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Segments - Additional Information (Detail)	3 Months Ended		9 Months Ended
Segments - Additional Information (Detail)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) segment	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			3
Number of operating segments \| segment			0
Revenue	$ 105,383,000	$ 166,815,000	$ 272,847,000	$ 497,292,000
Franchise revenue
Segment Reporting Information [Line Items]
Revenue	59,757,000	66,709,000	139,288,000	204,283,000
Franchise revenue \| Placement Services
Segment Reporting Information [Line Items]
Revenue	1,455,000	4,277,000	4,335,000	12,112,000
Corporate-owned stores
Segment Reporting Information [Line Items]
Revenue	28,289,000	$ 40,742,000	78,224,000	$ 118,481,000
Corporate-owned stores \| Canada
Segment Reporting Information [Line Items]
Long-lived assets	$ 850,000		850,000		$ 1,039,000
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue			$ 0