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Net Operating Loss Carryforwards available to Offset Future Taxable Income (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($)
Operating Loss Carryforwards [Line Items] |
Amount | $ 57,089
Hong Kong |
Operating Loss Carryforwards [Line Items] |
Amount | $ 15,760
Expiring year | Indefinite
Taiwan |
Operating Loss Carryforwards [Line Items] |
Amount | $ 41,329
Taiwan | Earliest Tax Year |
Operating Loss Carryforwards [Line Items] |
Expiring year | 2021
Taiwan | Latest Tax Year |
Operating Loss Carryforwards [Line Items] |
Expiring year | 2030

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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
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