Income Taxes - Deferred Taxes (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Inventory	$ 569	$ 753
Net operating loss carryforwards	1,898	2,272
Tax credit carryforwards	760	491
Capital loss carryforwards	1,168	1,077
Reserves and accruals	629	655
Intangible assets	1,138	1,299
Stock options	322	585
Other	65	35
Total deferred tax assets	6,549	7,167
Deferred tax liabilities:
Property and equipment	(1,203)	(571)
Goodwill	(2,932)	(3,956)
Foreign branch deferred offset	(1,177)	(1,374)
Other	(44)	(43)
Total deferred tax liabilities	(5,356)	(5,944)
Net deferred tax assets before valuation allowance	1,193	1,223
Valuation allowance	(1,991)	(1,765)
Net deferred tax liability	(798)	(542)
Deferred tax classification
Long-term deferred tax asset	1,378	1,399
Long-term deferred tax liability	(2,176)	(1,941)
Net long-term deferred tax liability	$ (798)	$ (542)