Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Rental revenues									$ 121,934	$ 121,437	$ 123,037
Revenues	$ 214,198	$ 194,099	$ 184,471	$ 188,163	$ 176,708	$ 174,903	$ 188,654	$ 191,461	780,931	731,725	787,566
Gross profit (loss), by segment									110,608	(428,309)	157,851
Total interest expense									71,000	72,700	73,700
Depreciation and amortization									32,175	30,648	30,606
Impairment of goodwill and intangible assets						$ 531,600			0	531,634	0
Closure and other impairment charges									2,107	3,968	5,092
Impairment of goodwill and intangible assets and closure and other impairment charges									2,100	535,600	5,100
Capital expenditures									14,279	13,370	5,637
Goodwill (franchise segment)	345,314				339,236				345,314	339,236	697,400	$ 697,400
Total assets	1,774,680				1,735,612				1,774,680	1,735,612	2,278,600
Corporate
Segment Reporting Information [Line Items]
Interest expense									61,700	62,000	61,500
Depreciation and amortization									9,600	7,700	7,200
Closure and other impairment charges									0	0	2,900
Capital expenditures									14,300	13,300	5,300
Total assets	226,800				181,300				226,800	181,300	115,400
Operating Segments
Segment Reporting Information [Line Items]
Gross profit (loss), by segment									353,100	338,700	384,200
Operating Segments
Segment Reporting Information [Line Items]
Capital expenditures										100	300
Operating Segments | Franchise operations
Segment Reporting Information [Line Items]
Gross profit (loss), by segment									313,300	300,400	344,500
Depreciation and amortization									10,500	10,800	10,600
Impairment of goodwill and intangible assets									0	531,600	0
Total assets	1,152,100				1,188,000				1,152,100	1,188,000	1,608,700
Operating Segments | Rental operations
Segment Reporting Information [Line Items]
Rental revenues									121,900	121,400	123,000
Gross profit (loss), by segment									31,200	30,800	31,500
Interest expense									9,200	10,500	11,800
Depreciation and amortization									11,700	12,000	12,400
Total assets	255,600				278,800				255,600	278,800	339,500
Operating Segments | Company restaurants
Segment Reporting Information [Line Items]
Gross profit (loss), by segment									1,200	(300)	(800)
Interest expense									100	200	400
Depreciation and amortization									400	100	400
Closure and other impairment charges									2,100	4,000	2,200
Capital expenditures									0
Total assets	66,500				0				66,500	0	126,800
Operating Segments | Financing operations
Segment Reporting Information [Line Items]
Gross profit (loss), by segment									7,400	7,800	9,000
Total assets	$ 73,700				$ 87,500				73,700	87,500	88,200
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Gross profit (loss), by segment									(242,500)	(767,000)	(226,300)
Financial Service [Member]
Segment Reporting Information [Line Items]
Revenue from contract with customer, excluding assessed tax									7,979	8,352	9,191
Financial Service [Member] | Operating Segments | Financing operations
Segment Reporting Information [Line Items]
Revenue from contract with customer, excluding assessed tax									8,000	8,400	9,200
Franchisor [Member]
Segment Reporting Information [Line Items]
Revenue from contract with customer, excluding assessed tax									643,934	594,418	637,971
Franchisor [Member] | Operating Segments | Franchise operations
Segment Reporting Information [Line Items]
Revenue from contract with customer, excluding assessed tax									643,900	594,400	638,000
Food and Beverage [Member]
Segment Reporting Information [Line Items]
Revenue from contract with customer, excluding assessed tax									7,084	$ 7,518	17,367
Food and Beverage [Member] | Operating Segments | Company restaurants
Segment Reporting Information [Line Items]
Revenue from contract with customer, excluding assessed tax									$ 7,100		$ 17,400