Accumulated Other Comprehensive Income (Loss) - Changes in Each Component of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance			$ 520.7
Total other comprehensive (loss) income, net of tax	$ (49.8)	$ 19.0	(18.8)	$ 37.8
Balance	532.5		532.5
Accumulated Other Comprehensive Income (Loss) [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance	(54.4)	(139.1)	(85.4)	(157.9)
Other comprehensive (loss) income before reclassifications	(49.8)	18.5	(18.9)	37.1
Amounts reclassified from accumulated other comprehensive income (loss)	0.0	0.5	0.1	0.7
Total other comprehensive (loss) income, net of tax	(49.8)	19.0	(18.8)	37.8
Balance	(104.2)	(120.1)	(104.2)	(120.1)
Foreign Currency Translation [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance	(51.7)	(131.2)	(78.3)	(150.0)
Other comprehensive (loss) income before reclassifications	(51.6)	20.9	(25.0)	39.7
Amounts reclassified from accumulated other comprehensive income (loss)	0.0	0.0	0.0	0.0
Total other comprehensive (loss) income, net of tax	(51.6)	20.9	(25.0)	39.7
Balance	(103.3)	(110.3)	(103.3)	(110.3)
Unrecognized Post- Retirement Plan Losses [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance	(7.2)	(7.4)	(7.2)	(7.3)
Other comprehensive (loss) income before reclassifications	0.3	(0.3)	0.2	(0.6)
Amounts reclassified from accumulated other comprehensive income (loss)	0.2	0.1	0.3	0.3
Total other comprehensive (loss) income, net of tax	0.5	(0.2)	0.5	(0.3)
Balance	(6.7)	(7.6)	(6.7)	(7.6)
Derivative Financial Instruments [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance	4.5	(0.5)	0.1	(0.6)
Other comprehensive (loss) income before reclassifications	1.5	(2.1)	5.9	(2.0)
Amounts reclassified from accumulated other comprehensive income (loss)	(0.2)	0.4	(0.2)	0.4
Total other comprehensive (loss) income, net of tax	1.3	(1.7)	5.7	(1.6)
Balance	$ 5.8	$ (2.2)	$ 5.8	$ (2.2)