v3.26.1
Derivatives and Hedging Activities (Derivatives in Statement of Condition) (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Derivatives, Fair Value [Line Items]    
Derivative, Notional Amount $ 212,776 $ 186,162
Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement 269 240
Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement 52 29
Derivative Asset, Subject to Master Netting Arrangement, Gross Liability and Collateral, Obligation to Return Cash, Offset (181) (160)
Derivative Liability, Subject to Master Netting Arrangement, Gross Asset and Collateral, Right to Reclaim Cash, Offset (45) (26)
Derivative assets, net 88 80
Derivative liabilities, net 7 3
Derivative Liability, Collateral, Right to Reclaim Cash, Offset 148 137
Derivative Asset, Collateral, Obligation to Return Cash, Offset 12 3
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]    
Derivatives, Fair Value [Line Items]    
Derivative, Notional Amount 201,901 162,769
Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement 265 237
Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement 52 29
Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Derivative, Notional Amount 10,875 23,393
Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement 4 3
Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement 0 0
Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]    
Derivatives, Fair Value [Line Items]    
Derivative, Notional Amount 10,617 23,176
Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement 4 3
Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement 0 0
Not Designated as Hedging Instrument [Member] | Forward Contracts [Member]    
Derivatives, Fair Value [Line Items]    
Derivative, Notional Amount 130 111
Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement 0 0
Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement 0 0
Not Designated as Hedging Instrument [Member] | interest rate caps and floors    
Derivatives, Fair Value [Line Items]    
Derivative, Notional Amount 1 0
Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement 0 0
Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement 0 0
Mortgages [Member] | Not Designated as Hedging Instrument [Member] | Forward Contracts [Member]    
Derivatives, Fair Value [Line Items]    
Derivative, Notional Amount 127 106
Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement 0 0
Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement $ 0 $ 0