Leases - Cash Paid (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 27, 2020	Dec. 29, 2019	Dec. 30, 2018
Leases [Abstract]
Finance lease - cash paid for interest	$ 2.6	$ 2.5
Finance lease - financing cash flows	0.6	0.5	$ 0.0
Operating lease - operating cash flows (fixed payments)	$ 12.7	$ 14.8