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Financial Risk and Fair Value Disclosures - Reconciliation for Fair Value Measurement in Level 3 Fair Value Hierarchy (Detail) $ in Thousands, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 TWD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 TWD ($)
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | $ 546,576,832 |  |
Ending balance | 560,168,955 | $ 17,083,530 | $ 546,576,832
Level 3 [member] | Financial assets at fair value through profit or loss [member] |  |  |
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | 10,251,085 |  | 10,726,873
Recognized in profit (loss) | 203,424 |  | (1,216,735)
Recognized in other comprehensive income (loss) | 0 |  | 0
Acquisition | 2,329,820 |  | 1,353,205
Disposal | (566,983) |  | (117,737)
Return of capital | (12,488) |  | (37,730)
Transfer out of Level 3 | (377,121) |  | (461,403)
Exchange effect | 301,052 |  | 4,612
Ending balance | 12,128,789 |  | 10,251,085
Level 3 [member] | Financial assets at fair value through profit or loss [member] | Common stock [member] |  |  |
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | 3,036,255 |  | 3,198,808
Recognized in profit (loss) | (119,584) |  | (312,149)
Recognized in other comprehensive income (loss) | 0 |  | 0
Acquisition | 505,538 |  | 610,153
Disposal | (78,234) |  | 0
Return of capital | (83) |  | (1,384)
Transfer out of Level 3 | (377,121) |  | (461,403)
Exchange effect | 41,412 |  | 2,230
Ending balance | 3,008,183 |  | 3,036,255
Level 3 [member] | Financial assets at fair value through profit or loss [member] | Preferred stocks [member] |  |  |
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | 2,786,634 |  | 2,865,258
Recognized in profit (loss) | 187,131 |  | (277,994)
Recognized in other comprehensive income (loss) | 0 |  | 0
Acquisition | 639,779 |  | 294,046
Disposal | (311,066) |  | (89,997)
Return of capital | 0 |  | 0
Transfer out of Level 3 | 0 |  | 0
Exchange effect | 101,455 |  | (4,679)
Ending balance | 3,403,933 |  | 2,786,634
Level 3 [member] | Financial assets at fair value through profit or loss [member] | Funds [member] |  |  |
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | 4,274,896 |  | 4,626,333
Recognized in profit (loss) | 128,617 |  | (617,764)
Recognized in other comprehensive income (loss) | 0 |  | 0
Acquisition | 1,133,312 |  | 294,245
Disposal | (81,371) |  | 0
Return of capital | (12,405) |  | (36,346)
Transfer out of Level 3 | 0 |  | 0
Exchange effect | 153,398 |  | 8,428
Ending balance | 5,596,447 |  | 4,274,896
Level 3 [member] | Financial assets at fair value through profit or loss [member] | Convertible bonds [member] |  |  |
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | 0 |  | 36,474
Recognized in profit (loss) | 3,120 |  | (8,828)
Recognized in other comprehensive income (loss) | 0 |  | 0
Acquisition | 51,191 |  | 0
Disposal | 0 |  | (27,740)
Return of capital | 0 |  | 0
Transfer out of Level 3 | 0 |  | 0
Exchange effect | 455 |  | 94
Ending balance | 54,766 |  | 0
Level 3 [member] | Financial assets at fair value through profit or loss [member] | Others [Member] |  |  |
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | 153,300 |  | 0
Recognized in profit (loss) | 4,140 |  | 0
Recognized in other comprehensive income (loss) | 0 |  | 0
Acquisition | 0 |  | 154,761
Disposal | (96,312) |  | 0
Return of capital | 0 |  | 0
Transfer out of Level 3 | 0 |  | 0
Exchange effect | 4,332 |  | (1,461)
Ending balance | 65,460 |  | 153,300
Level 3 [member] | Financial assets at fair value through other comprehensive income [member] |  |  |
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | 3,237,388 |  | 3,610,267
Recognized in profit (loss) | 0 |  | 0
Recognized in other comprehensive income (loss) | 134,316 |  | (372,879)
Acquisition | 64,694 |  | 0
Disposal | 0 |  | 0
Return of capital | 0 |  | 0
Transfer out of Level 3 | 0 |  | 0
Exchange effect | 0 |  | 0
Ending balance | 3,436,398 |  | 3,237,388
Level 3 [member] | Financial assets at fair value through other comprehensive income [member] | Common stock [member] |  |  |
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | 3,062,325 |  | 3,427,720
Recognized in profit (loss) | 0 |  | 0
Recognized in other comprehensive income (loss) | 104,499 |  | (365,395)
Acquisition | 64,694 |  | 0
Disposal | 0 |  | 0
Return of capital | 0 |  | 0
Transfer out of Level 3 | 0 |  | 0
Exchange effect | 0 |  | 0
Ending balance | 3,231,518 |  | 3,062,325
Level 3 [member] | Financial assets at fair value through other comprehensive income [member] | Preferred stocks [member] |  |  |
Disclosure of fair value measurement of assets [line items] |  |  |
Beginning balance | 175,063 |  | 182,547
Recognized in profit (loss) | 0 |  | 0
Recognized in other comprehensive income (loss) | 29,817 |  | (7,484)
Acquisition | 0 |  | 0
Disposal | 0 |  | 0
Return of capital | 0 |  | 0
Transfer out of Level 3 | 0 |  | 0
Exchange effect | 0 |  | 0
Ending balance | $ 204,880 |  | $ 175,063

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