Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Inventory	$ 9,086	$ 9,846
Inventory reserve	7,807	7,079
Allowance for doubtful accounts	396	430
Reserve for accrued liabilities	370	183
Stock options	4,323	4,242
Other	2,969	2,058
Total deferred tax assets	24,951	23,838
Deferred tax liability:
Property, plant and equipment	(9,804)	(9,926)
Net deferred tax asset	$ 15,147	$ 13,912