Warranty Reserve - Summary of Warranty Reserve Activity Included in Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Guarantees [Abstract]
Balance at beginning of period	$ 362	$ 514	$ 492	$ 510
Additions	50	306	92	344
Releases and/or charges incurred	(118)	(98)	(290)	(132)
Balance at end of period	$ 294	$ 722	$ 294	$ 722