v3.26.3
Commitments, Contingencies, And Guarantees (Balance Sheet Locations, Fair Values In Asset Or (Liability) Position, And Notional Values/Payment Provisions Of Derivative Instruments) (Detail) - USD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
Foreign currency forward contracts | Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset $ 123 $ 18
Fair Value, Liability (116) (230)
Derivative, Notional Amount 3,989 4,912
Options/Futures/Forward contracts on notes and bonds | Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 15 4
Fair Value, Liability (50) (12)
Derivative, Notional Amount 1,626 1,216
Convertible securities | Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Derivative, Notional Amount [1] 0 5
Derivative Asset, Not Subject to Master Netting Arrangement [1] 0 6
Derivative Liability, Not Subject to Master Netting Arrangement [1] 0 0
Investment And Embedded Derivative Instruments [Member] | Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 138 28
Fair Value, Liability (166) (242)
Derivative, Notional Amount 5,615 6,133
Futures contracts on equities | Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset [2] 0 3
Fair Value, Liability [2] (3) 0
Derivative, Notional Amount [2] 665 943
Other derivative instruments | Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 10 8
Fair Value, Liability 0 (4)
Derivative, Notional Amount 592 334
Other Derivative Instruments [Member] | Not Designated as Hedging Instrument [Member]    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 10 11
Fair Value, Liability (3) (4)
Derivative, Notional Amount 1,257 1,277
Currency Swap [Member] | Designated as Hedging Instrument    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 233 266
Fair Value, Liability (243) 232
Derivative, Notional Amount 5,786 5,041
Currency Swap [Member] | Fair Value Hedging | Designated as Hedging Instrument    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 167 198
Fair Value, Liability (6) 0
Derivative, Notional Amount 2,084 2,046
Currency Swap [Member] | Net Investment Hedging | Designated as Hedging Instrument    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 66 68
Fair Value, Liability (237) (232)
Derivative, Notional Amount $ 3,702 $ 2,995
[1] Includes fair value of embedded derivatives.
[2] Related to MRB book of business.