Revenue from Contracts with Customers - Revenues Disaggregated by Revenue Source and Market (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 30, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Total revenue	$ 110,048	$ 107,721
Core Market
Disaggregation of Revenue [Line Items]
Total revenue	97,175	93,687
Non-Core Market
Disaggregation of Revenue [Line Items]
Total revenue	12,873	14,034
Company-operated restaurant revenue
Disaggregation of Revenue [Line Items]
Total revenue	93,957	94,161
Company-operated restaurant revenue | Core Market
Disaggregation of Revenue [Line Items]
Total revenue	89,627	87,224
Company-operated restaurant revenue | Non-Core Market
Disaggregation of Revenue [Line Items]
Total revenue	4,330	6,937
Franchise revenue
Disaggregation of Revenue [Line Items]
Total revenue	9,255	7,612
Franchise revenue | Core Market
Disaggregation of Revenue [Line Items]
Total revenue	4,350	3,687
Franchise revenue | Non-Core Market
Disaggregation of Revenue [Line Items]
Total revenue	4,905	3,925
Franchise advertising fee revenue
Disaggregation of Revenue [Line Items]
Total revenue	6,836	5,948
Franchise advertising fee revenue | Core Market
Disaggregation of Revenue [Line Items]
Total revenue	3,198	2,776
Franchise advertising fee revenue | Non-Core Market
Disaggregation of Revenue [Line Items]
Total revenue	$ 3,638	$ 3,172