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Income Tax - Summary of Unused Investment Credits (Detail) - 12 months ended Dec. 31, 2017 $ in Thousands, $ in Thousands | TWD ($) | USD ($)
--- | --- | ---
Unused tax credits [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Remaining Creditable Amount | $ 534,213 | $ 18,023
Purchase of machinery and equipment [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Expiry Year | 2018 |
Purchase of machinery and equipment [member] | Unused tax credits [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Remaining Creditable Amount | $ 518,790 | 17,503
Others [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Expiry Year | 2,022 and thereafter |
Others [member] | Unused tax credits [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Remaining Creditable Amount | $ 15,423 | $ 520

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- Definition The amount of deferred tax liabilities net of deferred tax assets, when the absolute amount of deferred tax liabilities is greater than the absolute amount of deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_g_i&doctype=Standard -URIDate 2017-03-09 + Details
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- Details
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