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Contents of Significant Accounts - Summary of Stock Held by Associates (Detail) - shares shares in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Disclosure Of Stock Held By Associates [Line Items] |  |  |
Number of shares in entity held by its subsidiaries or associates |  | 900,961 | 900,961
HSUN CHIEH [member] |  |  |
Disclosure Of Stock Held By Associates [Line Items] |  |  |
Number of shares in entity held by its subsidiaries or associates |  | 441,371 | 441,371
YANN YUAN [member] |  |  |
Disclosure Of Stock Held By Associates [Line Items] |  |  |
Number of shares in entity held by its subsidiaries or associates |  | 192,963 | 192,963
SUBTRON, the subsidiary of UNIMICRON [member] |  |  |
Disclosure Of Stock Held By Associates [Line Items] |  |  |
Number of shares in entity held by its subsidiaries or associates | [1] | 47 | 47
SIS [member] |  |  |
Disclosure Of Stock Held By Associates [Line Items] |  |  |
Number of shares in entity held by its subsidiaries or associates | [2] | 266,580 | 266,580
[1] | Beginning from January 2023, SUBTRON becomes an associate of the Company.
[2] | Beginning from August 2023, SIS becomes an associate of the Company.

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