Segments - Summary of Financial Information for the Company's Reportable Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 181,661	$ 140,550	$ 330,478	$ 261,882
Total Segment EBITDA	74,399	56,928	134,173	104,503
Corporate And Other Non Segment
Segment Reporting Information [Line Items]
Total Segment EBITDA	(10,370)	(9,236)	(23,932)	(17,978)
Franchise revenue
Segment Reporting Information [Line Items]
Revenue	71,812	58,150	137,574	112,762
Franchise revenue | Operating Segments
Segment Reporting Information [Line Items]
Total Segment EBITDA	49,860	40,041	97,220	76,719
Franchise revenue | US
Segment Reporting Information [Line Items]
Revenue	70,221	57,252	134,618	110,697
Franchise revenue | International
Segment Reporting Information [Line Items]
Revenue	1,591	898	2,956	2,065
Corporate-owned Stores
Segment Reporting Information [Line Items]
Revenue	39,695	34,252	77,739	66,959
Corporate-owned Stores | Operating Segments
Segment Reporting Information [Line Items]
Total Segment EBITDA	18,137	14,666	33,706	26,837
Corporate-owned Stores | US
Segment Reporting Information [Line Items]
Revenue	38,592	33,125	75,541	64,697
Corporate-owned Stores | International
Segment Reporting Information [Line Items]
Revenue	1,103	1,127	2,198	2,262
Equipment revenue
Segment Reporting Information [Line Items]
Revenue	70,154	48,148	115,165	82,161
Equipment revenue | Operating Segments
Segment Reporting Information [Line Items]
Total Segment EBITDA	16,772	11,457	27,179	18,925
Equipment revenue | US
Segment Reporting Information [Line Items]
Revenue	$ 70,154	$ 48,148	$ 115,165	$ 82,161