Segments - Schedule of Segment Reporting Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Rental revenues	$ 29,207	$ 31,273	$ 87,080	$ 84,797
Total revenues	233,220	228,719	701,437	666,537
Interest expense	17,100	17,700	51,800	54,200
Depreciation and amortization	8,900	10,000	28,870	29,995
Pretax book income (loss)	28,737	30,772	95,425	93,444
Operating Segments
Segment Reporting Information [Line Items]
Pretax book income (loss)	94,300	94,600	282,800	278,800
Corporate
Segment Reporting Information [Line Items]
Interest expense	15,300	15,700	46,200	48,000
Depreciation and amortization	3,200	3,000	9,100	8,800
Pretax book income (loss)	(65,600)	(63,800)	(187,400)	(185,400)
Franchise operations | Operating Segments
Segment Reporting Information [Line Items]
Depreciation and amortization	2,500	2,500	7,500	7,600
Pretax book income (loss)	84,600	85,500	253,800	249,200
Rental operations | Operating Segments
Segment Reporting Information [Line Items]
Rental revenues	29,200	31,300	87,100	84,800
Interest expense	1,100	1,200	3,200	3,800
Depreciation and amortization	2,700	2,800	8,000	8,300
Pretax book income (loss)	7,200	6,800	21,100	18,800
Company restaurants | Operating Segments
Segment Reporting Information [Line Items]
Interest expense	700	800	2,400	2,400
Depreciation and amortization	500	1,700	4,300	5,300
Pretax book income (loss)	1,700	1,400	5,400	7,900
Financing operations | Operating Segments
Segment Reporting Information [Line Items]
Pretax book income (loss)	800	900	2,500	2,900
Franchise Revenue:
Segment Reporting Information [Line Items]
Revenue from contract with customer	164,907	161,126	494,398	469,056
Franchise Revenue: | Franchise operations | Operating Segments
Segment Reporting Information [Line Items]
Revenue from contract with customer	164,900	161,200	494,400	469,100
Company restaurants
Segment Reporting Information [Line Items]
Revenue from contract with customer	38,248	35,275	117,175	109,418
Company restaurants | Company restaurants
Segment Reporting Information [Line Items]
Revenue from contract with customer	38,200	35,200	117,200	109,400
Financing revenues
Segment Reporting Information [Line Items]
Revenue from contract with customer	858	1,045	2,784	3,266
Financing revenues | Financing operations | Operating Segments
Segment Reporting Information [Line Items]
Revenue from contract with customer	$ 900	$ 1,000	$ 2,800	$ 3,300