Share-Based Compensation - Expenses (Details) - Selling, General and Administrative Expenses - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 28, 2019	Jun. 29, 2018	Jun. 28, 2019	Jun. 29, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1.9	$ 2.3	$ 6.1	$ 7.0
Stock Options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	0.0	0.0	0.0	0.1
RSUs/PSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	1.8	2.3	5.1	5.9
RSAs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 0.1	$ 0.0	$ 1.0	$ 1.0