Basis of Presentation and Summary of Significant Accounting Policies - Reclassified franchise and restaurant revenues and expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total franchise expenses	$ 330,619	$ 293,986	$ 293,500
Company restaurant expenses	5,872	7,838	18,224
Franchisor [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue from contract with customer, excluding assessed Tax	643,934	594,418	637,971
Food and Beverage [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue from contract with customer, excluding assessed Tax	$ 7,084	7,518	17,367
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Franchise and restaurant revenues		475,030	501,745
Franchise and Restaurant Expenses		171,983	162,860
Total franchise expenses		164,145	144,636
Company restaurant expenses		7,838	18,224
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Franchisor [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue from contract with customer, excluding assessed Tax		467,512	484,378
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Food and Beverage [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue from contract with customer, excluding assessed Tax		$ 7,518	$ 17,367