Revenue (Contract Balances) (Details) - USD ($) $ in Millions	Mar. 30, 2018	Jan. 01, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract assets	$ 140.3	$ 89.2
Current contract liabilities	50.7	75.6
Non-current contract liabilities	$ 0.6	0.6
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract assets		51.1
Current contract liabilities		(24.9)
Non-current contract liabilities		$ 0.0