Derivatives (Credit Risk on Freestanding Derivatives) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	$ 3,172	$ 2,447
Derivative, Collateral, Right to Reclaim Cash	99	98
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	8,534	8,918
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	7,071	6,307
Derivative Asset, Fair Value, Amount Offset Against Collateral	84	183
Derivative Liability, Fair Value, Amount Offset Against Collateral	14	19
Derivative assets	8,291	8,737
Derivative liabilities	6,985	6,298
Derivative, Collateral, Obligation to Return Cash	35	163
Customer Securities for which Entity has Right to Sell or Repledge, Fair Value of Securities Sold or Repledged	0
Collateral Amount Not Provided Due to Downgrade Threshold	15
Exchange Traded [Member]
Credit Derivatives [Line Items]
Derivative, Collateral, Right to Reclaim Securities	154	137
Gross estimated fair value of derivative assets	6	11
Gross estimated fair value of derivative liabilities	7	16
Derivative Asset, Subject to Master Netting Arrangement, Deduction of Financial Instrument Not Offset	(1)	(1)
Derivative Liability, Subject to Master Netting Arrangement, Deduction of Financial Instrument Not Offset	(1)	(1)
Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash, Offset Against Derivative Asset	0	0
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Offset	(6)	(5)
Derivative Asset, Collateral, Obligation to Return Securities, Offset	0	0
Derivative Liability, Collateral, Right to Reclaim Securities, Offset	0	(10)
Over the Counter [Member]
Credit Derivatives [Line Items]
Derivative, Collateral, Right to Reclaim Securities	1,400	1,500
Gross estimated fair value of derivative assets	8,347	8,749
Gross estimated fair value of derivative liabilities	6,834	6,014
Derivative Asset, Subject to Master Netting Arrangement, Deduction of Financial Instrument Not Offset	(3,661)	(3,568)
Derivative Liability, Subject to Master Netting Arrangement, Deduction of Financial Instrument Not Offset	(3,661)	(3,568)
Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash, Offset Against Derivative Asset	(3,195)	(3,448)
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Offset	0	0
Derivative Asset, Collateral, Obligation to Return Securities, Offset	(1,416)	(1,563)
Derivative Liability, Collateral, Right to Reclaim Securities, Offset	(3,160)	(2,427)
Derivative, Collateral, Obligation to Return Securities	324	298
Exchange Cleared [Member]
Credit Derivatives [Line Items]
Derivative, Collateral, Right to Reclaim Securities	901	945
Gross estimated fair value of derivative assets	181	158
Gross estimated fair value of derivative liabilities	230	277
Derivative Asset, Subject to Master Netting Arrangement, Deduction of Financial Instrument Not Offset	(1)	(5)
Derivative Liability, Subject to Master Netting Arrangement, Deduction of Financial Instrument Not Offset	(1)	(5)
Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash, Offset Against Derivative Asset	(176)	(150)
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Offset	(213)	(239)
Derivative Asset, Collateral, Obligation to Return Securities, Offset	0	0
Derivative Liability, Collateral, Right to Reclaim Securities, Offset	(15)	(33)
Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	3,870	3,017
Accrued Liabilities [Member]
Credit Derivatives [Line Items]
Derivative assets	243	181
Derivative liabilities	86	9
Derivatives Subject to Credit- Contingent Provisions
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	3,079	2,443
Derivatives Subject to Credit- Contingent Provisions | Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	3,774	3,011
Derivatives Not Subject to Credit- Contingent Provisions
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	93	4
Derivatives Not Subject to Credit- Contingent Provisions | Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	$ 96	$ 6