v3.26.1
Related Party Transactions - Additional Information (Detail)
¥ in Millions
12 Months Ended
Mar. 31, 2026
JPY (¥)
Loans
Mar. 31, 2025
JPY (¥)
Related Party Transaction [Line Items]    
Number of loans impaired | Loans 0  
Related party loan ¥ 572,031 ¥ 566,583
Related Party    
Related Party Transaction [Line Items]    
Related party loan ¥ 1,030,000 ¥ 1,045,000