Leases - Lease Term and Discount Rate (Details)	Sep. 26, 2020	Dec. 28, 2019
Leases [Abstract]
Operating leases, weighted average remaining lease term (months)	78 months	82 months
Finance leases, weighted average remaining lease term (months)	83 months	88 months
Operating leases, weighted average discount rate (percent)	4.70%	4.60%
Finance leases, weighted average discount rate (percent)	12.50%	13.10%