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Inventories - Cost of Inventories Recognized as an Expense (Detail) $ in Thousands, $ in Thousands | 12 Months Ended
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Dec. 31, 2020 TWD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 TWD ($) | Dec. 31, 2018 TWD ($)
Analysis of income and expense [abstract] |  |  |  |
Cost of revenue | $ 17,957,568 |  | $ 16,372,032 | $ 15,057,605
Loss on abandonment | 5,323 |  | 12,369 | 5,497
Allowance for (reversal of) inventory valuation and obsolescence loss | 16,317 |  | 27,341 | (13,070)
Cost of revenue | $ 17,979,208 | $ 640,285 | $ 16,411,742 | $ 15,050,032

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- Definition The amount of inventories recognised as an expense during the period. [Refer: Inventories] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 2 -IssueDate 2020-01-01 -Paragraph 36 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=2&code=ifrs-tx-2020-en-r&anchor=para_36_d&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount of costs relating to expenses directly or indirectly attributed to the goods or services sold, which may include, but are not limited to, costs previously included in the measurement of inventory that has now been sold, unallocated production overheads and abnormal amounts of production costs of inventories. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 99 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_99&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 103 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_103&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount recognised resulting from the write-down of inventories to net realisable value or reversals of those write-downs. [Refer: Inventories] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 98 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_98_a&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition Loss on abandonment, inventory. + References No definition available. + Details
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