Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Tax Credit Carryforward [Line Items]
Tax Cuts and Jobs Act, provisional income tax expense (benefit)	$ 56.5
Tax Cuts and Jobs Act, measurement period adjustment income tax benefit			$ 6.0
Income tax credits		$ 26.9	24.5
Loss carryforwards		21.3	22.2
Valuation allowance		29.0	21.8
Undistributed earnings of foreign subsidiaries		250.0
Income taxes paid		91.9	106.3	$ 130.8
Unrecognized tax benefits timing of deductibility unknown		5.2
Unrecognized tax benefits, income tax penalties and interest expense		0.1	1.8	$ 0.5
Unrecognized tax benefits, income tax penalties and interest accrued		7.1	$ 7.0
Minimum
Tax Credit Carryforward [Line Items]
Unrecognized tax benefits that would impact effective tax rate		33.4
Decrease in unrecognized tax benefits is reasonably possible, estimated range of change		5.0
Maximum
Tax Credit Carryforward [Line Items]
Decrease in unrecognized tax benefits is reasonably possible, estimated range of change		7.0
Federal, State, and Local
Tax Credit Carryforward [Line Items]
Loss carryforwards		20.1
Tax credit carryforward indefinitely
Tax Credit Carryforward [Line Items]
Income tax credits		15.5
Loss carryforwards		7.4
Carryforward Subject To Expiration
Tax Credit Carryforward [Line Items]
Income tax credits		11.4
Loss carryforwards		$ 12.7