Earnings (Loss) Per Common Share Applicable to Common Shareholders of MUFG (Reconciliations of Net Income and Weighted Average Number of Common Shares Outstanding Used for Computation of Basic EPS to Adjusted Amounts for Computation of Diluted EPS) (Detail) - JPY (¥) ¥ / shares in Units, shares in Thousands, ¥ in Millions	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Income (loss) (Numerator):
Net income (loss) attributable to Mitsubishi UFJ Financial Group	¥ 1,328,121	¥ 376,635	¥ (83,320)
Effect of dilutive instruments:
Restricted stock units and performance-based stock units—Morgan Stanley	(3,283)	(3,816)	(5,361)
Earnings (loss) applicable to common shareholders of Mitsubishi UFJ Financial Group for diluted computation	¥ 1,324,838	¥ 372,819	¥ (88,681)
Shares (Denominator):
Weighted average common shares outstanding (in shares)	11,978,725	12,317,723	12,798,060
Effect of dilutive instruments:
Stock acquisition rights under the Stock Option Plan and the common shares of MUFG under the Board Incentive Plan (in shares)	1,876	1,132	0
Weighted average common shares for diluted computation (in shares)	11,980,601	12,318,855	12,798,060
Basic earnings (loss) per common share:
Earnings (loss) applicable to common shareholders of Mitsubishi UFJ Financial Group (in JPY per share)	¥ 110.87	¥ 30.58	¥ (6.51)
Diluted earnings (loss) per common share:
Earnings (loss) applicable to common shareholders of Mitsubishi UFJ Financial Group (in JPY per share)	¥ 110.58	¥ 30.26	¥ (6.93)