Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 16, 2020	Jun. 18, 2019
Leases [Abstract]
Operating cash flows used for operating leases	$ 15,749	$ 14,238
Operating cash flows used for finance leases	18	51
Financing cash flows used for finance leases	$ 87	$ 243