v3.26.1
Other Financial Assets - Additional Information (Detail) - JPY (¥)
¥ in Millions
Mar. 31, 2026
Mar. 31, 2025
Securities Loaned [Member] | Public and corporate bonds [Member]    
Statement [Line Items]    
Financial assets measured at fair value through other comprehensive income include securities loaned amount ¥ 2,594,946 ¥ 623,223