Leases Supplemental Lease Information (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 26, 2020	Sep. 28, 2019
Supplemental Lease Information [Abstract]
Operating Lease, Weighted Average Remaining Lease Term		7 years 10 months 20 days	6 years 2 months 12 days
Finance Lease, Weighted Average Remaining Lease Term	[1]	11 years 8 months 15 days	11 years 9 months 18 days
Operating Lease, Weighted Average Discount Rate, Percent		6.93%	8.51%
Finance Lease, Weighted Average Discount Rate, Percent	[1]	9.08%	6.69%
Operating Lease, Payments		$ 3,706	$ 2,534
Interest paid for financing leases	[1]	1,067	1,039
Finance Lease, Principal Payments	[1]	$ 2,767	$ 3,122

[1] Includes leases classified as failed sale-leaseback transactions.