Leases - Weighted Average (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2021	Jun. 28, 2020	Jun. 27, 2021	Jun. 28, 2020
Leases [Abstract]
Operating lease liabilities arising from obtaining right-of-use assets	$ 1.7	$ 0.5	$ 1.9	$ 1.0
Finance lease liabilities arising from obtaining right-of-use assets	$ 0.0	$ 0.0	$ 0.0	$ 0.4
Weighted-average remaining lease term (in years):
Operating leases	5 years 1 month 2 days	5 years 7 months 2 days	5 years 1 month 2 days	5 years 7 months 2 days
Finance leases	17 years 2 months 19 days	18 years 5 months 4 days	17 years 2 months 19 days	18 years 5 months 4 days
Weighted-average discount rate:
Operating leases	6.50%	6.47%	6.50%	6.47%
Finance leases	6.51%	6.52%	6.51%	6.52%