Accumulated Other Comprehensive (Loss) Income, Changes in Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018		Dec. 31, 2017
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive (loss) income before reclassifications	[1]	$ (1.2)	$ 42.2
Amounts reclassified from accumulated other comprehensive (loss) income	[1]	3.2	4.0
Total other comprehensive income, net of tax	[1]	2.0	46.2
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[1]	(247.0)	(199.8)
Balance at end of period	[1]	(253.2)	(153.3)
Accumulated Other Comprehensive Income (Loss) [Member] | ASU 2018-02 [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative effect adjustment upon adoption of new accounting standard				$ (8.2)	[1]	$ 0.0
Accumulated Other Comprehensive Income (Loss) [Member] | ASU 2017-12 [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative effect adjustment upon adoption of new accounting standard				0.0		0.3	[1]
Foreign Currency Translation Adjustments, Net [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[1]	(190.6)	(129.6)
Other comprehensive (loss) income before reclassifications	[1]	(0.1)	34.4
Amounts reclassified from accumulated other comprehensive (loss) income	[1]	0.0	0.0
Total other comprehensive income, net of tax	[1]	(0.1)	34.4
Balance at end of period	[1]	(192.2)	(95.2)
Foreign Currency Translation Adjustments, Net [Member] | ASU 2018-02 [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative effect adjustment upon adoption of new accounting standard	[1]			(1.5)
Foreign Currency Translation Adjustments, Net [Member] | ASU 2017-12 [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative effect adjustment upon adoption of new accounting standard	[1]					0.0
Unrealized (Losses) Gains on Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[1]	(11.4)	(29.8)
Other comprehensive (loss) income before reclassifications	[1]	(0.9)	7.8
Amounts reclassified from accumulated other comprehensive (loss) income	[1]	2.8	3.6
Total other comprehensive income, net of tax	[1]	1.9	11.4
Balance at end of period	[1]	(16.2)	(18.1)
Unrealized (Losses) Gains on Cash Flow Hedges [Member] | ASU 2018-02 [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative effect adjustment upon adoption of new accounting standard	[1]			(6.7)
Unrealized (Losses) Gains on Cash Flow Hedges [Member] | ASU 2017-12 [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative effect adjustment upon adoption of new accounting standard	[1]					0.3
Pension and Postretirement Benefit Plans [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[1]	(45.0)	(40.4)
Other comprehensive (loss) income before reclassifications	[1]	(0.2)	0.0
Amounts reclassified from accumulated other comprehensive (loss) income	[1]	0.4	0.4
Total other comprehensive income, net of tax	[1]	0.2	0.4
Balance at end of period	[1]	$ (44.8)	$ (40.0)
Pension and Postretirement Benefit Plans [Member] | ASU 2018-02 [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative effect adjustment upon adoption of new accounting standard	[1]			$ 0.0
Pension and Postretirement Benefit Plans [Member] | ASU 2017-12 [Member]
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative effect adjustment upon adoption of new accounting standard	[1]					$ 0.0

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