Revenue (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 935.0				$ 897.8				$ 935.0	$ 897.8	$ 870.5		$ 761.6
Retained Earnings (Accumulated Deficit)	725.1				694.0				725.1	694.0	678.1
Sales Revenue, Goods, Net	1,851.6	$ 1,877.9	$ 1,763.0	$ 1,773.2	1,816.7	$ 1,981.4	$ 1,948.0	$ 1,777.8	7,265.7	7,523.9	7,202.5
Contract assets, contract liabilities, or deferred contract costs recorded
Accounting Standards Update 2014-09 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest											0.8
Revision of Prior Period, Change in Accounting Principle, Adjustment [Member] | Accounting Standards Update 2014-09 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest												$ 0.8
Retained Earnings (Accumulated Deficit)												$ (0.3)
Sales Revenue, Goods, Net											0.2
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Retained Earnings (Accumulated Deficit)											0.9
Sales Revenue, Goods, Net											$ 0.2