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Fair Value (Recurring Fair Value Measurements) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Assets [Abstract]
Fixed maturity securities, estimated fair value	$ 77,685	$ 75,577
Equity securities	91	89
Short-term investments	1,386	1,081
Derivative assets: (1)	2,642	2,284
Market risk benefit assets	510	483
Separate account assets	87,440	84,965
Liabilities [Abstract]
Market risk benefit liabilities	10,729	10,389	$ 16,034
Derivative liabilities: (1)	3,253	3,920
Recurring
Assets [Abstract]
Fixed maturity securities, estimated fair value	77,685	75,577
Equity securities	91	89
Short-term investments	1,386	1,081
Derivative assets: (1)	2,642	2,284
Market risk benefit assets	510	483
Separate account assets	87,440	84,965
Total assets	169,754	164,479
Liabilities [Abstract]
Market risk benefit liabilities	10,729	10,389
Derivative liabilities: (1)	3,253	3,920
Embedded derivatives on index-linked annuities (2)	5,164	3,932
Total liabilities	19,146	18,241
Recurring \| Interest rate
Assets [Abstract]
Derivative assets: (1)	407	304
Liabilities [Abstract]
Derivative liabilities: (1)	1,995	2,802
Recurring \| Foreign currency exchange rate
Assets [Abstract]
Derivative assets: (1)	693	745
Liabilities [Abstract]
Derivative liabilities: (1)	9	18
Recurring \| Credit
Assets [Abstract]
Derivative assets: (1)	23	18
Liabilities [Abstract]
Derivative liabilities: (1)	1	2
Recurring \| Equity market
Assets [Abstract]
Derivative assets: (1)	1,519	1,217
Liabilities [Abstract]
Derivative liabilities: (1)	1,248	1,098
Recurring \| U.S. corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	33,612	32,607
Recurring \| Foreign corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	10,883	10,576
Recurring \| U.S. government and agency
Assets [Abstract]
Fixed maturity securities, estimated fair value	8,287	8,016
Recurring \| RMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	7,590	7,528
Recurring \| CMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	6,674	6,611
Recurring \| ABS
Assets [Abstract]
Fixed maturity securities, estimated fair value	5,596	5,359
Recurring \| State and political subdivision
Assets [Abstract]
Fixed maturity securities, estimated fair value	3,949	3,799
Recurring \| Foreign Government
Assets [Abstract]
Fixed maturity securities, estimated fair value	1,094	1,081
Recurring \| Level 1
Assets [Abstract]
Fixed maturity securities, estimated fair value	3,613	3,566
Equity securities	41	35
Short-term investments	911	722
Derivative assets: (1)	0	0
Market risk benefit assets	0	0
Separate account assets	20	29
Total assets	4,585	4,352
Liabilities [Abstract]
Market risk benefit liabilities	0	0
Derivative liabilities: (1)	0	0
Embedded derivatives on index-linked annuities (2)	0	0
Total liabilities	0	0
Recurring \| Level 1 \| Interest rate
Assets [Abstract]
Derivative assets: (1)	0	0
Liabilities [Abstract]
Derivative liabilities: (1)	0	0
Recurring \| Level 1 \| Foreign currency exchange rate
Assets [Abstract]
Derivative assets: (1)	0	0
Liabilities [Abstract]
Derivative liabilities: (1)	0	0
Recurring \| Level 1 \| Credit
Assets [Abstract]
Derivative assets: (1)	0	0
Liabilities [Abstract]
Derivative liabilities: (1)	0	0
Recurring \| Level 1 \| Equity market
Assets [Abstract]
Derivative assets: (1)	0	0
Liabilities [Abstract]
Derivative liabilities: (1)	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	3,613	3,566
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	71,747	69,821
Equity securities	25	27
Short-term investments	475	359
Derivative assets: (1)	2,608	2,247
Market risk benefit assets	0	0
Separate account assets	87,420	84,936
Total assets	162,275	157,390
Liabilities [Abstract]
Market risk benefit liabilities	0	0
Derivative liabilities: (1)	3,252	3,918
Embedded derivatives on index-linked annuities (2)	0	0
Total liabilities	3,252	3,918
Recurring \| Level 2 \| Interest rate
Assets [Abstract]
Derivative assets: (1)	407	304
Liabilities [Abstract]
Derivative liabilities: (1)	1,995	2,802
Recurring \| Level 2 \| Foreign currency exchange rate
Assets [Abstract]
Derivative assets: (1)	667	716
Liabilities [Abstract]
Derivative liabilities: (1)	9	18
Recurring \| Level 2 \| Credit
Assets [Abstract]
Derivative assets: (1)	15	10
Liabilities [Abstract]
Derivative liabilities: (1)	0	0
Recurring \| Level 2 \| Equity market
Assets [Abstract]
Derivative assets: (1)	1,519	1,217
Liabilities [Abstract]
Derivative liabilities: (1)	1,248	1,098
Recurring \| Level 2 \| U.S. corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	32,283	31,418
Recurring \| Level 2 \| Foreign corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	10,276	9,978
Recurring \| Level 2 \| U.S. government and agency
Assets [Abstract]
Fixed maturity securities, estimated fair value	4,674	4,450
Recurring \| Level 2 \| RMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	7,576	7,514
Recurring \| Level 2 \| CMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	6,641	6,578
Recurring \| Level 2 \| ABS
Assets [Abstract]
Fixed maturity securities, estimated fair value	5,293	5,041
Recurring \| Level 2 \| State and political subdivision
Assets [Abstract]
Fixed maturity securities, estimated fair value	3,949	3,799
Recurring \| Level 2 \| Foreign Government
Assets [Abstract]
Fixed maturity securities, estimated fair value	1,055	1,043
Recurring \| Level 3
Assets [Abstract]
Fixed maturity securities, estimated fair value	2,325	2,190
Equity securities	25	27
Short-term investments	0	0
Derivative assets: (1)	34	37
Market risk benefit assets	510	483
Separate account assets	0	0
Total assets	2,894	2,737
Liabilities [Abstract]
Market risk benefit liabilities	10,729	10,389
Derivative liabilities: (1)	1	2
Embedded derivatives on index-linked annuities (2)	5,164	3,932
Total liabilities	15,894	14,323
Recurring \| Level 3 \| Interest rate
Assets [Abstract]
Derivative assets: (1)	0	0
Liabilities [Abstract]
Derivative liabilities: (1)	0	0
Recurring \| Level 3 \| Foreign currency exchange rate
Assets [Abstract]
Derivative assets: (1)	26	29
Liabilities [Abstract]
Derivative liabilities: (1)	0	0
Recurring \| Level 3 \| Credit
Assets [Abstract]
Derivative assets: (1)	8	8
Liabilities [Abstract]
Derivative liabilities: (1)	1	2
Recurring \| Level 3 \| Equity market
Assets [Abstract]
Derivative assets: (1)	0	0
Liabilities [Abstract]
Derivative liabilities: (1)	0	0
Recurring \| Level 3 \| U.S. corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	1,329	1,189
Recurring \| Level 3 \| Foreign corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	607	598
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	14	14
Recurring \| Level 3 \| CMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	33	33
Recurring \| Level 3 \| ABS
Assets [Abstract]
Fixed maturity securities, estimated fair value	303	318
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	$ 39	$ 38