Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 02, 2019	Apr. 03, 2018	Jan. 02, 2019	Jan. 01, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected unredeemed percent	9.00%
Estimated redemption period	24 months
Gift card liability	$ 1,906			$ 3,284
Gift card breakage	$ 1,800	$ 1,800
Period in which initial fees received from franchisees will be recognized as revenue	20 years
Retained earnings	$ (118,978)		$ (117,127)	(111,135)
Accrued Expenses and Other Current Liabilities
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Gift card liability	1,900			3,300
Other Long-term Liabilities
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Gift card liability, non-current	$ 700			$ 400