Supplemental cash flow information - Additional Information (Detail) - JPY (¥) ¥ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
Mar. 31, 2023 |
|
| Disclosure of supplement cash flow information [Line Items] | |||
| Other, net | ¥ 494,551 | ¥ 1,392,565 | ¥ (207,829) |
| Net increase in time deposits [Member] | |||
| Disclosure of supplement cash flow information [Line Items] | |||
| Other, net | ¥ 666,401 | ¥ 1,395,707 | |