Revenue from Contracts with Customers - Loyalty Reward Liability and Gift Card Liability (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2020	Dec. 25, 2019	Dec. 26, 2018
Change in Contract with Customer, Liability [Roll Forward]
Gift card liability	$ 4,008	$ 3,006
Loyalty reward program
Change in Contract with Customer, Liability [Roll Forward]
Contract with Customer, Liability	1,084	1,048	$ 425
Revenue deferred	2,463	2,395	1,850
Revenue recognized	(2,647)	(2,359)	(1,227)
Contract with Customer, Liability	$ 900	1,084	1,048
Loyalty reward program | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Change in Contract with Customer, Liability [Roll Forward]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Gift card liability | Other Current Liabilities
Change in Contract with Customer, Liability [Roll Forward]
Revenue recognized from gift card liability	$ 880	$ 800	$ 816