Employee Benefits - Changes in Present Value of Defined Benefit Obligations and Fair Value of Plan Assets (Parenthetical) (Detail) - JPY (¥) ¥ in Millions |
Mar. 31, 2026 |
Mar. 31, 2025 |
|---|---|---|
| Disclosure of net defined benefit liability (asset) [line items] | ||
| Net defined benefit liabilities (assets) | ¥ 187,988 | ¥ 185,835 |