Crypto assets held (Details) - JPY (¥) |
12 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Crypto Assets [Abstract] | ||
| Crypto assets held, current | ¥ 37,876,000,000 | ¥ 44,680,000,000 |
| Crypto assets held, non-current | 186,000,000 | 43,000,000 |
| Crypto assets held, impairment | ¥ 0 | ¥ 0 |