Revenue from Contracts with Customers - Loyalty Reward Liability and Gift Card Liability (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 29, 2021	Sep. 23, 2020	Sep. 29, 2021	Sep. 23, 2020	Dec. 30, 2020
Change in Contract with Customer, Liability [Roll Forward]
Contract with Customer, Liability			$ 5,628	$ 6,317	$ 6,317
Revenue deferred			1,330	10
Contract with Customer, Liability	$ 6,444	$ 5,427	6,444	5,427	5,628
Gift card liability	$ 3,686		3,686		4,008
Revenue recognized from gift card liability			$ 514	900
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-09-30
Change in Contract with Customer, Liability [Roll Forward]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	3 months		3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-12-30
Change in Contract with Customer, Liability [Roll Forward]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year		1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-12-29
Change in Contract with Customer, Liability [Roll Forward]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year		1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-12-28
Change in Contract with Customer, Liability [Roll Forward]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year		1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-12-26
Change in Contract with Customer, Liability [Roll Forward]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year		1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-12-25
Change in Contract with Customer, Liability [Roll Forward]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Loyalty reward program
Change in Contract with Customer, Liability [Roll Forward]
Contract with Customer, Liability			$ 900	1,084	1,084
Revenue deferred			2,030		2,463
Revenue recognized			(2,183)		(2,647)
Contract with Customer, Liability	$ 747		$ 747		900
Loyalty reward program | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Change in Contract with Customer, Liability [Roll Forward]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year		1 year
Gift card liability
Change in Contract with Customer, Liability [Roll Forward]
Gift card liability	$ 3,686		$ 3,686		$ 4,008
Revenue recognized from gift card liability	$ 88	$ 138	$ 1,509	$ 890