v3.26.1
Supplemental cash flow information - Additional Information (Detail) - JPY (¥)
¥ in Millions
12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Disclosure of supplement cash flow information [Line Items]      
Other, net ¥ 1,159,304 ¥ (494,551) ¥ (1,392,565)
Net increase in time deposits [Member]      
Disclosure of supplement cash flow information [Line Items]      
Other, net ¥ 1,292,045 ¥ 666,401