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Stock - Estimated Fair Value of Restricted Stock Units on Dates of Each Grant Using Binomial Option Pricing Model (Detail) - Restricted Stock Units (RSUs) [Member] - Employee Stock Incentive Master Scheme Two Thousand And Twenty Two [Member] | 12 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2023
Share Based Compensation By Share Based Award Restricted Stock Units Valuation Assumptions [Line Items] |  |  |
Expected volatility, lower range | 20.32% | 21.32% | 23.68%
Expected volatility, upper range | 27.55% | 35.35% | 35.35%
Risk-free interest rate, lower range | 6.84% | 6.85% | 7.07%
Risk-free interest rate, upper range | 6.89% | 7.18% | 7.57%
Maximum [Member] |  |  |
Share Based Compensation By Share Based Award Restricted Stock Units Valuation Assumptions [Line Items] |  |  |
Dividend yield | 1.20% | 1.17% | 0.75%
Expected term (in years) | 4 years | 4 years | 4 years
Minimum [Member] |  |  |
Share Based Compensation By Share Based Award Restricted Stock Units Valuation Assumptions [Line Items] |  |  |
Dividend yield | 0.77% | 0.65% | 0.47%
Expected term (in years) | 1 year | 1 year | 1 year

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- Definition Share Based Compensation By Share Based Award Restricted Stock Units Valuation Assumptions + References No definition available. + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The estimated measure of the maximum 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. + References No definition available. + Details
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- Definition The estimated measure of the minimum 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. + References No definition available. + Details
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- Definition The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. + References No definition available. + Details
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. + References No definition available. + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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