Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Tax expense (benefit)	$ 6.0		$ 2.9	$ 18.5	$ 5.1
Effective tax rate	9.90%		7.10%	16.20%	5.10%
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			$ 3.5		$ 3.5
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred tax liabilities, undistributed foreign earnings						$ 9.8
Tax Cuts and Jobs Act of 2017, incomplete Accounting, Change in tax rate, provisional income tax expense	$ 4.8	$ 0.3		$ 4.8
Accounting Standards Update 2016-09 [Member]
Income Tax Disclosure [Abstract]
Tax expense (benefit)	$ 3.4		$ 9.6	$ 5.5	$ 25.5