Other assets - Office buildings, land, equipment and facilities and Other / Other liabilities - Additional information (Detail) - JPY (¥) ¥ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
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| Finite-Lived Intangible Assets [Line Items] | |||
| Amortization expenses | ¥ 4,854 | ¥ 2,552 | ¥ 2,479 |
| Indefinite-lived intangibles | 28,756 | 53,123 | |
| Depreciation and amortization | 68,269 | 61,653 | 61,340 |
| Intangible assets with a net carrying value | 114,131 | 3,023 | |
| Macquarie Management Holdings Inc [Member] | |||
| Finite-Lived Intangible Assets [Line Items] | |||
| Intangible assets with a net carrying value | ¥ 112,659 | ||
| Weighted average amortization period | 12 years | ||
| Information processing and communications [Member] | |||
| Finite-Lived Intangible Assets [Line Items] | |||
| Depreciation and amortization | ¥ 51,527 | 47,714 | 47,244 |
| Occupancy and related depreciation [Member] | |||
| Finite-Lived Intangible Assets [Line Items] | |||
| Depreciation and amortization | ¥ 13,703 | ¥ 13,939 | ¥ 14,096 |
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average period before the next renewal or extension (both explicit and implicit) for intangible assets that have been renewed or extended, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount after impairment of indefinite-lived intangible assets classified as other. Excludes financial assets and goodwill. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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