Inventory Valued at Lower of Cost (First-in, First-out) or Net Realizable Value, Net of Inventory Obsolescence Reserve (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Inventory [Line Items]
Raw materials	$ 3,158	$ 5,204
Finished goods	78,062	70,231
Inventory, net	$ 81,220	$ 75,435