Impairment of Long-Lived Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2018	Apr. 02, 2017
Impaired Long-Lived Assets Held and Used
Impairment of long-lived assets	$ 206	$ 510
Restaurants leased or subleased to franchisees
Impaired Long-Lived Assets Held and Used
Impairment of long-lived assets	165	0
Company-operated restaurants
Impaired Long-Lived Assets Held and Used
Impairment of long-lived assets	0	17
Surplus properties
Impaired Long-Lived Assets Held and Used
Impairment of long-lived assets	$ 41	$ 493