v3.25.4
Borrowings - Narrative (Details) - USD ($)
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Line of Credit Facility [Line Items]    
Other short-term borrowings $ 6,913,000,000 $ 5,999,000,000
Weighted-average interest rate of short-term borrowings 4.09% 5.21%
Capacity of allowable commercial paper note issuance $ 5,000,000,000.0  
Commercial paper outstanding 1,900,000,000 $ 0
Secured Uncommitted Lines Of Credit    
Line of Credit Facility [Line Items]    
Other short-term borrowings 3,800,000,000 500,000,000
Repurchase agreements    
Line of Credit Facility [Line Items]    
Other short-term borrowings 1,300,000,000 5,500,000,000
Federal Reserve Bank Advances    
Line of Credit Facility [Line Items]    
Other short-term borrowings 0 0
Total borrowing capacity $ 29,300,000,000 30,500,000,000
Commercial paper    
Line of Credit Facility [Line Items]    
Maturity term 270 days  
Discount $ 32,000,000  
Secured Debt | Federal Home Loan Bank Advances    
Line of Credit Facility [Line Items]    
Borrowings outstanding $ 1,900,000,000 $ 16,700,000,000
Weighted average interest rate 3.90% 5.11%
Line of credit facility, current borrowing capacity $ 74,200,000,000 $ 59,800,000,000
Line of Credit | Uncommitted Lines Of Credit With External Banks    
Line of Credit Facility [Line Items]    
Other short-term borrowings 0 0
Total borrowing capacity 1,900,000,000  
Line of Credit | Secured Uncommitted Lines Of Credit    
Line of Credit Facility [Line Items]    
Other short-term borrowings $ 3,800,000,000 $ 500,000,000