Premises and Equipment (Narrative) (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Property, Plant and Equipment [Line Items]
Impairment losses for long-lived assets	¥ 2,941	¥ 5,317	¥ 6,574
Impairment, Long-Lived Asset, Held-for-Use, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other non-interest expenses (Notes 5 and 26)
Real estate
Property, Plant and Equipment [Line Items]
Impairment of assets held for sale	¥ 5,468	¥ 174	¥ 58

Indicates line item in statement of income or comprehensive income that includes impairment of long-lived asset held for use.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482099/360-10-50-2

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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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.

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No definition available.

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