Accumulated Other Comprehensive (Loss) Income, Accumulated Other Comprehensive (Loss) Income Balances (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017		Sep. 30, 2016
Before-Tax Amount [Abstract]
Foreign currency translation adjustments, net	$ 41.5	$ (29.4)	$ 131.4		$ 12.8
Foreign currency (losses) gains, net	(23.5)	11.2	(71.2)		(18.2)
Unrecognized (losses) gains on cash flow hedges, net	5.5	(4.5)	8.9		(21.7)
Pension and other postretirement benefit prior service cost and gain or loss, net	(1.1)	6.2	(3.4)		7.5
Other comprehensive income (loss)	22.4	(16.5)	65.7		(19.6)
Tax (Expense) or Benefit [Abstract]
Foreign currency translation adjustments, net	0.0	0.0	0.0		0.0
Foreign currency (losses) gains, net	8.7	(3.1)	26.9		7.4
Unrecognized (losses) gains on cash flow hedges, net	(1.5)	1.7	(3.4)		8.2
Pension and other postretirement benefit prior service cost and gain or loss, net	0.5	(1.0)	1.5		(1.2)
Other comprehensive income (loss)	7.7	(2.4)	25.0		14.4
Net of Tax Amount [Abstract]
Foreign currency translation adjustments, net	41.5	(29.4)	131.4		12.8
Foreign currency (losses) gains, net	(14.8)	8.1	(44.3)		(10.8)
Unrecognized (losses) gains on cash flow hedges, net	4.0	(2.8)	5.5		(13.5)
Pension and other postretirement benefit prior service cost and gain or loss, net	(0.6)	5.2	(1.9)		6.3
Total other comprehensive income (loss), net of tax	$ 30.1	$ (18.9)	$ 90.7	[1]	$ (5.2)	[1]

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