Employee benefits - Summary of Sensitivity of the Defined Benefit Obligations (Detail) - Actuarial assumption of discount rates [member] - JPY (¥) ¥ in Millions |
Mar. 31, 2025 |
Mar. 31, 2024 |
|---|---|---|
| Japanese Defined Benefit Plans [Member] | ||
| Disclosure of sensitivity analysis for actuarial assumptions [line items] | ||
| Decrease in significant weighted-average | ¥ 11,336 | ¥ 14,362 |
| Increase in significant weighted-average | (10,878) | (12,077) |
| Foreign Defined Benefit Plan [Member] | ||
| Disclosure of sensitivity analysis for actuarial assumptions [line items] | ||
| Decrease in significant weighted-average | 3,628 | 3,657 |
| Increase in significant weighted-average | ¥ (3,437) | ¥ (3,493) |