Summary of Significant Accounting Policies - Inventory Valued at Lower of Cost (First-in, First-out) or Market, Net of Inventory Obsolescence Reserve (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Raw materials	$ 144	$ 311
Finished goods	54,115	53,569
Inventory, net	54,259	53,880
Inventory obsolescense reserve	$ 12,900	$ 12,800