Common Stock and Capital Surplus (Changes in Number of Issued Shares of Common Stock) (Detail) - Common stock - shares |
12 Months Ended | ||
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Mar. 31, 2025 |
Mar. 31, 2024 |
Mar. 31, 2023 |
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| Common Stock and Capital Surplus Disclosure [Line Items] | |||
| Balance at the beginning of fiscal year (in shares) | 12,337,710,920 | 12,687,710,920 | 13,281,995,120 |
| Retirement of shares of common stock (in shares) | (270,000,000) | (350,000,000) | (594,284,200) |
| Balance at the end of fiscal year (in shares) | 12,067,710,920 | 12,337,710,920 | 12,687,710,920 |
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- Definition Common Stock and Capital Surplus Disclosure [Line Items] 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 that have been repurchased and retired during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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