Franchise Rights (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Finite-Lived Intangible Assets [Line Items]
Franchise agreement, term			20 years
Franchise RIghts Rollforward [Abstract]
Balance, beginning			$ 152,028
Acquisitions of restaurants	$ 290		290
Amortization of intangible assets, franchise rights	(1,800)	$ (1,700)	(3,568)	$ (3,300)
Balance, end	148,750		148,750
Franchise Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets (excluding goodwill)		0	0	0
Franchise RIghts Rollforward [Abstract]
Amortization expense, expected for full fiscal period	7,100		7,100
Amortization expense, next twelve months	7,100		7,100
Second Fiscal Year	7,100		7,100
Third Fiscal Year	7,100		7,100
Fourth Fiscal Year	7,100		7,100
Fifth Fiscal Year	7,100		7,100
Leases, Acquired-in-Place, Market Adjustment [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	200	$ 200	400	$ 400
Franchise RIghts Rollforward [Abstract]
Amortization expense, expected for full fiscal period	800		800
Amortization expense, next twelve months	800		800
Second Fiscal Year	700		700
Third Fiscal Year	600		600
Fourth Fiscal Year	600		600
Fifth Fiscal Year	$ 700		$ 700