v3.26.3
Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Disclosure In Tabular Form Of Allowances For Credit Losses And Provision For Credit Losses (Parenthetical) (Detail) - JPY (¥)
¥ in Millions
Sep. 30, 2026
Mar. 31, 2026
Disclosure in Tabular Form of Allowances for Credit Losses and Provision for Credit Losses [Abstract]    
Allowance for credit losses on off balance sheet exposures ¥ 17,175 ¥ 17,611
Allowance for credit loss on available for sale debt securities ¥ 3,354 ¥ 3,505