Fair Value of Financial Instruments - Components of the Transfers In and Out of Level 3 (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	$ 92	$ 280	$ 352
Transfers Out of Level 3	(743)	(608)	(3,400)
Total	(651)	(328)	(3,048)
Corporate bonds
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	22	195	296
Transfers Out of Level 3	(153)	(206)	(2,968)
Total	(131)	(11)	(2,672)
State and municipal bonds
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	0		36
Transfers Out of Level 3	(5)		0
Total	(5)		36
Foreign government bonds
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3			0
Transfers Out of Level 3			(5)
Total			(5)
RMBS
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	0	12	0
Transfers Out of Level 3	(5)	(5)	(25)
Total	(5)	7	(25)
CMBS
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	0	12	0
Transfers Out of Level 3	(28)	0	(17)
Total	(28)	12	(17)
ABS
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	50	2	16
Transfers Out of Level 3	(497)	(377)	(332)
Total	(447)	(375)	(316)
Hybrid and redeemable preferred securities
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	10	16	0
Transfers Out of Level 3	0	(13)	(4)
Total	10	3	(4)
Trading securities
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3		6	4
Transfers Out of Level 3		(7)	(19)
Total		(1)	(15)
Equity securities
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	0	6	0
Transfers Out of Level 3	(4)	0	(15)
Total	(4)	6	(15)
Other investments
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	10
Transfers Out of Level 3	0
Total	10
Derivative liabilities
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	0	31	0
Transfers Out of Level 3	(51)	0	(15)
Total	$ (51)	$ 31	$ (15)