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Contents of Significant Accounts - Summary of Balances of Contract Assets and Contract Liabilities (Detail) $ in Thousands, $ in Thousands | Dec. 31, 2024 TWD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 TWD ($) | Jan. 01, 2023 TWD ($)
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Disclosure of balances of contract assets and contract liabilities [line items] |  |  |  |
Contract assets, current | $ 625,713 |  | $ 739,528 | $ 373,318
Contract liabilities, current | 2,200,561 | $ 67,111 | 3,250,712 | 3,546,815
Contract liabilities, non-current | 459,620 | $ 14,017 | 430,640 | 438,188
Contract liabilities | 2,660,181 |  | 3,681,352 | 3,985,003
Sales of Goods and Services [member] |  |  |  |
Disclosure of balances of contract assets and contract liabilities [line items] |  |  |  |
Contract assets, current | 1,043,680 |  | 1,132,477 | 766,691
Contract liabilities | 2,660,181 |  | 3,681,352 | 3,985,003
Loss allowance [member] |  |  |  |
Disclosure of balances of contract assets and contract liabilities [line items] |  |  |  |
Contract assets, current | $ (417,967) |  | $ (392,949) | $ (393,373)

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- Definition The amount of an entity’s obligation to transfer goods or services to a customer for which the entity has received consideration (or the amount is due) from the customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2024-01-01 -Paragraph 105 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2024-en-r&anchor=para_105&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2024-01-01 -Paragraph 116 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2024-en-r&anchor=para_116_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of current contract liabilities. [Refer: Contract liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2024-01-01 -Paragraph 105 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2024-en-r&anchor=para_105&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of non-current contract liabilities. [Refer: Contract liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2024-01-01 -Paragraph 105 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2024-en-r&anchor=para_105&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition Disclosure of balances of contract assets and contract liabilities. + References No definition available. + Details
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