss, net	(0.1)	0.5	0.9		1.5
Other comprehensive (loss) income	(2.6)	7.7	(11.4)		25.0
Net of Tax Amount [Abstract]
Foreign currency translation adjustments, net	(21.9)	41.5	(70.0)		131.4
Foreign currency gains (losses), net	3.6	(14.8)	18.7		(44.3)
Unrecognized (losses) gains on cash flow hedges, net	4.4	4.0	20.5		5.5
Pension and other postretirement benefit prior service cost and gain or loss, net	0.9	(0.6)	3.9		(1.9)
Total other comprehensive (loss) income, net of tax	$ (13.0)	$ 30.1	$ (26.9)	[1]	$ 90.7	[1]

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