Income Taxes - Tax Cuts and Jobs Act of 2017 (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax [Line Items]
Expense (benefit) to tax expense due to reduction of DTL recorded for non-US earnings considered not permanently invested	$ 9.2
Tax expense related to non-United States withholding tax		$ 5.5
Deferred tax liability, undistributed foreign earnings	15.3	5.5
Transition tax expense	(6.0)	170.2
Impact on net deferred assets and liabilities, excluding the provision for unremitted earnings	$ 0.0	$ 1.2
United States
Income Tax [Line Items]
Statutory rate	21.00%	35.00%	35.00%
Scenario, Previously Reported
Income Tax [Line Items]
Expense (benefit) to tax expense due to reduction of DTL recorded for non-US earnings considered not permanently invested		$ (275.8)