Impairment of Long-Lived Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Impaired Long-Lived Assets Held and Used
Impairment of long-lived assets	$ 0	$ 347	$ 1,684	$ 2,156
Surplus properties
Impaired Long-Lived Assets Held and Used
Impairment of long-lived assets	0	229	1,397	270
Company-operated restaurants
Impaired Long-Lived Assets Held and Used
Impairment of long-lived assets	0	0	287	1,603
Restaurants leased or subleased to franchisees
Impaired Long-Lived Assets Held and Used
Impairment of long-lived assets	$ 0	$ 118	$ 0	$ 283