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	$ 76,852	$ 74,757
Equity securities	63	66
Short-term investments	498	299
Derivative assets: (1)	2,627	2,271
Market risk benefit assets	510	483
Separate account assets	81,124	78,880
Liabilities [Abstract]
Market risk benefit liabilities	10,751	10,411	$ 16,062
Derivative liabilities: (1)	3,252	3,911
Recurring
Assets [Abstract]
Fixed maturity securities, estimated fair value	76,852	74,757
Equity securities	63	66
Short-term investments	498	299
Derivative assets: (1)	2,627	2,271
Market risk benefit assets	510	483
Separate account assets	81,124	78,880
Total assets	161,674	156,756
Liabilities [Abstract]
Market risk benefit liabilities	10,751	10,411
Derivative liabilities: (1)	3,252	3,911
Embedded derivatives on index-linked annuities	5,164	3,932
Total liabilities	19,167	18,254
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)	678	732
Liabilities [Abstract]
Derivative liabilities: (1)	8	9
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	33,161	32,162
Recurring | Foreign corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	10,801	10,492
Recurring | U.S. government and agency
Assets [Abstract]
Fixed maturity securities, estimated fair value	8,164	7,898
Recurring | RMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	7,554	7,491
Recurring | CMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	6,600	6,537
Recurring | ABS
Assets [Abstract]
Fixed maturity securities, estimated fair value	5,591	5,355
Recurring | State and political subdivision
Assets [Abstract]
Fixed maturity securities, estimated fair value	3,887	3,741
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	3,551	3,507
Equity securities	14	12
Short-term investments	398	206
Derivative assets: (1)	0	0
Market risk benefit assets	0	0
Separate account assets	20	29
Total assets	3,983	3,754
Liabilities [Abstract]
Market risk benefit liabilities	0	0
Derivative liabilities: (1)	0	0
Embedded derivatives on index-linked annuities	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	3,551	3,507
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	70,976	69,060
Equity securities	24	27
Short-term investments	100	93
Derivative assets: (1)	2,593	2,234
Market risk benefit assets	0	0
Separate account assets	81,104	78,851
Total assets	154,797	150,265
Liabilities [Abstract]
Market risk benefit liabilities	0	0
Derivative liabilities: (1)	3,251	3,909
Embedded derivatives on index-linked annuities	0	0
Total liabilities	3,251	3,909
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)	652	703
Liabilities [Abstract]
Derivative liabilities: (1)	8	9
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	31,832	30,973
Recurring | Level 2 | Foreign corporate
Assets [Abstract]
Fixed maturity securities, estimated fair value	10,194	9,894
Recurring | Level 2 | U.S. government and agency
Assets [Abstract]
Fixed maturity securities, estimated fair value	4,613	4,391
Recurring | Level 2 | RMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	7,540	7,477
Recurring | Level 2 | CMBS
Assets [Abstract]
Fixed maturity securities, estimated fair value	6,567	6,504
Recurring | Level 2 | ABS
Assets [Abstract]
Fixed maturity securities, estimated fair value	5,288	5,037
Recurring | Level 2 | State and political subdivision
Assets [Abstract]
Fixed maturity securities, estimated fair value	3,887	3,741
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	10,751	10,411
Derivative liabilities: (1)	1	2
Embedded derivatives on index-linked annuities	5,164	3,932
Total liabilities	15,916	14,345
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