Revenue Recognition - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2020	Dec. 31, 2019	Jan. 01, 2019	Jan. 03, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Gift card liability, current	$ 2,551	$ 2,398
Revenue recognized for redemption of gift cards	3,500	5,300	$ 5,900
Gift card breakage	$ 300	400	$ 1,000
Period in which initial fees received from franchisees will be recognized as revenue	20 years
Deferred revenue	$ 427	555
Initial fees from franchisees
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue recognized that was included in contract liability	100
Accrued expenses and other current liabilities
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Gift card liability, current	2,600	2,400
Other long-term liabilities
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Gift card liability, non-current	$ 600	$ 900
Difference between Revenue Guidance in Effect before and after Topic 606 | ASU No. 2014-09 | Initial fees from franchisees
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract liability				$ 1,500