Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2021	Sep. 29, 2020	Sep. 28, 2021	Sep. 29, 2020	Dec. 29, 2020
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected unredeemed percent			9.00%
Estimated redemption period			24 months
Gift card liability, current	$ 2,189		$ 2,189		$ 2,551
Revenue recognized for redemption of gift cards	600	$ 600	$ 2,500	$ 2,800
Period in which initial fees received from franchisees will be recognized as revenue			20 years
Contract with Customer, Liability, Current	200		$ 200		400
Accrued Expenses and Other Current Liabilities
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Gift card liability, current	2,200		2,200		2,600
Other Long-term Liabilities
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Gift card liability, non-current	$ 400		$ 400		$ 600