Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid insurance	$ 5,857	$ 6,711
Prepaid marketing and advertising costs	3,821	2,800
Other	9,022	6,799
Total prepaid expenses and other current assets	$ 18,700	$ 16,310