Fair Value (Recurring Fair Value Measurements) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Assets [Abstract]
Fixed maturity securities, estimated fair value	$ 80,474	$ 80,991
Equity securities	86	102
Short-term investments	1,347	1,169
Derivative assets	3,845	3,714
Market risk benefit assets	839	656
Separate account assets	90,332	88,271
Liabilities [Abstract]
Market risk benefit liabilities	8,964	10,323
Derivative liabilities	5,373	5,088
Recurring
Assets [Abstract]
Fixed maturity securities, estimated fair value	80,474	80,991
Equity securities	86	102
Short-term investments	1,347	1,169
Derivative assets	3,845	3,714
Embedded derivatives on index-linked annuities	22	0
Market risk benefit assets	839	656
Separate account assets	90,332	88,271
Total assets	176,945	174,903
Liabilities [Abstract]
Market risk benefit liabilities	8,964	10,323
Derivative liabilities	5,373	5,088
Embedded derivatives on index-linked annuities (2)	9,963	8,186
Total liabilities	24,300	23,597
Recurring \| Interest rate
Assets [Abstract]
Derivative assets	259	245
Liabilities [Abstract]
Derivative liabilities	2,738	2,209
Recurring \| Foreign currency exchange rate
Assets [Abstract]
Derivative assets	484	449
Liabilities [Abstract]
Derivative liabilities	31	55
Recurring \| Credit
Assets [Abstract]
Derivative assets	29	27
Liabilities [Abstract]
Derivative liabilities	1	0
Recurring \| Equity market
Assets [Abstract]
Derivative assets	3,073	2,993
Liabilities [Abstract]
Derivative liabilities	2,603	2,824
Recurring \| U.S. corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	35,937	35,755
Recurring \| Foreign corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	11,759	11,665
Recurring \| U.S. government and agency
Assets [Abstract]
Fixed maturity securities, estimated fair value	7,633	8,419
Recurring \| RMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	7,462	7,430
Recurring \| CMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	6,454	6,410
Recurring \| ABS
Assets [Abstract]
Fixed maturity securities, estimated fair value	6,465	6,406
Recurring \| State and political subdivision
Assets [Abstract]
Fixed maturity securities, estimated fair value	3,761	3,874
Recurring \| Foreign government
Assets [Abstract]
Fixed maturity securities, estimated fair value	1,003	1,032
Recurring \| Level 1
Assets [Abstract]
Fixed maturity securities, estimated fair value	3,167	3,786
Equity securities	51	55
Short-term investments	709	614
Derivative assets	0	0
Embedded derivatives on index-linked annuities	0	0
Market risk benefit assets	0	0
Separate account assets	14	20
Total assets	3,941	4,475
Liabilities [Abstract]
Market risk benefit liabilities	0	0
Derivative liabilities	0	0
Embedded derivatives on index-linked annuities (2)	0	0
Total liabilities	0	0
Recurring \| Level 1 \| Interest rate
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 1 \| Foreign currency exchange rate
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 1 \| Credit
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 1 \| Equity market
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 1 \| U.S. corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	0	0
Recurring \| Level 1 \| Foreign corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	0	0
Recurring \| Level 1 \| U.S. government and agency
Assets [Abstract]
Fixed maturity securities, estimated fair value	3,167	3,786
Recurring \| Level 1 \| RMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	0	0
Recurring \| Level 1 \| CMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	0	0
Recurring \| Level 1 \| ABS
Assets [Abstract]
Fixed maturity securities, estimated fair value	0	0
Recurring \| Level 1 \| State and political subdivision
Assets [Abstract]
Fixed maturity securities, estimated fair value	0	0
Recurring \| Level 1 \| Foreign government
Assets [Abstract]
Fixed maturity securities, estimated fair value	0	0
Recurring \| Level 2
Assets [Abstract]
Fixed maturity securities, estimated fair value	75,537	75,469
Equity securities	10	22
Short-term investments	638	555
Derivative assets	3,834	3,696
Embedded derivatives on index-linked annuities	0	0
Market risk benefit assets	0	0
Separate account assets	90,318	88,251
Total assets	170,337	167,993
Liabilities [Abstract]
Market risk benefit liabilities	0	0
Derivative liabilities	5,373	5,088
Embedded derivatives on index-linked annuities (2)	0	0
Total liabilities	5,373	5,088
Recurring \| Level 2 \| Interest rate
Assets [Abstract]
Derivative assets	259	245
Liabilities [Abstract]
Derivative liabilities	2,738	2,209
Recurring \| Level 2 \| Foreign currency exchange rate
Assets [Abstract]
Derivative assets	478	437
Liabilities [Abstract]
Derivative liabilities	31	55
Recurring \| Level 2 \| Credit
Assets [Abstract]
Derivative assets	24	21
Liabilities [Abstract]
Derivative liabilities	1	0
Recurring \| Level 2 \| Equity market
Assets [Abstract]
Derivative assets	3,073	2,993
Liabilities [Abstract]
Derivative liabilities	2,603	2,824
Recurring \| Level 2 \| U.S. corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	34,995	34,760
Recurring \| Level 2 \| Foreign corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	11,434	11,340
Recurring \| Level 2 \| U.S. government and agency
Assets [Abstract]
Fixed maturity securities, estimated fair value	4,466	4,633
Recurring \| Level 2 \| RMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	7,442	7,415
Recurring \| Level 2 \| CMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	6,411	6,371
Recurring \| Level 2 \| ABS
Assets [Abstract]
Fixed maturity securities, estimated fair value	6,046	6,080
Recurring \| Level 2 \| State and political subdivision
Assets [Abstract]
Fixed maturity securities, estimated fair value	3,761	3,874
Recurring \| Level 2 \| Foreign government
Assets [Abstract]
Fixed maturity securities, estimated fair value	982	996
Recurring \| Level 3
Assets [Abstract]
Fixed maturity securities, estimated fair value	1,770	1,736
Equity securities	25	25
Short-term investments	0	0
Derivative assets	11	18
Embedded derivatives on index-linked annuities	22	0
Market risk benefit assets	839	656
Separate account assets	0	0
Total assets	2,667	2,435
Liabilities [Abstract]
Market risk benefit liabilities	8,964	10,323
Derivative liabilities	0	0
Embedded derivatives on index-linked annuities (2)	9,963	8,186
Total liabilities	18,927	18,509
Recurring \| Level 3 \| Interest rate
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 3 \| Foreign currency exchange rate
Assets [Abstract]
Derivative assets	6	12
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 3 \| Credit
Assets [Abstract]
Derivative assets	5	6
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 3 \| Equity market
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 3 \| U.S. corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	942	995
Recurring \| Level 3 \| Foreign corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	325	325
Recurring \| Level 3 \| U.S. government and agency
Assets [Abstract]
Fixed maturity securities, estimated fair value	0	0
Recurring \| Level 3 \| RMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	20	15
Recurring \| Level 3 \| CMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	43	39
Recurring \| Level 3 \| ABS
Assets [Abstract]
Fixed maturity securities, estimated fair value	419	326
Recurring \| Level 3 \| State and political subdivision
Assets [Abstract]
Fixed maturity securities, estimated fair value	0	0
Recurring \| Level 3 \| Foreign government
Assets [Abstract]
Fixed maturity securities, estimated fair value	$ 21	$ 36

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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