XML 119 R116.htm IDEA: XBRL DOCUMENT v3.25.3
Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Liability For Future Policy Benefit, Weighted Average Duration (Detail)
Sep. 30, 2025
Mar. 31, 2025
Yen-denominated insurance (First Sector)    
Liability for Future Policy Benefit, Activity [Line Items]    
Liability for future policy benefit weighted average duration 34 years 6 months 35 years 1 month 6 days
Yen-denominated insurance (Third Sector)    
Liability for Future Policy Benefit, Activity [Line Items]    
Liability for future policy benefit weighted average duration 31 years 7 months 6 days 32 years 6 months
Foreign currency denominated insurance    
Liability for Future Policy Benefit, Activity [Line Items]    
Liability for future policy benefit weighted average duration 31 years 10 months 24 days 33 years 6 months