Business Developments (Pro Forma Statements Of Operations) (Details) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
HC Philippines
Business Developments [Line Items]
Total revenue		¥ 68,177	¥ 49,790
Net income (loss) attributable to Mitsubishi UFJ Financial Group		3,775	5,256
HC Indonesia
Business Developments [Line Items]
Total revenue		28,201	24,180
Net income (loss) attributable to Mitsubishi UFJ Financial Group		(220)	(299)
PT Mandala Multifinance Tbk
Business Developments [Line Items]
Total revenue		20,580	19,733
Net income (loss) attributable to Mitsubishi UFJ Financial Group		1,416	3,014
Albacore Capital Group
Business Developments [Line Items]
Total revenue		8,279	7,780
Net income (loss) attributable to Mitsubishi UFJ Financial Group		859	¥ (712)
Link Administration Holdings Limited
Business Developments [Line Items]
Total revenue	¥ 114,723	128,252
Net income (loss) attributable to Mitsubishi UFJ Financial Group	2,746	17,445
WealthNavi Inc
Business Developments [Line Items]
Total revenue	11,172	8,173
Net income (loss) attributable to Mitsubishi UFJ Financial Group	¥ (1,255)	¥ (1,388)

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/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479907/805-20-50-5

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 2
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