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Contents of Significant Accounts - Leases (Detail) $ in Thousands, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 TWD ($) | Dec. 31, 2023 TWD ($) | Dec. 31, 2024 USD ($)
Disclosure Of Lease By Lessee [Line Items] |  |  |
Depreciation | $ 698,651 | $ 691,080 |
Right-of-use assets | 8,039,015 | 7,000,355 | $ 245,167
Current | 636,357 | 514,324 | 19,407
Noncurrent | 5,782,659 | 4,878,863 | $ 176,354
Total | 6,419,016 | 5,393,187 |
Land [member] |  |  |
Disclosure Of Lease By Lessee [Line Items] |  |  |
Depreciation | 377,882 | 377,593 |
Right-of-use assets | 5,755,484 | 5,318,986 |
Buildings [member] |  |  |
Disclosure Of Lease By Lessee [Line Items] |  |  |
Depreciation | 87,486 | 93,610 |
Right-of-use assets | 168,568 | 156,483 |
Machinery and equipment [member] |  |  |
Disclosure Of Lease By Lessee [Line Items] |  |  |
Depreciation | 220,734 | 203,606 |
Right-of-use assets | 2,082,479 | 1,506,824 |
Transportation equipment [member] |  |  |
Disclosure Of Lease By Lessee [Line Items] |  |  |
Depreciation | 10,852 | 13,267 |
Right-of-use assets | 12,561 | 16,356 |
Other property, plant and equipment [member] |  |  |
Disclosure Of Lease By Lessee [Line Items] |  |  |
Depreciation | 1,697 | 3,004 |
Right-of-use assets | $ 19,923 | $ 1,706 |

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- Definition The amount of current lease liabilities. [Refer: Lease liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 47 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_47_b&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of depreciation of right-of-use assets. [Refer: Depreciation and amortisation expense; Right-of-use assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 53 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 47 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_47_b&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of non-current lease liabilities. [Refer: Lease liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 47 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_47_b&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of assets that represent a lessee's right to use an underlying asset for the lease term that do not meet the definition of investment property. Underlying asset is an asset that is the subject of a lease, for which the right to use that asset has been provided by a lessor to a lessee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 53 -Subparagraph j -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_j&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2024-01-01 -Paragraph 47 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_47_a&doctype=Standard -URIDate 2024-03-27 + Details
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