Intangible Assets and Goodwill - Components of Company's Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Finite Lived Intangible Assets [Line Items]
Net Balance	$ 91,538		$ 91,538		$ 103,157
Amortization expense	5,200	$ 5,300	15,500	$ 14,400
Franchise agreements
Finite Lived Intangible Assets [Line Items]
Initial Cost	180,867		180,867		180,867
Accumulated Amortization	(89,329)		(89,329)		(77,710)
Net Balance	91,538		$ 91,538		103,157
Franchise agreements | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets			12 years 6 months
Other intangible assets
Finite Lived Intangible Assets [Line Items]
Initial Cost	36,624		$ 36,624		30,875
Accumulated Amortization	(11,678)		(11,678)		(7,910)
Net Balance	24,946		$ 24,946		22,965
Other intangible assets | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets			5 years
Software
Finite Lived Intangible Assets [Line Items]
Initial Cost	27,824		$ 27,824		20,579
Accumulated Amortization	(8,534)		(8,534)		(5,802)
Net Balance	19,290		$ 19,290		14,777
Software | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets			4 years 3 months 18 days
Trademarks
Finite Lived Intangible Assets [Line Items]
Initial Cost	1,900		$ 1,900		1,857
Accumulated Amortization	(988)		(988)		(839)
Net Balance	912		$ 912		1,018
Trademarks | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets			9 years 3 months 18 days
Software Development
Finite Lived Intangible Assets [Line Items]
Capitalized software development costs	8,200		$ 8,200		4,500
Non-compete agreements
Finite Lived Intangible Assets [Line Items]
Initial Cost	3,700		3,700		3,700
Accumulated Amortization	(1,383)		(1,383)		(896)
Net Balance	2,317		$ 2,317		2,804
Non-compete agreements | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets			7 years 8 months 12 days
Training materials
Finite Lived Intangible Assets [Line Items]
Initial Cost	2,400		$ 2,400		2,350
Accumulated Amortization	(520)		(520)		(157)
Net Balance	1,880		$ 1,880		2,193
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	800		$ 800		2,389
Accumulated Amortization	(253)		(253)		(216)
Net Balance	$ 547		$ 547		$ 2,173
Other | Weighted Average
Finite Lived Intangible Assets [Line Items]
Useful life of intangible assets			5 years