Other assets - Office buildings, land, equipment and facilities and Other / Other liabilities - Schedule of change in asset retirement obligation (Detail) - JPY (¥) ¥ in Millions |
12 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
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| Other assets-Other / Other liabilities [Abstract] | ||
| Balance at beginning of year | ¥ 16,193 | ¥ 15,512 |
| Provision for the year | 757 | 161 |
| Settled during the year | (233) | (413) |
| Revisions in estimated cash flows | 5,219 | 933 |
| Balance at end of year | ¥ 21,936 | ¥ 16,193 |
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- Definition Other assets-Other / Other liabilities No definition available.
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- Definition The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of asset retirement obligations incurred during the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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