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Contents of Significant Accounts - Major Categories of Plan Assets as a Percentage of Fair Value of the Total Plan Assets (Detail) | Dec. 31, 2023 | Dec. 31, 2022
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Disclosure Of Fair Value Of Plan Assets [Abstract] |  |
Cash | 21.00% | 20.00%
Equity instruments | 46.00% | 47.00%
Debt instruments | 23.00% | 22.00%
Others | 10.00% | 11.00%

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- Definition Percentage of debt instruments in the plan assets. + References No definition available. + Details
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