v3.26.1
Segment Information - Additional Information (Detail) - JPY (¥)
¥ in Millions
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Disclosure of operating segments [line items]      
Total assets ¥ 105,522,331 ¥ 93,601,350 ¥ 90,114,296
Unallocated amounts [Member]      
Disclosure of operating segments [line items]      
Total assets ¥ 16,571,156 ¥ 15,643,613 ¥ 15,790,074