Stock - Estimated Fair Value of Options on Dates of Each Grant Using Binomial Option Pricing Model (Detail) - Employees Stock Option |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
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| Minimum | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Dividend yield | 0.75% | 0.73% | 0.67% |
| Expected volatility | 20.96% | 23.30% | 21.91% |
| Risk-free interest rate, lower range | 6.20% | 6.75% | 7.21% |
| Expected term (in years) | 4 years 8 months 26 days | 4 years 5 months 26 days | 4 years 6 months |
| Maximum | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Dividend yield | 1.09% | 1.03% | 0.71% |
| Expected volatility | 26.41% | 27.70% | 27.42% |
| Risk-free interest rate, upper range | 6.98% | 7.24% | 7.55% |
| Expected term (in years) | 7 years 3 months 21 days | 7 years 2 months 15 days | 7 years 3 months |
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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