Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 1,869.9
Other comprehensive income (loss) before reclassifications	254.1	$ (14.4)	$ (60.4)
Amounts reclassified from accumulated other comprehensive income (loss)	16.1	13.6	12.9
Other comprehensive income (loss), net of tax	270.2	(0.8)	(47.5)
Stockholders' equity	9,189.5	1,869.9	1,676.0	$ 1,476.8
Ending balance	9,119.7	1,869.9
Cumulative Effect, Period of Adoption, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		(8.2)	0.3
Stockholders' equity		(1.0)	0.0	0.0
Ending balance			(8.2)
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(256.0)	(247.0)	(199.8)
Stockholders' equity	14.2	(256.0)	(247.0)	(199.8)
Ending balance	14.2	(256.0)	(247.0)
Accumulated Other Comprehensive Income (Loss) | Cumulative Effect, Period of Adoption, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Stockholders' equity			(8.2)	0.3
Foreign Currency Translation Adjustments, Net
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(193.6)	(190.6)	(129.6)
Other comprehensive income (loss) before reclassifications	268.2	(1.5)	(61.0)
Amounts reclassified from accumulated other comprehensive income (loss)	0.0	0.0	0.0
Other comprehensive income (loss), net of tax	268.2	(1.5)	(61.0)
Ending balance	74.6	(193.6)	(190.6)
Foreign Currency Translation Adjustments, Net | Cumulative Effect, Period of Adoption, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		(1.5)	0.0
Stockholders' equity			(1.5)	0.0
Ending balance			(1.5)
Unrealized Gains (Losses) on Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(10.9)	(11.4)	(29.8)
Other comprehensive income (loss) before reclassifications	(3.0)	(4.7)	6.6
Amounts reclassified from accumulated other comprehensive income (loss)	13.9	11.9	11.5
Other comprehensive income (loss), net of tax	10.9	7.2	18.1
Ending balance	0.0	(10.9)	(11.4)
Unrealized Gains (Losses) on Cash Flow Hedges | Cumulative Effect, Period of Adoption, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		(6.7)	0.3
Stockholders' equity			(6.7)	0.3
Ending balance			(6.7)
Pension and Postretirement Benefit Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(51.5)	(45.0)	(40.4)
Other comprehensive income (loss) before reclassifications	(11.2)	(8.2)	(6.0)
Amounts reclassified from accumulated other comprehensive income (loss)	2.3	1.7	1.4
Other comprehensive income (loss), net of tax	(8.9)	(6.5)	(4.6)
Ending balance	$ (60.4)	(51.5)	(45.0)
Pension and Postretirement Benefit Plans | Cumulative Effect, Period of Adoption, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		$ 0.0	0.0
Stockholders' equity			0.0	$ 0.0
Ending balance			$ 0.0