Income Taxes (Reconciliation of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Beginning and Ending amount of Unrecognized tax benefits
Unrecognized Tax Benefit, Beginning of Period	$ 3.7	$ 0.9	$ 1.2
Gross Increases to Tax Positions Related to Current Year	0.0	0.5	0.1
Gross Increases to Tax Positions Related to Prior Years	0.1	2.6	0.0
Gross Decreases to Tax Positions Related to Prior Years	(0.5)	0.0	(0.1)
Gross Decreases related to settlements with taxing authorities	0.0	0.0	(0.1)
Expiration of Statute of Limitations	(1.2)	(0.3)	(0.2)
Unrecognized Tax Benefit, End of Period	$ 2.1	$ 3.7	$ 0.9