v3.26.1
Investments - Realized Gains and Losses on Sales of Available-for-Sale Securities (Detail) - JPY (¥)
¥ in Millions
12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Debt Securities, Available-for-sale [Line Items]      
Gross realized gains ¥ 34,290 ¥ 14,153 ¥ 34,287
Gross realized losses (113,063) (29,821) (51,384)
Net realized gains (losses) on sales of available-for-sale securities ¥ (78,773) ¥ (15,668) ¥ (17,097)