Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Tax Cuts and Jobs Act, Transition Tax for Accumulated Foreign Earnings, Income Tax Expense		$ 0.9
Undistributed foreign earnings, deferred tax liability	$ 1.4	2.4
Valuation Allowance, Deferred Tax Asset, Change in Amount	18.7	(116.1)
Unrecognized tax benefits	41.2	37.3	$ 42.0	$ 29.0
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	41.2
Unrecognized tax benefits, income tax penalties and interest accrued	7.6	6.2
Interest and penalties, net of tax, related to uncertain tax positions	1.9	1.3
Unrecognized Tax Benefits, Decreases Resulting from Settlements with Taxing Authorities	$ 14.8
Reassessment of future realizability of deferred taxes due to Tax Reform
Tax Cuts and Jobs Act, Measurement Period Adjustment, Income Tax Expense (Benefit)		$ 22.8