v3.26.1
Transactions Involving Related Parties - Narrative (Detail) - USD ($)
$ in Millions
1 Months Ended 3 Months Ended
Jul. 31, 2026
Jul. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
HMC | AHFC        
Related Party Transaction [Line Items]        
Honda Motor Company required ownership interest (percentage)     80.00%  
HMC | HCFI        
Related Party Transaction [Line Items]        
Honda Motor Company required ownership interest (percentage)     80.00%  
AHM        
Related Party Transaction [Line Items]        
Dividends declared     $ 484 $ 562
AHFC | HCFI        
Related Party Transaction [Line Items]        
Dividends declared   $ 74    
AHFC | HCFI | Subsequent Event        
Related Party Transaction [Line Items]        
Dividends declared $ 111      
HCI | HCFI        
Related Party Transaction [Line Items]        
Dividends declared   $ 68    
HCI | HCFI | Subsequent Event        
Related Party Transaction [Line Items]        
Dividends declared $ 101