Other assets - Office buildings, land, equipment and facilities and Other / Other liabilities - Schedule of Other assets-Other and Other liabilities (Parenthetical) (Detail) - JPY (¥) ¥ in Millions |
Mar. 31, 2026 |
Mar. 31, 2025 |
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|---|---|---|---|---|
| Other Assets Other and Other Liabilities [Line Items] | ||||
| Investments in equity securities for other than operating purposes | [1] | ¥ 386,473 | ¥ 302,973 | |
| Other liabilities [Member] | ||||
| Other Assets Other and Other Liabilities [Line Items] | ||||
| Liability in respect of outstanding and unsettled investigations | 13,077 | 14,240 | ||
| Listed equity securities [Member] | ||||
| Other Assets Other and Other Liabilities [Line Items] | ||||
| Investments in equity securities for other than operating purposes | 15,776 | 5,889 | ||
| Unlisted equity securities [Member] | ||||
| Other Assets Other and Other Liabilities [Line Items] | ||||
| Investments in equity securities for other than operating purposes | ¥ 370,642 | ¥ 297,085 | ||
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