v3.25.4
Debt Securities (Narrative) (Details)
$ in Millions
3 Months Ended 12 Months Ended
Sep. 30, 2025
USD ($)
Jun. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
security
Dec. 31, 2024
USD ($)
security
Debt Securities, Available-for-sale [Line Items]        
Debt Securities Transferred from Available for Sale to Held to Maturity, Amortized Cost $ 2,000 $ 1,000    
Debt securities available for sale     $ 27,560 $ 26,224
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | security     1,058 1,564
Unrealized gains (losses) on securities available for sale:        
Debt Securities, Available-for-sale [Line Items]        
OCIDebtSecuritiesAvailableForSaleUnrealizedGainLossTransferredToHeldToMaturityArisingDuringBeforeTax $ 74 $ 153 $ 227 $ 754
Asset Pledged as Collateral        
Debt Securities, Available-for-sale [Line Items]        
Debt securities available for sale     $ 20,900 $ 20,900