Revenue Recognition (Net Contract Assets(Liabilities)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Revenue Recognition and Deferred Revenue [Abstract]
Contract with Customer, Liability, Revenue Recognized	$ 4.8
Contract with Customer, Asset, Net	2.5	$ 2.1
Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	$ 0.4
Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress, Percent	19.00%
Contract with Customer, Liability, Current	$ 13.0	7.3
Contract with Customer, Liability, Current, Net, Change in Timeframe, Performance Obligation Satisfied Revenue Recognized	$ (5.7)
Contract with Customer, Liability, Current, Net, Change in Timeframe, Performance Obligation Satisfied Revenue Recognized, Percent	78.10%
Contract with Customer, Liability, Noncurrent	$ 5.9	5.5
Contract with Customer, Liability, Noncurrent, Net, Change in Timeframe, Performance Obligation Satisfied Revenue Recognized	$ (0.4)
Contract with Customer, Liability, Noncurrent, Net, Change in Timeframe, Performance Obligation Satisfied Revenue Recognized, Percent	7.30%
Contract with Customer, Asset (Liability), Net	$ (16.4)	$ (10.7)
Contract with Customer, Asset (Liability), Change in Timeframe, Performance Obligation Satisfied Revenue Recognized	$ (5.7)