Financial Risks - Summary of Unused Amount in Funding With Issuance Limit (Detail) - JPY (¥) ¥ in Millions |
Mar. 31, 2025 |
Mar. 31, 2024 |
|---|---|---|
| Disclosure Of Unused Amount In Funding With Issuance Limit [Line Items] | ||
| Unused amount | ¥ 7,253,072 | ¥ 7,718,625 |
| Corporate bonds and medium-term notes [Member] | ||
| Disclosure Of Unused Amount In Funding With Issuance Limit [Line Items] | ||
| Unused amount | 6,011,789 | 6,477,572 |
| Commercial papers [Member] | ||
| Disclosure Of Unused Amount In Funding With Issuance Limit [Line Items] | ||
| Unused amount | ¥ 1,241,283 | ¥ 1,241,053 |