Shareholders' equity - Changes in shares of common stock outstanding (Detail) - shares |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
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| Stockholders' Equity [Abstract] | |||
| Common stock outstanding at beginning of year | 2,956,210,965 | 2,970,755,160 | 3,003,679,324 |
| Decrease of common stock by cancellation of treasury stock | (75,000,000) | (70,000,000) | |
| Common stock held in treasury: | |||
| Repurchases of common stock | (99,361,149) | (63,523,657) | (80,617,143) |
| Sales of common stock | 298 | 115 | 534 |
| Common stock issued to employees | 44,489,127 | 48,981,222 | 47,695,273 |
| Cancellation of treasury stock | 75,000,000 | 70,000,000 | |
| Other net change in treasury stock | (2,017) | (1,875) | (2,828) |
| Common stock outstanding at end of year | 2,901,337,224 | 2,956,210,965 | 2,970,755,160 |
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- Definition Increase Decrease Treasury Shares Other No definition available.
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- References No definition available.
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares issued during the period as a result of an employee stock purchase plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of treasury shares or units reissued. Excludes reissuance of shares or units in treasury for award under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares of common and preferred stock retired from treasury during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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