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Contents of Significant Accounts - Equity - Additional Information (Detail) |  |  | 12 Months Ended
--- | --- | --- | ---
Dec. 05, 2023 shares $ / shares | Dec. 05, 2022 shares $ / shares | Dec. 31, 2023 shares $ / shares | Dec. 31, 2022 shares $ / shares
Disclosure of classes of share capital [line items] |  |  |  |
Shares authorized |  |  | 26,000,000,000 | 26,000,000,000
Shares issued |  |  | 12,529,822,000 | 12,504,749,000
Shares par value | $ / shares |  |  | $ 10 | $ 10
Number of common shares represented by 1 ADS |  |  | 5 |
Percentage of legal reserve |  |  | 10.00% |
Cash dividends | $ / shares |  |  |  | $ 3.60046348
American depositary shares [member] |  |  |  |
Disclosure of classes of share capital [line items] |  |  |  |
Number of American Depositary Shares traded on NYSE |  |  | 121,000,000 | 135,000,000
Number of common shares represented by issued American Depositary Shares |  |  | 607,000,000 | 674,000,000
Bottom of range [member] |  |  |  |
Disclosure of classes of share capital [line items] |  |  |  |
Percentage of cash dividend on dividend distribution |  |  | 20.00% |
Percentage of stock dividend on dividend distribution |  |  | 0.00% |
Top of range [member] |  |  |  |
Disclosure of classes of share capital [line items] |  |  |  |
Percentage of cash dividend on dividend distribution |  |  | 100.00% |
Percentage of stock dividend on dividend distribution |  |  | 80.00% |
Restricted Stocks [member] |  |  |  |
Disclosure of classes of share capital [line items] |  |  |  |
Shares par value | $ / shares | $ 10 | $ 10 |  |
Number of other equity instruments granted in share-based payment arrangement | 27,000,000 | 23,000,000 |  |
Number of other equity instruments recalled and cancelled in share-based payment arrangement |  |  | 2,000,000 | 2,000,000

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