Fair Value (Recurring Fair Value Measurements) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	$ 340,005	$ 327,820
Equity securities	1,105	1,342
Unit-linked and FVO Securities (1)	11,911	13,102
Short-term investments	5,345	3,850
Residential mortgage loans - FVO	82,890	80,529
Derivative assets	15,871	10,084
Separate account assets	187,343	188,445
Liabilities [Abstract]
Derivative liabilities	4,001	3,737
Embedded derivatives within liability host contracts	1,994	802
Separate account liabilities	187,343	188,445
Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans - FVO	175	188
Recurring
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	340,005	327,820
Equity securities	1,105	1,342
Unit-linked and FVO Securities (1)	11,911	13,102
Short-term investments	4,862	3,182
Other investments	735	689
Derivative assets	15,871	10,084
Embedded derivatives within asset host contracts	69	60
Separate account assets	187,343	188,445
Total assets (6)	562,076	544,912
Liabilities [Abstract]
Derivative liabilities	4,001	3,737
Embedded derivatives within liability host contracts	1,994	802
Total liabilities	6,034	4,561
Recurring \| Interest rate contracts
Assets [Abstract]
Derivative assets	10,213	6,707
Liabilities [Abstract]
Derivative liabilities	202	418
Recurring \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	4,502	2,378
Liabilities [Abstract]
Derivative liabilities	3,090	2,442
Recurring \| Credit contracts
Assets [Abstract]
Derivative assets	145	276
Liabilities [Abstract]
Derivative liabilities	118	103
Recurring \| Equity market contracts
Assets [Abstract]
Derivative assets	1,011	723
Liabilities [Abstract]
Derivative liabilities	591	774
Recurring \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	39	22
Recurring \| Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans - FVO	175	188
Recurring \| U.S. corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	90,112	87,753
Recurring \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	65,706	67,229
Recurring \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	62,817	64,165
Recurring \| U.S. government and agency
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	47,287	42,084
Recurring \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	31,875	28,547
Recurring \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	16,324	14,542
Recurring \| Municipals
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	14,611	13,053
Recurring \| CMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	11,273	10,447
Recurring \| Level 1
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	22,551	21,061
Equity securities	556	794
Unit-linked and FVO Securities (1)	9,406	10,598
Short-term investments	3,019	2,042
Other investments	70	74
Derivative assets	5	15
Embedded derivatives within asset host contracts	0	0
Separate account assets	84,717	86,790
Total assets (6)	120,324	121,374
Liabilities [Abstract]
Derivative liabilities	51	11
Embedded derivatives within liability host contracts	0	0
Total liabilities	52	12
Recurring \| Level 1 \| Interest rate contracts
Assets [Abstract]
Derivative assets	2	2
Liabilities [Abstract]
Derivative liabilities	0	3
Recurring \| Level 1 \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	0	7
Liabilities [Abstract]
Derivative liabilities	6	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	3	6
Liabilities [Abstract]
Derivative liabilities	45	8
Recurring \| Level 1 \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	1	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	22,074	21,058
Recurring \| Level 1 \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	477	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	291,288	287,948
Equity securities	176	118
Unit-linked and FVO Securities (1)	1,916	1,879
Short-term investments	1,836	1,108
Other investments	174	160
Derivative assets	14,815	9,882
Embedded derivatives within asset host contracts	0	0
Separate account assets	101,559	100,668
Total assets (6)	411,764	401,763
Liabilities [Abstract]
Derivative liabilities	3,697	3,393
Embedded derivatives within liability host contracts	0	0
Total liabilities	3,724	3,407
Recurring \| Level 2 \| Interest rate contracts
Assets [Abstract]
Derivative assets	9,258	6,616
Liabilities [Abstract]
Derivative liabilities	131	220
Recurring \| Level 2 \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	4,474	2,336
Liabilities [Abstract]
Derivative liabilities	2,918	2,324
Recurring \| Level 2 \| Credit contracts
Assets [Abstract]
Derivative assets	126	244
Liabilities [Abstract]
Derivative liabilities	114	102
Recurring \| Level 2 \| Equity market contracts
Assets [Abstract]
Derivative assets	957	686
Liabilities [Abstract]
Derivative liabilities	534	747
Recurring \| Level 2 \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	27	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	80,921	81,501
Recurring \| Level 2 \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	65,649	67,112
Recurring \| Level 2 \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	51,276	56,188
Recurring \| Level 2 \| U.S. government and agency
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	25,213	21,026
Recurring \| Level 2 \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	27,730	25,682
Recurring \| Level 2 \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	15,394	13,326
Recurring \| Level 2 \| Municipals
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	14,611	13,046
Recurring \| Level 2 \| CMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	10,494	10,067
Recurring \| Level 3
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	26,166	18,811
Equity securities	373	430
Unit-linked and FVO Securities (1)	589	625
Short-term investments	7	32
Other investments	491	455
Derivative assets	1,051	187
Embedded derivatives within asset host contracts	69	60
Separate account assets	1,067	987
Total assets (6)	29,988	21,775
Liabilities [Abstract]
Derivative liabilities	253	333
Embedded derivatives within liability host contracts	1,994	802
Total liabilities	2,258	1,142
Recurring \| Level 3 \| Interest rate contracts
Assets [Abstract]
Derivative assets	953	89
Liabilities [Abstract]
Derivative liabilities	71	195
Recurring \| Level 3 \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	28	35
Liabilities [Abstract]
Derivative liabilities	166	118
Recurring \| Level 3 \| Credit contracts
Assets [Abstract]
Derivative assets	19	32
Liabilities [Abstract]
Derivative liabilities	4	1
Recurring \| Level 3 \| Equity market contracts
Assets [Abstract]
Derivative assets	51	31
Liabilities [Abstract]
Derivative liabilities	12	19
Recurring \| Level 3 \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	11	7
Recurring \| Level 3 \| Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans - FVO	175	188
Recurring \| Level 3 \| U.S. corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	9,191	6,252
Recurring \| Level 3 \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	57	117
Recurring \| Level 3 \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	11,541	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	3,668	2,862
Recurring \| Level 3 \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	930	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	779	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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