Earnings Per Share - Summary of Earnings (Loss) Per Share (Detail) - JPY (¥) ¥ / shares in Units, ¥ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
|
| Earnings per share [abstract] | |||
| Profit (loss) for the year attributable to owners of the parent (millions of yen) | ¥ (423,941) | ¥ 835,837 | ¥ 1,107,174 |
| Weighted average number of common shares outstanding, basic | 3,997,276,887 | 4,671,383,489 | 4,901,560,332 |
| Basic earnings (loss) per share attributable to owners of the parent | ¥ (106.06) | ¥ 178.93 | ¥ 225.88 |