Leases - Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Loans and Leases Receivable Disclosure [Line Items]
Variable lease cost	$ 3,599	$ 4,290	$ 7,704	$ 8,090
Sublease income	(106)	(143)	(228)	(321)
Amortization of right-of-use assets	437	523	882	999
Interest on lease liabilities	36	64	82	135
Total lease cost	29,624	27,425	59,667	49,962
Restaurant Rent Expense [Member]
Loans and Leases Receivable Disclosure [Line Items]
Operating lease cost	25,491	22,543	50,962	40,837
General and Administrative Expense [Member]
Loans and Leases Receivable Disclosure [Line Items]
Operating lease cost	$ 167	$ 148	$ 265	$ 222