Deferred Income Tax Assets (liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Stock-based compensation	$ 2,138	$ 1,339
Allowance for sales return	365	324
Inventory reserve	1,918	1,925
Foreign currency translation	24	47
Property and equipment	(343)	(483)
Investment tax credits	3,251	4,512
Net operating loss carryforwards	18,654	16,754
Others	2,158	1,013
Valuation allowance	(21,807)	(20,816)
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	$ 6,358	$ 4,615

Deferred tax assets (liabilities), property, plant and equipment.

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- Definition

Deferred Tax Assets, Unrealized Currency Exchange Loss (Gain)

+ References

No definition available.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

+ References

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- Definition

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

+ References

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- Definition

Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32621-109319

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32632-109319

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible tax credit carryforwards, classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32632-109319

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32621-109319

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-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32559-109319

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

+ References

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from estimated returns and sales allowances.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

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- References

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