Leases - Lease Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 25, 2022	Dec. 26, 2021
Leases [Abstract]
Amortization of right of use assets - finance leases	$ 2.9	$ 2.4
Interest expense on lease liabilities - finance leases	3.0	2.7
Operating lease cost (expense resulting from amortization of total lease payments)	12.9	11.2
Short-term lease cost	0.8	0.8
Variable lease cost (cost excluded from lease payments)	0.1	0.1
Sublease income	0.0	(0.2)
Total lease cost	$ 19.7	$ 17.0