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Contents of Significant Accounts - Details of Investments Accounted for Under the Equity Method (Detail) $ in Thousands, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 TWD ($) | Dec. 31, 2022 TWD ($) | Dec. 31, 2023 USD ($)
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 32,785,800 | $ 26,504,913 | $ 1,070,731
SILICON INTEGRATED SYSTEMS CORP. (SIS) [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 2,373,060 | $ 0 |
Percentage of ownership or voting rights, Associates | 19.02% | 0.00% |
FARADAY TECHNOLOGY CORP. (FARADAY) [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 1,990,073 | $ 1,862,245 |
Percentage of ownership or voting rights, Associates | 13.78% | 13.78% |
UNIMICRON TECHNOLOGY CORP. (UNIMICRON) [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 13,644,560 | $ 13,285,169 |
Percentage of ownership or voting rights, Associates | 13.05% | 13.27% |
MTIC HOLDINGS PTE. LTD. [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 0 | $ 0 |
Percentage of ownership or voting rights, Associates | 45.44% | 45.44% |
UNITECH CAPITAL INC. [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 625,667 | $ 426,070 |
Percentage of ownership or voting rights, Associates | 42.00% | 42.00% |
TRIKNIGHT CAPITAL CORPORATION (TRIKNIGHT) [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 2,109,906 | $ 2,117,678 |
Percentage of ownership or voting rights, Associates | 40.00% | 40.00% |
HSUN CHIEH CAPITAL CORP. [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 235,098 | $ 210,690 |
Percentage of ownership or voting rights, Associates | 40.00% | 40.00% |
PURIUMFIL INC. [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 11,474 | $ 14,622 |
Percentage of ownership or voting rights, Associates | 40.00% | 40.00% |
HSUN CHIEH INVESTMENT CO., LTD. (HSUN CHIEH) [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 4,126,878 | $ 2,980,984 |
Percentage of ownership or voting rights, Associates | 36.49% | 36.49% |
YANN YUAN INVESTMENT CO., LTD. (YANN YUAN) [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 7,516,327 | $ 5,455,743 |
Percentage of ownership or voting rights, Associates | 26.78% | 26.78% |
UNITED LED CORPORATION HONG KONG LIMITED [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 93,793 | $ 97,156 |
Percentage of ownership or voting rights, Associates | 25.14% | 25.14% |
VSENSE CO., LTD. [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 0 | $ 0 |
Percentage of ownership or voting rights, Associates | 23.98% | 23.98% |
TRANSLINK CAPITAL PARTNERS I, L.P. [member] |  |  |
Investments in associates and joint ventures [line items] |  |  |
Amount | $ 58,964 | $ 54,556 |
Percentage of ownership or voting rights, Associates | 10.38% | 10.38% |

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- Definition The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2023-01-01 -Paragraph 24 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2023-en-r&anchor=para_24_a&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2023-01-01 -Paragraph B16 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2023-en-r&anchor=para_B16&doctype=Appendix&subtype=B -URIDate 2023-03-23 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 54 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_54_e&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2023-01-01 -Paragraph 17 -Subparagraph b -Clause iii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=27&code=ifrs-tx-2023-en-r&anchor=para_17_b_iii&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2023-01-01 -Paragraph 16 -Subparagraph b -Clause iii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=27&code=ifrs-tx-2023-en-r&anchor=para_16_b_iii&doctype=Standard -URIDate 2023-03-23 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2023-01-01 -Paragraph 21 -Subparagraph a -Clause iv -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2023-en-r&anchor=para_21_a_iv&doctype=Standard -URIDate 2023-03-23 + Details
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