Accumulated Other Comprehensive Income (AOCI) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
AOCI, Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax			$ (614)
AOCI, net of tax, end of period	$ (827)		(827)
AOCI on Net Unrecognized Investment Gain (Loss)
AOCI, Before Tax
AOCI, before tax, beginning of period	(838)	$ (564)	(847)	$ 792
Other comprehensive income before reclassification, before tax	(369)	(514)	(364)	(1,867)
Reclassification adjustment, before tax	0	0	4	(3)
Effect on other comprehensive income, before tax	(369)	(514)	(360)	(1,870)
AOCI, before tax, end of period	(1,207)	(1,078)	(1,207)	(1,078)
AOCI, Tax
AOCI, tax, beginning of period	(179)	(119)	(182)	165
Other comprehensive income before reclassification, tax	(79)	(109)	(77)	(392)
Reclassification adjustment, tax	0	0	1	(1)
Effect on other comprehensive income, tax	(79)	(109)	(76)	(393)
AOCI, tax, end of period	(258)	(228)	(258)	(228)
AOCI, Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax	(659)	(445)	(665)	627
Other comprehensive income before reclassification, net of tax	(290)	(405)	(287)	(1,475)
Reclassification adjustment, net of tax	0	0	3	(2)
Effect on other comprehensive income, net of tax	(290)	(405)	(284)	(1,477)
AOCI, net of tax, end of period	(949)	(850)	(949)	(850)
AOCI on Pension Obligations
AOCI, Before Tax
AOCI, before tax, beginning of period	29	27	36	27
Other comprehensive income before reclassification, before tax	0	0	(5)	0
Reclassification adjustment, before tax	0	0	(2)	0
Effect on other comprehensive income, before tax	0	0	(7)	0
AOCI, before tax, end of period	29	27	29	27
AOCI, Tax
AOCI, tax, beginning of period	7	7	9	7
Other comprehensive income before reclassification, tax	0	0	(2)	0
Reclassification adjustment, tax	0	0	0	0
Effect on other comprehensive income, tax	0	0	(2)	0
AOCI, tax, end of period	7	7	7	7
AOCI, Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax	22	20	27	20
Other comprehensive income before reclassification, net of tax	0	0	(3)	0
Reclassification adjustment, net of tax	0	0	(2)	0
Effect on other comprehensive income, net of tax	0	0	(5)	0
AOCI, net of tax, end of period	22	20	22	20
AOCI on Life Policy Reserves, Reinsurance Recoverable And Other
AOCI, Before Tax
AOCI, before tax, beginning of period	13	(67)	29	(444)
Other comprehensive income before reclassification, before tax	111	120	95	497
Reclassification adjustment, before tax	0	0	0	0
Effect on other comprehensive income, before tax	111	120	95	497
AOCI, before tax, end of period	124	53	124	53
AOCI, Tax
AOCI, tax, beginning of period	2	(14)	5	(93)
Other comprehensive income before reclassification, tax	22	25	19	104
Reclassification adjustment, tax	0	0	0	0
Effect on other comprehensive income, tax	22	25	19	104
AOCI, tax, end of period	24	11	24	11
AOCI, Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax	11	(53)	24	(351)
Other comprehensive income before reclassification, net of tax	89	95	76	393
Reclassification adjustment, net of tax	0	0	0	0
Effect on other comprehensive income, net of tax	89	95	76	393
AOCI, net of tax, end of period	100	42	100	42
Summary of AOCI
AOCI, Before Tax
AOCI, before tax, beginning of period	(796)	(604)	(782)	375
Change in unrealized gains, net, on investments available for sale, before tax	(369)	(514)	(360)	(1,870)
Change in pension obligations, before tax	0	0	(7)	0
Change in life policy reserves, reinsurance recoverable and other, before tax	111	120	95	497
Effect on other comprehensive income, before tax	(258)	(394)	(272)	(1,373)
AOCI, before tax, end of period	(1,054)	(998)	(1,054)	(998)
AOCI, Tax
AOCI, tax, beginning of period	(170)	(126)	(168)	79
Change in unrealized gains, net, on investments available for sale, tax	(79)	(109)	(76)	(393)
Change in pension obligations, tax	0	0	(2)	0
Change in Life Policy Reserves, Reinsurance Recoverable and Other, Tax	22	25	19	104
Effect on other comprehensive income, tax	(57)	(84)	(59)	(289)
AOCI, tax, end of period	(227)	(210)	(227)	(210)
AOCI, Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax	(626)	(478)	(614)	296
Change in unrealized gains, net, on investments available for sale, net of tax	(290)	(405)	(284)	(1,477)
Change in pension obligations, net of tax	0	0	(5)	0
Change in Life Policy Reserves, Reinsurance Recoverable and Other, Net of Tax	89	95	76	393
Effect on other comprehensive income, net of tax	(201)	(310)	(213)	(1,084)
AOCI, net of tax, end of period	$ (827)	$ (788)	(827)	(788)
As originally reported | AOCI on Life Policy Reserves, Reinsurance Recoverable And Other
AOCI, Before Tax
AOCI, before tax, beginning of period			29	1
AOCI, Tax
AOCI, tax, beginning of period			5	0
AOCI, Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax			24	1
As originally reported | Summary of AOCI
AOCI, Before Tax
AOCI, before tax, beginning of period			(782)	820
AOCI, Tax
AOCI, tax, beginning of period			(168)	172
AOCI, Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax			(614)	648
As adjusted | AOCI on Life Policy Reserves, Reinsurance Recoverable And Other
AOCI, Before Tax
AOCI, before tax, beginning of period			0	(445)
AOCI, Tax
AOCI, tax, beginning of period			0	(93)
AOCI, Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax			0	(352)
As adjusted | Summary of AOCI
AOCI, Before Tax
AOCI, before tax, beginning of period			0	(445)
AOCI, Tax
AOCI, tax, beginning of period			0	(93)
AOCI, Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax			$ 0	$ (352)