Revenue Recognition - Contract Liabilities (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 26, 2021	Jun. 27, 2021	Mar. 28, 2021	Sep. 27, 2020	Jun. 28, 2020	Mar. 29, 2020	Sep. 26, 2021	Sep. 27, 2020	Dec. 31, 2020	Dec. 31, 2019
Contract with Customer, Asset
Contract Assets					$ 0.3	$ 0.3				$ 0.4
Change in period				$ (0.3)		(0.1)
Contract Liabilities
Contract Liabilities - Current	$ 14.8	$ 14.5	$ 14.5	12.8	11.7	11.7	$ 14.8	$ 12.8	$ 13.5	11.5
Increase (decrease) - Current Liabilities	0.3		1.0	1.1		0.2
Contract Liabilities - Noncurrent	2.5	2.4	2.3	2.7	2.7	2.8	2.5	2.7	$ 2.5	$ 2.9
Increase (decrease) - Noncurrent Liabilities	0.1	$ 0.1	$ (0.2)		$ (0.1)	$ (0.1)
Revenue recognized, contract liability	$ 3.2			$ 2.2			11.7	7.0
Impairment loss related to Contract Assets							$ 0.0	$ 0.0