v3.26.1
Accumulated Other Comprehensive Income (Before Tax and Net of Tax Changes in Each Component of Accumulated OCI) (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Tax (expense) or benefit ¥ (209,112) ¥ 20,182 ¥ (339,505)
Total 909,432 473,474 1,462,277
Other comprehensive income attributable to Mitsubishi UFJ Financial Group 899,261 323,565 1,366,571
Net unrealized gains (losses) on investment securities:      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Other comprehensive income (loss) before reclassifications, Before tax (282,039) (186,230) (72,820)
Other comprehensive income (loss) before reclassifications, Tax (expense) or benefit 85,043 98,037 11,993
Other comprehensive income (loss) before reclassifications, Net of tax (196,996) (88,193) (60,827)
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Before tax 309,675 166,982 150,646
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Tax (expense) or benefit (98,333) (51,853) (45,320)
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Net of tax 211,342 115,129 105,326
Net change, Before tax 27,636 (19,248) 77,826
Tax (expense) or benefit (13,290) 46,184 (33,327)
Total 14,346 26,936 44,499
Net unrealized gains (losses) on investment securities attributable to noncontrolling interests      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Total (25,637) 83,726 (13,161)
Net unrealized gains (losses) on investment securities attributable to Mitsubishi UFJ Financial Group      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Total 39,983 (56,790) 57,660
Net debt valuation adjustments:      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Other comprehensive income (loss) before reclassifications, Before tax 2,905 14,664 (65,133)
Other comprehensive income (loss) before reclassifications, Tax (expense) or benefit (911) (4,470) 19,944
Other comprehensive income (loss) before reclassifications, Net of tax 1,994 10,194 (45,189)
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Before tax 1,203 1,538 776
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Tax (expense) or benefit (379) (471) (237)
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Net of tax 824 1,067 539
Net change, Before tax 4,108 16,202 (64,357)
Tax (expense) or benefit (1,290) (4,941) 19,707
Total 2,818 11,261 (44,650)
Net debt valuation adjustments attributable to Mitsubishi UFJ Financial Group      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Total 2,818 11,261 (44,650)
Net unrealized gains (losses) on derivatives qualifying for cash flow hedges:      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Other comprehensive income (loss) before reclassifications, Before tax (9,981) (5,668) 7,441
Other comprehensive income (loss) before reclassifications, Tax (expense) or benefit 3,035 1,153 (1,515)
Other comprehensive income (loss) before reclassifications, Net of tax (6,946) (4,515) 5,926
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Before tax 816 3,585 (8,197)
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Tax (expense) or benefit (163) (717) 1,635
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Net of tax 653 2,868 (6,562)
Net change, Before tax (9,165) (2,083) (756)
Tax (expense) or benefit 2,872 436 120
Total (6,293) (1,647) (636)
Net unrealized losses on derivatives qualifying for cash flow hedges attributable to noncontrolling interests      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Total (30) (385) (148)
Net unrealized losses on derivatives qualifying for cash flow hedges attributable to Mitsubishi UFJ Financial Group      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Total (6,263) (1,262) (488)
Defined benefit plans:      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Other comprehensive income (loss) before reclassifications, Before tax 356,276 134,302 566,093
Other comprehensive income (loss) before reclassifications, Tax (expense) or benefit (112,600) (42,213) (174,339)
Other comprehensive income (loss) before reclassifications, Net of tax 243,676 92,089 391,754
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Before tax (41,587) (30,034) (13,047)
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Tax (expense) or benefit 13,498 9,261 4,148
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Net of tax (28,089) (20,773) (8,899)
Net change, Before tax 314,689 104,268 553,046
Tax (expense) or benefit (99,102) (32,952) (170,191)
Total 215,587 71,316 382,855
Defined benefit plans attributable to noncontrolling interests      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Total 1,775 (578) 1,813
Defined benefit plans attributable to Mitsubishi UFJ Financial Group      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Total 213,812 71,894 381,042
Foreign currency translation adjustments:      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Other comprehensive income (loss) before reclassifications, Before tax 830,611 380,634 1,252,155
Other comprehensive income (loss) before reclassifications, Tax (expense) or benefit (113,293) 3,255 (160,753)
Other comprehensive income (loss) before reclassifications, Net of tax 717,318 383,889 1,091,402
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Before tax (49,335) (26,481) (16,132)
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Tax (expense) or benefit 14,991 8,200 4,939
Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Net of tax (34,344) (18,281) (11,193)
Net change, Before tax 781,276 354,153 1,236,023
Tax (expense) or benefit (98,302) 11,455 (155,814)
Total 682,974 365,608 1,080,209
Foreign currency translation adjustments attributable to noncontrolling interests      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Total 34,063 67,146 107,202
Foreign currency translation adjustments attributable to Mitsubishi UFJ Financial Group      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Total ¥ 648,911 ¥ 298,462 ¥ 973,007