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Contents of Significant Accounts - Summary of Assumptions Used for Compensation Cost for Cash-settled Share-based Payment Measured at Fair Value on Grant Date by using Black-Scholes Option Pricing Model (Detail) - Stock Appreciation Right Plan For Employees [Member] | 12 Months Ended
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Dec. 31, 2023 yr $ / shares
Granted in September 2020 [Member] |
Statement [Line Items] |
Share price of measurement date (NT$/ per share) | $ / shares | $ 52.6
Expected volatility | 23.95%
Expected life | 0.67
Expected dividend yield | 6.02%
Risk-free interest rate | 1.06%
Granted in June 2021 [Member] |
Statement [Line Items] |
Share price of measurement date (NT$/ per share) | $ / shares | $ 52.6
Expected dividend yield | 6.02%
Bottom of range [member] | Granted in June 2021 [Member] |
Statement [Line Items] |
Expected volatility | 23.21%
Expected life | 0.44
Risk-free interest rate | 1.06%
Top of range [member] | Granted in June 2021 [Member] |
Statement [Line Items] |
Expected volatility | 28.72%
Expected life | 1.44
Risk-free interest rate | 1.08%

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- Definition The percentage of an expected dividend used to calculate the fair value of the cash-settled share-based payment. + References No definition available. + Details
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- Definition The expected life used to calculate the fair value of the cash-settled share-based payment. + References No definition available. + Details
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- Definition The expected volatility used to calculate the fair value of the cash-settled share-based payment. + References No definition available. + Details
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- Definition The risk-free interest rate used to calculate the fair value of the cash-settled share-based payment. + References No definition available. + Details
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- Definition The share price of measurement date used to calculate the fair value of the cash-settled share-based payment. + References No definition available. + Details
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- References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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