v3.25.3
Derivative Financial Instruments - Impact on Derivatives and Hedged Items on Consolidated Statement of Income (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]        
Amount of Gain
(Loss) on Derivative
Recognized in
Consolidated
Statement of Income $ (18) $ (308) $ (162) $ (296)
Amount of Gain
(Loss) on Hedged
Item Recognized in
Consolidated
Statement of Income 18 309 162 297
Net unrealized losses on AFS investment securities designated in fair value hedges 31 436 351 404
Net interest income | Interest rate contracts | Available-for-sale securities        
Derivative Instruments and Hedging Activities Disclosures [Line Items]        
Amount of Gain
(Loss) on Derivative
Recognized in
Consolidated
Statement of Income (37) (521) (425) (478)
Amount of Gain
(Loss) on Hedged
Item Recognized in
Consolidated
Statement of Income 37 522 425 479
Net interest income | Interest rate contracts | Long-term debt        
Derivative Instruments and Hedging Activities Disclosures [Line Items]        
Amount of Gain
(Loss) on Derivative
Recognized in
Consolidated
Statement of Income 31 195 276 159
Amount of Gain
(Loss) on Hedged
Item Recognized in
Consolidated
Statement of Income (31) (195) (276) (159)
Other fee revenue | Foreign exchange contracts | Available-for-sale securities        
Derivative Instruments and Hedging Activities Disclosures [Line Items]        
Amount of Gain
(Loss) on Derivative
Recognized in
Consolidated
Statement of Income (12) 18 (13) 23
Amount of Gain
(Loss) on Hedged
Item Recognized in
Consolidated
Statement of Income $ 12 $ (18) $ 13 $ (23)