Fair Value (Recurring Fair Value Measurements) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	$ 354,809	$ 327,820
Equity securities	1,079	1,342
Unit-linked and FVO Securities (1)	13,319	13,102
Short-term investments (3)	3,904	3,850
Residential mortgage loans — FVO	83,919	80,529
Derivative assets	11,866	10,084
Separate account assets	199,970	188,445
Liabilities [Abstract]
Derivative liabilities	4,229	3,737
Embedded derivatives within liability host contracts	1,196	802
Separate account liabilities	199,970	188,445
Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans — FVO	165	188
Recurring
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	354,809	327,820
Equity securities	1,079	1,342
Unit-linked and FVO Securities (1)	13,319	13,102
Short-term investments (3)	3,373	3,182
Other investments	885	689
Derivative assets	11,866	10,084
Embedded derivatives within asset host contracts	55	60
Separate account assets	199,970	188,445
Total assets (7)	585,521	544,912
Liabilities [Abstract]
Derivative liabilities	4,229	3,737
Embedded derivatives within liability host contracts	1,196	802
Total liabilities	5,451	4,561
Recurring \| Interest rate contracts
Assets [Abstract]
Derivative assets	8,329	6,707
Liabilities [Abstract]
Derivative liabilities	238	418
Recurring \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	2,466	2,378
Liabilities [Abstract]
Derivative liabilities	3,101	2,442
Recurring \| Credit contracts
Assets [Abstract]
Derivative assets	205	276
Liabilities [Abstract]
Derivative liabilities	121	103
Recurring \| Equity market contracts
Assets [Abstract]
Derivative assets	866	723
Liabilities [Abstract]
Derivative liabilities	769	774
Recurring \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	26	22
Recurring \| Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans — FVO	165	188
Recurring \| U.S. corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	93,416	87,753
Recurring \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	71,699	67,229
Recurring \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	69,408	64,165
Recurring \| U.S. government and agency
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	47,100	42,084
Recurring \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	30,435	28,547
Recurring \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	17,119	14,542
Recurring \| Municipals
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	13,722	13,053
Recurring \| CMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	11,910	10,447
Recurring \| Level 1
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	23,180	21,061
Equity securities	636	794
Unit-linked and FVO Securities (1)	10,559	10,598
Short-term investments (3)	2,762	2,042
Other investments	83	74
Derivative assets	17	15
Embedded derivatives within asset host contracts	0	0
Separate account assets	91,850	86,790
Total assets (7)	129,087	121,374
Liabilities [Abstract]
Derivative liabilities	40	11
Embedded derivatives within liability host contracts	0	0
Total liabilities	52	12
Recurring \| Level 1 \| Interest rate contracts
Assets [Abstract]
Derivative assets	0	2
Liabilities [Abstract]
Derivative liabilities	2	3
Recurring \| Level 1 \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	3	7
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 1 \| Credit contracts
Assets [Abstract]
Derivative assets	0	0
Liabilities [Abstract]
Derivative liabilities	0	0
Recurring \| Level 1 \| Equity market contracts
Assets [Abstract]
Derivative assets	14	6
Liabilities [Abstract]
Derivative liabilities	38	8
Recurring \| Level 1 \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	12	1
Recurring \| Level 1 \| Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans — FVO	0	0
Recurring \| Level 1 \| U.S. corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	0
Recurring \| Level 1 \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	0
Recurring \| Level 1 \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	0
Recurring \| Level 1 \| U.S. government and agency
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	23,180	21,058
Recurring \| Level 1 \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	3
Recurring \| Level 1 \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	0
Recurring \| Level 1 \| Municipals
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	0
Recurring \| Level 1 \| CMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	0
Recurring \| Level 2
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	302,122	287,948
Equity securities	293	118
Unit-linked and FVO Securities (1)	2,059	1,879
Short-term investments (3)	568	1,108
Other investments	229	160
Derivative assets	11,137	9,882
Embedded derivatives within asset host contracts	0	0
Separate account assets	107,035	100,668
Total assets (7)	423,443	401,763
Liabilities [Abstract]
Derivative liabilities	4,071	3,393
Embedded derivatives within liability host contracts	0	0
Total liabilities	4,079	3,407
Recurring \| Level 2 \| Interest rate contracts
Assets [Abstract]
Derivative assets	7,840	6,616
Liabilities [Abstract]
Derivative liabilities	168	220
Recurring \| Level 2 \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	2,287	2,336
Liabilities [Abstract]
Derivative liabilities	3,063	2,324
Recurring \| Level 2 \| Credit contracts
Assets [Abstract]
Derivative assets	180	244
Liabilities [Abstract]
Derivative liabilities	121	102
Recurring \| Level 2 \| Equity market contracts
Assets [Abstract]
Derivative assets	830	686
Liabilities [Abstract]
Derivative liabilities	719	747
Recurring \| Level 2 \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	8	14
Recurring \| Level 2 \| Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans — FVO	0	0
Recurring \| Level 2 \| U.S. corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	83,214	81,501
Recurring \| Level 2 \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	71,582	67,112
Recurring \| Level 2 \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	55,509	56,188
Recurring \| Level 2 \| U.S. government and agency
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	23,920	21,026
Recurring \| Level 2 \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	27,133	25,682
Recurring \| Level 2 \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	15,734	13,326
Recurring \| Level 2 \| Municipals
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	13,722	13,046
Recurring \| Level 2 \| CMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	11,308	10,067
Recurring \| Level 3
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	29,507	18,811
Equity securities	150	430
Unit-linked and FVO Securities (1)	701	625
Short-term investments (3)	43	32
Other investments	573	455
Derivative assets	712	187
Embedded derivatives within asset host contracts	55	60
Separate account assets	1,085	987
Total assets (7)	32,991	21,775
Liabilities [Abstract]
Derivative liabilities	118	333
Embedded derivatives within liability host contracts	1,196	802
Total liabilities	1,320	1,142
Recurring \| Level 3 \| Interest rate contracts
Assets [Abstract]
Derivative assets	489	89
Liabilities [Abstract]
Derivative liabilities	68	195
Recurring \| Level 3 \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	176	35
Liabilities [Abstract]
Derivative liabilities	38	118
Recurring \| Level 3 \| Credit contracts
Assets [Abstract]
Derivative assets	25	32
Liabilities [Abstract]
Derivative liabilities	0	1
Recurring \| Level 3 \| Equity market contracts
Assets [Abstract]
Derivative assets	22	31
Liabilities [Abstract]
Derivative liabilities	12	19
Recurring \| Level 3 \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	6	7
Recurring \| Level 3 \| Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans — FVO	165	188
Recurring \| Level 3 \| U.S. corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	10,202	6,252
Recurring \| Level 3 \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	117	117
Recurring \| Level 3 \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	13,899	7,977
Recurring \| Level 3 \| U.S. government and agency
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	0
Recurring \| Level 3 \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	3,302	2,862
Recurring \| Level 3 \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	1,385	1,216
Recurring \| Level 3 \| Municipals
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	7
Recurring \| Level 3 \| CMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	602	380
Other limited partnership interests \| Recurring
Assets [Abstract]
Investments, Fair Value Disclosure	$ 75	$ 95

Fair value of investments in fund assets.

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