Segments - Summary of Company's Goodwill by Reportable Segment (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total consolidated goodwill	$ 199,513	$ 176,981	$ 176,981	$ 176,981
Franchise revenue
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total consolidated goodwill	16,938		16,938
Corporate-owned stores
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total consolidated goodwill	89,909		67,377
Equipment revenue
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total consolidated goodwill	$ 92,666		$ 92,666	$ 92,666