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Significant Related Party Transactions - Significant Transactions between Company and Other Related Parties (Detail) ¥ in Thousands, shares in Thousands, $ in Thousands, $ in Thousands | 12 Months Ended |  |
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Dec. 31, 2024 TWD ($) shares | Dec. 31, 2024 USD ($) shares | Dec. 31, 2023 TWD ($) shares | Dec. 31, 2022 TWD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2024 CNY (¥) | Dec. 31, 2023 CNY (¥)
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Accounts receivable-related parties, net | $ 620,013 |  | $ 347,964 |  | $ 18,909 |  |
Acquisition of investments accounted for under the equity method, Purchase price | 33,274,869 |  | 32,785,800 |  | $ 1,014,787 |  |
Acquisition of intangible assets | 2,799,420 | $ 85,374 | 2,546,516 | $ 2,756,155 |  |  |
Disposal of subsidiary ownership |  |  | 0 | 0 |  |  |
Trading Capital Amount | ¥ |  |  |  |  |  |  | ¥ 4,416,624
Purchase price |  |  | 21,209,443 |  |  |  |
SIS - SIS SEMICONDUCTOR (SHANDONG) CO., LTD [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Gain on disposal | 352 |  |  |  |  |  |
Disposal price | 341,387 |  |  |  |  |  |
Trading capital | ¥ |  |  |  |  |  | ¥ 30,000 |
FARADAY TECHNOLOGY CORP. [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Acquisition of investments accounted for under the equity method, Purchase price | 2,484,001 |  | 1,990,073 |  |  |  |
Acquisition of intangible assets | 310,460 |  | 323,551 | 266,053 |  |  |
FARADAY TECHNOLOGY CORP. [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Accounts receivable-related parties, net | 456,332 |  | 302,828 |  |  |  |
ARTERY TECHNOLOGY CORPORATION, LTD. [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Accounts receivable-related parties, net | 148,508 |  | 40,886 |  |  |  |
Associates [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Operating revenues | 3,611,015 |  | 3,018,171 | 5,744,098 |  |  |
Associates [member] | Stock of FARADAY [Member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Acquisition of investments accounted for under the equity method, Purchase price | $ 533,973 |  |  |  |  |  |
Acquisition of investments accounted for under the equity method, Trading Volume | shares | 1,723 | 1,723 |  |  |  |  |
Associates [member] | Stock Of UNIMICRON [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Acquisition of investments accounted for under the equity method, Purchase price |  |  | $ 608,224 |  |  |  |
Acquisition of investments accounted for under the equity method, Trading Volume | shares |  |  | 4,945 |  |  |  |
Other related party [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Operating revenues | $ 0 |  | $ 4,463 | 40,474 |  |  |
Mask expenditure | 2,285,797 |  | 2,375,225 | 2,581,409 |  |  |
Other payables of mask expenditure | 621,737 |  | 751,763 | 812,185 |  |  |
All other related parties [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Operating revenues | 3,611,015 |  | 3,022,634 | $ 5,784,572 |  |  |
Others [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Accounts receivable-related parties, net | 493 |  | 3,602 |  |  |  |
Other Associates [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Accounts receivable-related parties, net | $ 14,680 |  | 648 |  |  |  |
XIAMEN JINYUAN INDUSTRIAL DEVELOPMENT CO., LTD. [member] | Increase of ownership stake in the subsidiary company USCXM [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Trading Capital Amount | ¥ |  |  |  |  |  |  | 3,741,862
Purchase price |  |  | 17,945,970 |  |  |  |
FUJIAN ELECTRONICS & INFORMATION INDUSTRY ENTREPRENEURSHIP INVESTMENT LIMITED PARTNERSHIP [member] | Increase of ownership stake in the subsidiary company USCXM [member] |  |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |  |
Trading Capital Amount | ¥ |  |  |  |  |  |  | ¥ 674,762
Purchase price |  |  | $ 3,263,473 |  |  |  |

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