v3.26.1
Employee benefits - Summary of Employee Benefit Expense (Detail) - JPY (¥)
¥ in Millions
12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Disclosure of Detailed Information About Employee Benefits Expense [Line Items]      
Total employee benefits expenses ¥ 1,784,569 ¥ 1,840,803 ¥ 1,743,936