v3.26.1
Foreign Activities (Estimated Financial Information by Geographic Areas) (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Foreign Activities Disclosure [Line Items]      
Total revenue ¥ 11,867,264 ¥ 10,836,109 ¥ 10,032,704
Total expense 9,357,769 9,040,533 8,154,478
Income (loss) before income tax expense (benefit) 2,509,495 1,795,576 1,878,226
Net income attributable to Mitsubishi UFJ Financial Group 1,729,359 1,266,933 1,325,869
Total assets at end of fiscal year 425,581,652 405,940,211 397,820,570
Domestic, Japan      
Foreign Activities Disclosure [Line Items]      
Total revenue 4,407,092 2,905,946 3,824,225
Total expense 3,737,025 3,015,746 2,695,960
Income (loss) before income tax expense (benefit) 670,067 (109,800) 1,128,265
Net income attributable to Mitsubishi UFJ Financial Group 270,426 (343,745) 930,001
Total assets at end of fiscal year 254,932,299 261,732,514 257,518,304
　United States of America      
Foreign Activities Disclosure [Line Items]      
Total revenue 3,283,133 3,179,967 2,578,487
Total expense 1,999,441 2,141,975 2,210,134
Income (loss) before income tax expense (benefit) 1,283,692 1,037,992 368,353
Net income attributable to Mitsubishi UFJ Financial Group 1,196,575 903,188 456,755
Total assets at end of fiscal year 80,069,950 66,393,043 61,312,679
Foreign, Europe      
Foreign Activities Disclosure [Line Items]      
Total revenue 956,645 1,321,415 598,995
Total expense 1,123,782 1,014,249 692,351
Income (loss) before income tax expense (benefit) (167,137) 307,166 (93,356)
Net income attributable to Mitsubishi UFJ Financial Group (277,182) 219,445 (239,793)
Total assets at end of fiscal year 28,386,626 23,652,847 23,578,110
Foreign, Asia / Oceania Excluding Japan      
Foreign Activities Disclosure [Line Items]      
Total revenue 2,078,650 2,173,457 2,079,886
Total expense 1,792,496 2,038,743 1,849,365
Income (loss) before income tax expense (benefit) 286,154 134,714 230,521
Net income attributable to Mitsubishi UFJ Financial Group 132,051 115,817 (77,661)
Total assets at end of fiscal year 42,930,411 38,556,319 39,486,295
Foreign, Other areas      
Foreign Activities Disclosure [Line Items]      
Total revenue 1,141,744 1,255,324 951,111
Total expense 705,025 829,820 706,668
Income (loss) before income tax expense (benefit) 436,719 425,504 244,443
Net income attributable to Mitsubishi UFJ Financial Group 407,489 372,228 256,567
Total assets at end of fiscal year ¥ 19,262,366 ¥ 15,605,488 ¥ 15,925,182