v3.26.1
Derivative Financial Instruments - Notional Amounts and Fair Values for All Derivative Instruments Included in the Condensed Consolidated Balance Sheets (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Derivatives, Fair Value    
Derivative Assets $ 3,330 $ 1,868
Derivative Liabilities 3,501 2,034
Amount of variation margin payment applied to derivative asset contracts 386 270
Amount of variation margin payment applied to derivative liability contracts 489 415
Designated as Hedging Instrument    
Derivatives, Fair Value    
Derivative Assets 2 8
Derivative Liabilities 14 0
Designated as Hedging Instrument | Fair Value Hedging    
Derivatives, Fair Value    
Derivative Assets 1 1
Derivative Liabilities 12 0
Designated as Hedging Instrument | Fair Value Hedging | Interest rate swap | Long-term debt    
Derivatives, Fair Value    
Notional Amount 6,105 4,205
Derivative Assets 1 1
Derivative Liabilities 12 0
Designated as Hedging Instrument | Cash Flow Hedging    
Derivatives, Fair Value    
Derivative Assets 1 7
Derivative Liabilities 2 0
Designated as Hedging Instrument | Cash Flow Hedging | Interest rate swap | Commercial and industrial    
Derivatives, Fair Value    
Notional Amount 6,850 6,850
Derivative Assets 0 5
Derivative Liabilities 2 0
Designated as Hedging Instrument | Cash Flow Hedging | Interest rate swap | Commercial mortgage and commercial construction    
Derivatives, Fair Value    
Notional Amount 4,000  
Derivative Assets 1  
Derivative Liabilities 0  
Designated as Hedging Instrument | Cash Flow Hedging | Forward starting interest rate swap | Commercial mortgage and commercial construction    
Derivatives, Fair Value    
Notional Amount   4,000
Derivative Assets   2
Derivative Liabilities   0
Not Designated as Hedging Instrument    
Derivatives, Fair Value    
Derivative Assets 3,328 1,860
Derivative Liabilities 3,487 2,034
Not Designated as Hedging Instrument | Risk Management and Other Business Purposes    
Derivatives, Fair Value    
Derivative Assets 28 7
Derivative Liabilities 93 130
Not Designated as Hedging Instrument | Risk Management and Other Business Purposes | Interest rate contracts related to MSR portfolio    
Derivatives, Fair Value    
Notional Amount 4,105 4,275
Derivative Assets 7 6
Derivative Liabilities 9 1
Not Designated as Hedging Instrument | Risk Management and Other Business Purposes | Forward contracts related to residential mortgage loans measured at fair value | Loans Measured At Fair Value    
Derivatives, Fair Value    
Notional Amount 1,382 1,072
Derivative Assets 11 1
Derivative Liabilities 2 3
Not Designated as Hedging Instrument | Risk Management and Other Business Purposes | Swap    
Derivatives, Fair Value    
Notional Amount 2,480 2,678
Derivative Assets 0 0
Derivative Liabilities 82 124
Not Designated as Hedging Instrument | Risk Management and Other Business Purposes | Foreign exchange contracts    
Derivatives, Fair Value    
Notional Amount 500 150
Derivative Assets 10 0
Derivative Liabilities 0 2
Not Designated as Hedging Instrument | Risk Management and Other Business Purposes | Other    
Derivatives, Fair Value    
Notional Amount 80 82
Derivative Assets 0 0
Derivative Liabilities 0 0
Not Designated as Hedging Instrument | Customer Accommodation    
Derivatives, Fair Value    
Derivative Assets 3,300 1,853
Derivative Liabilities 3,394 1,904
Not Designated as Hedging Instrument | Customer Accommodation | Foreign exchange contracts    
Derivatives, Fair Value    
Notional Amount 24,575 26,166
Derivative Assets 543 659
Derivative Liabilities 486 626
Not Designated as Hedging Instrument | Customer Accommodation | Interest rate contracts    
Derivatives, Fair Value    
Notional Amount 102,255 82,901
Derivative Assets 553 443
Derivative Liabilities 711 540
Amount of variation margin payment applied to derivative asset contracts 239 120
Amount of variation margin payment applied to derivative liability contracts 37 29
Not Designated as Hedging Instrument | Customer Accommodation | Interest rate lock commitments    
Derivatives, Fair Value    
Notional Amount 486 317
Derivative Assets 7 5
Derivative Liabilities 1 0
Not Designated as Hedging Instrument | Customer Accommodation | Commodity contracts    
Derivatives, Fair Value    
Notional Amount 35,186 16,945
Derivative Assets 2,197 746
Derivative Liabilities 2,196 738
Not Designated as Hedging Instrument | Customer Accommodation | TBA securities    
Derivatives, Fair Value    
Notional Amount 53 31
Derivative Assets 0 0
Derivative Liabilities $ 0 $ 0