v3.26.1
Other Assets - Schedule of Other Assets (Parenthetical) (Details) - JPY (¥)
¥ in Millions
12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Disclosure Of Other Assets [Abstract]    
Straight-line basis over the period 10 years  
Amortization expenses ¥ 4,473 ¥ 4,464