Leases Maturity of Operating Lease LIability (Details) - USD ($) $ in Thousands	Jun. 27, 2020	Dec. 28, 2019	Dec. 30, 2018
Leases [Abstract]
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	$ 4,308
Lessee, Operating Lease, Liability, Payments, Due Year Two	8,529
Lessee, Operating Lease, Liability, Payments, Due Year Three	8,245
Lessee, Operating Lease, Liability, Payments, Due Year Four	7,345
Lessee, Operating Lease, Liability, Payments, Due Year Five	6,508
Lessee, Operating Lease, Liability, Payments, Due after Year Five	34,963
Lessee, Operating Lease, Liability, Payments, Due	69,898
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	10,405
Operating Lease, Liability	59,493		$ 67,300
Current portion of operating lease liabilities	6,674	$ 6,843
Operating Lease, Liability, Noncurrent	$ 52,819	$ 54,928