Intangible Assets and Goodwill - Components of Company's Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite Lived Intangible Assets [Line Items]
Initial Cost	$ 54,704	$ 45,484
Accumulated Amortization	(24,735)	(13,169)
Net Balance	72,196	87,670
Net Balance	29,969	32,315
Amortization expense	24,900	20,600	$ 19,500
Franchise agreements
Finite Lived Intangible Assets [Line Items]
Initial Cost	180,867	180,867
Accumulated Amortization	(108,671)	(93,197)
Net Balance	$ 72,196	87,670
Franchise agreements | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets	12 years 6 months
Other intangible assets | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets	4 years 8 months 12 days
Software
Finite Lived Intangible Assets [Line Items]
Initial Cost	$ 44,389	36,680
Accumulated Amortization	(18,926)	(9,653)
Net Balance	$ 25,463	27,027
Capitalized software development costs		10,500
Software | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets	4 years 6 months
Trademarks
Finite Lived Intangible Assets [Line Items]
Initial Cost	$ 2,325	1,904
Accumulated Amortization	(1,274)	(1,037)
Net Balance	$ 1,051	867
Trademarks | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets	8 years 4 months 24 days
Software Development
Finite Lived Intangible Assets [Line Items]
Capitalized software development costs	$ 1,400	10,500
Non-compete agreements
Finite Lived Intangible Assets [Line Items]
Initial Cost	3,920	3,700
Accumulated Amortization	(2,814)	(1,546)
Net Balance	$ 1,106	2,154
Non-compete agreements | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets	4 years 4 months 24 days
Training materials
Finite Lived Intangible Assets [Line Items]
Initial Cost	$ 2,400	2,400
Accumulated Amortization	(1,120)	(640)
Net Balance	$ 1,280	1,760
Training materials | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets	5 years
Other
Finite Lived Intangible Assets [Line Items]
Initial Cost	$ 1,670	800
Accumulated Amortization	(601)	(293)
Net Balance	$ 1,069	$ 507
Other | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets	5 years 3 months 18 days