Fair Value (Recurring Fair Value Measurements) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	$ 332,941	$ 354,809
Equity securities	1,063	1,079
Unit-linked and FVO Securities (2)	12,975	13,319
Short-term investments (3)	4,781	3,904
Residential mortgage loans — FVO	83,015	83,919
Derivative assets	9,962	11,866
Separate account assets	196,200	199,970
Liabilities [Abstract]
Derivative liabilities	4,829	4,229
Embedded derivatives within liability host contracts	555	1,196
Separate account liabilities	196,200	199,970
Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans — FVO	149	165
Recurring
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	332,941	354,809
Equity securities	1,063	1,079
Unit-linked and FVO Securities (2)	12,975	13,319
Short-term investments (3)	4,207	3,373
Other investments	995	885
Derivative assets	9,962	11,866
Embedded derivatives within asset host contracts	47	55
Separate account assets	196,200	199,970
Total assets (7)	558,539	585,521
Liabilities [Abstract]
Derivative liabilities	4,829	4,229
Embedded derivatives within liability host contracts	555	1,196
Total liabilities	5,417	5,451
Recurring \| Interest rate contracts
Assets [Abstract]
Derivative assets	6,487	8,329
Liabilities [Abstract]
Derivative liabilities	657	238
Recurring \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	2,306	2,466
Liabilities [Abstract]
Derivative liabilities	3,490	3,101
Recurring \| Credit contracts
Assets [Abstract]
Derivative assets	194	205
Liabilities [Abstract]
Derivative liabilities	118	121
Recurring \| Equity market contracts
Assets [Abstract]
Derivative assets	975	866
Liabilities [Abstract]
Derivative liabilities	564	769
Recurring \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	33	26
Recurring \| Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans — FVO	149	165
Recurring \| U.S. corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	88,002	93,416
Recurring \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	67,137	71,699
Recurring \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	65,883	69,408
Recurring \| U.S. government and agency
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	41,402	47,100
Recurring \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	29,302	30,435
Recurring \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	16,217	17,119
Recurring \| Municipals
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	13,212	13,722
Recurring \| CMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	11,786	11,910
Recurring \| Level 1
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	21,003	23,180
Equity securities	649	636
Unit-linked and FVO Securities (2)	10,325	10,559
Short-term investments (3)	2,652	2,762
Other investments	82	83
Derivative assets	17	17
Embedded derivatives within asset host contracts	0	0
Separate account assets	90,042	91,850
Total assets (7)	124,770	129,087
Liabilities [Abstract]
Derivative liabilities	19	40
Embedded derivatives within liability host contracts	0	0
Total liabilities	27	52
Recurring \| Level 1 \| Interest rate contracts
Assets [Abstract]
Derivative assets	7	0
Liabilities [Abstract]
Derivative liabilities	0	2
Recurring \| Level 1 \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	0	3
Liabilities [Abstract]
Derivative liabilities	7	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	10	14
Liabilities [Abstract]
Derivative liabilities	12	38
Recurring \| Level 1 \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	8	12
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	23,180
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	20,896	0
Recurring \| Level 1 \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	107	0
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	282,875	302,122
Equity securities	260	293
Unit-linked and FVO Securities (2)	1,838	2,059
Short-term investments (3)	1,453	568
Other investments	257	229
Derivative assets	9,728	11,137
Embedded derivatives within asset host contracts	0	0
Separate account assets	105,010	107,035
Total assets (7)	401,421	423,443
Liabilities [Abstract]
Derivative liabilities	4,431	4,071
Embedded derivatives within liability host contracts	0	0
Total liabilities	4,441	4,079
Recurring \| Level 2 \| Interest rate contracts
Assets [Abstract]
Derivative assets	6,455	7,840
Liabilities [Abstract]
Derivative liabilities	327	168
Recurring \| Level 2 \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	2,156	2,287
Liabilities [Abstract]
Derivative liabilities	3,448	3,063
Recurring \| Level 2 \| Credit contracts
Assets [Abstract]
Derivative assets	170	180
Liabilities [Abstract]
Derivative liabilities	117	121
Recurring \| Level 2 \| Equity market contracts
Assets [Abstract]
Derivative assets	947	830
Liabilities [Abstract]
Derivative liabilities	539	719
Recurring \| Level 2 \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	10	8
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	78,190	83,214
Recurring \| Level 2 \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	67,005	55,509
Recurring \| Level 2 \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	52,276	23,920
Recurring \| Level 2 \| U.S. government and agency
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	20,506	71,582
Recurring \| Level 2 \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	26,009	27,133
Recurring \| Level 2 \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	14,603	15,734
Recurring \| Level 2 \| Municipals
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	13,207	13,722
Recurring \| Level 2 \| CMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	11,079	11,308
Recurring \| Level 3
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	29,063	29,507
Equity securities	154	150
Unit-linked and FVO Securities (2)	812	701
Short-term investments (3)	102	43
Other investments	656	573
Derivative assets	217	712
Embedded derivatives within asset host contracts	47	55
Separate account assets	1,148	1,085
Total assets (7)	32,348	32,991
Liabilities [Abstract]
Derivative liabilities	379	118
Embedded derivatives within liability host contracts	555	1,196
Total liabilities	949	1,320
Recurring \| Level 3 \| Interest rate contracts
Assets [Abstract]
Derivative assets	25	489
Liabilities [Abstract]
Derivative liabilities	330	68
Recurring \| Level 3 \| Foreign currency exchange rate contracts
Assets [Abstract]
Derivative assets	150	176
Liabilities [Abstract]
Derivative liabilities	35	38
Recurring \| Level 3 \| Credit contracts
Assets [Abstract]
Derivative assets	24	25
Liabilities [Abstract]
Derivative liabilities	1	0
Recurring \| Level 3 \| Equity market contracts
Assets [Abstract]
Derivative assets	18	22
Liabilities [Abstract]
Derivative liabilities	13	12
Recurring \| Level 3 \| Derivative Liabilities Within Separate Accounts
Liabilities [Abstract]
Separate account liabilities	15	6
Recurring \| Level 3 \| Residential mortgage loans - FVO
Assets [Abstract]
Residential mortgage loans — FVO	149	165
Recurring \| Level 3 \| U.S. corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	9,812	10,202
Recurring \| Level 3 \| Foreign government
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	132	13,899
Recurring \| Level 3 \| Foreign corporate
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	13,607	0
Recurring \| Level 3 \| U.S. government and agency
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	0	117
Recurring \| Level 3 \| RMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	3,186	3,302
Recurring \| Level 3 \| ABS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	1,614	1,385
Recurring \| Level 3 \| Municipals
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	5	0
Recurring \| Level 3 \| CMBS
Assets [Abstract]
Estimated Fair Value of Fixed Maturity Securities AFS	707	602
Other limited partnership interests \| Recurring
Assets [Abstract]
Investments, Fair Value Disclosure	$ 77	$ 75

Fair value of investments in fund assets.

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