Commitments, Contingencies, And Guarantees (Narrative) (Detail) € in Millions, $ in Millions	9 Months Ended
	Sep. 30, 2025 USD ($)	Sep. 30, 2025 EUR (€)	Dec. 31, 2024 USD ($)
Financial Instruments Owned and Pledged as Collateral [Line Items]
Repurchase agreements	$ 3,360		$ 2,731
Carrying value of limited partnerships and partially-owned investment companies included in other investments	16,400		14,500
Unrecognized tax benefits	76
Operating Lease, Right-of-Use Asset	1,044		824
Operating Lease, Liability	$ 1,183		$ 942
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other liabilities	Other liabilities	Other liabilities
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets (includes VIE balances of $95 and $26)	Other assets (includes VIE balances of $95 and $26)	Other assets (includes VIE balances of $95 and $26)
Derivative Liability, Subject to Master Netting Arrangement, after Offset	$ 84		$ 199
Private Equity Funds [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Funding commitments relating to limited partnerships and partially-owned investment companies	6,400		6,400
Fixed Maturities [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Funding commitments relating to limited partnerships and partially-owned investment companies	1,400		$ 1,300
Net Investment Hedging | Designated as Hedging Instrument
Financial Instruments Owned and Pledged as Collateral [Line Items]
Notional Amount of Nonderivative Instruments	1,200
Fair Value Hedging
Financial Instruments Owned and Pledged as Collateral [Line Items]
Hedged Liability, Fair Value Hedge	$ 2,000	€ 1,700