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Significant Subsequent Events - Additional Information (Detail) ¥ in Millions, $ in Millions, $ in Millions | Apr. 02, 2024 CNY (¥) | Mar. 22, 2024 TWD ($) | Apr. 30, 2024 USD ($) | Feb. 27, 2024 USD ($)
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Purchase Of Interests In Associates [member] | FARADAY TECHNOLOGY CORP. [member] |  |  |  |
Disclosure of subsidiaries [line items] |  |  |  |
Purchase of interests in associates |  | $ 534 |  |
7V AI CAPITAL LLC [member] | Authorization to contribute additional capital to the subsidiary company [member] | Top of range [member] | UMC Capital Corp. [Member] |  |  |  |
Disclosure of subsidiaries [line items] |  |  |  |
The amount the parent company participate in the capital increase of a subsidiary |  |  | $ 22 |
7V AI CAPITAL LLC [member] | Authorization to contribute capital to the investee company [member] | Top of range [member] | UMC Capital Corp. [Member] |  |  |  |
Disclosure of subsidiaries [line items] |  |  |  |
The amount the Board of Directors of a subsidiary approved an investment in a company |  |  |  | $ 20
HEJIAN TECHNOLOGY (SUZHOU) CO., LTD [member] | Disposal of major subsidiary [member] | UNITEDDS SEMICONDUCTOR (SHANDONG) CO., LTD. [member] |  |  |  |
Disclosure of subsidiaries [line items] |  |  |  |
Disposal of ownership interest in the subsidiary percentage | 100.00% |  |  |
Consideration Receivable On Disposal Of Subsidiary | ¥ | ¥ 77 |  |  |

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