Inventories - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Raw materials	$ 5,269	$ 7,978
Work-in-process	12,322	9,505
Finished products	58,964	42,434
Deferred cost of sales	3,569	3,429
Total inventory	$ 80,124	$ 63,346