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Significant Contingencies and Unrecognized Contract Commitments - Additional Information (Detail) ¥ in Millions, $ in Millions, $ in Millions | Jan. 27, 2022 TWD ($) | Dec. 31, 2023 TWD ($) | Dec. 31, 2023 CNY (¥) | Jul. 31, 2023 CNY (¥) | Jul. 31, 2023 USD ($)
--- | --- | --- | --- | --- | ---
Disclosure of contingent liabilities [line items] |  |  |  |  |
Amounts available under unused letters of credit |  | $ 33,200 |  |  |
Litigations, electricity supply and customs tax guarantee |  | 2,200 |  |  |
Patent license agreements and development contracts of intellectual property, contract amount |  | 3,800 |  |  |
Royalties and development fees not yet recognized |  | 1,200 |  |  |
Construction contracts, amount |  | 70,600 |  |  |
Construction contracts not yet recognized |  | $ 38,400 |  |  |
Final Decision By The Authority [Member] | Micron Technology [Member] | Intellecutal Property And Commercial Court [Member] |  |  |  |  |
Disclosure of contingent liabilities [line items] |  |  |  |  |
Amount of fine | $ 20 |  |  |  |
Probation period | 2 years |  |  |  |
UNITED SEMICONDUCTOR (XIAMEN) CO., LTD. (USCXM) [member] |  |  |  |  |
Disclosure of contingent liabilities [line items] |  |  |  |  |
Amount of investment in subsidiaries | ¥ |  |  | ¥ 8,300 |  |
Repurchase from the other investors of their investments | ¥ |  |  | ¥ 4,900 |  |
Investments in subsidiaries by entity |  |  |  | ¥ 4,120 | $ 660
Additional Investment by entity subsidiary |  |  |  | 740 | $ 120
Cumulative investment in subsidiary by group | ¥ |  |  |  | ¥ 4,900 |

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