Goodwill and Other Intangible Assets (Amortization Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of other intangible assets	$ 18.8	$ 10.7	$ 10.5
Finite-lived intangible assets, next twelve months	18.1
Finite-lived intangible assets, year two	16.0
Finite-lived intangible assets, year three	16.0
Finite-lived intangible assets, year four	15.8
Finite-lived intangible assets, year five and thereafter	89.5
Total	$ 155.4