Inventory (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Finished goods	$ 639	$ 724
Work-in-process	2,942	3,386
Inventory, gross	3,581	4,110
Reserve for excess, obsolete or unsalable inventory	(981)	(1,265)
Inventory, net	$ 2,600	$ 2,845