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Segments - Additional Information (Detail)	3 Months Ended		6 Months Ended
Segments - Additional Information (Detail)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			3
Number of operating segments \| segment			0
Revenue	$ 40,234,000	$ 181,661,000	$ 167,464,000	$ 330,478,000
Franchise revenue
Segment Reporting Information [Line Items]
Revenue	21,002,000	71,812,000	79,531,000	137,574,000
Franchise revenue \| Placement Services
Segment Reporting Information [Line Items]
Revenue	868,000	5,071,000	2,880,000	7,836,000
Corporate-owned stores
Segment Reporting Information [Line Items]
Revenue	9,419,000	$ 39,695,000	49,935,000	$ 77,739,000
Corporate-owned stores \| Canada
Segment Reporting Information [Line Items]
Long-lived assets	$ 867,000		867,000		$ 1,039,000
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue			$ 0