Inventories - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Inventory Disclosure [Abstract]
Amounts credited to the allowance for obsolete inventory	$ 680	$ 566	$ (105)
Items charged to the allowance for inventory write-offs	$ 200	$ 500	$ 0