Changes in and Reclassifications From Accumulated Other Comprehensive Income (Loss) - AOCI Rollforward (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 17,843	$ 18,556
OCI, net of tax	(4,048)	(998)	$ 1,118
Ending balance	13,631	17,843	18,556
Net Unrealized Gain (Loss) on Fixed Maturities, AFS
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,616	2,834	1,684
OCI, before Reclassifications, before Tax, Attributable to Parent	(5,611)	(1,307)	1,627
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	(282)	234	171
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	(5,329)	(1,541)	1,456
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	1,119	323	(306)
OCI, net of tax	(4,210)	(1,218)	1,150
Ending balance	(2,594)	1,616	2,834
AOCI, Gain (Loss), Debt Securities, Available-for-sale, with Allowance for Credit Loss, Parent
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(2)	(2)	(3)
OCI, before Reclassifications, before Tax, Attributable to Parent	(6)	0	1
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	0	0	0
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	(6)	0	1
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	1	0	0
OCI, net of tax	(5)	0	1
Ending balance	(7)	(2)	(2)
Foreign Currency Translation Adjustments
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	41	43	34
OCI, before Reclassifications, before Tax, Attributable to Parent	(13)	(3)	11
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	0	0	0
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	(13)	(3)	11
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	3	1	(2)
OCI, net of tax	(10)	(2)	9
Ending balance	31	41	43
Pension and Other Postretirement Plan Adjustments
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(1,489)	(1,717)	(1,672)
OCI, before Reclassifications, before Tax, Attributable to Parent	119	219	(117)
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	(62)	(70)	(60)
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	181	289	(57)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(38)	(61)	12
OCI, net of tax	143	228	(45)
Ending balance	(1,346)	(1,489)	(1,717)
AOCI, net of tax
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	172	1,170	52
OCI, before Reclassifications, before Tax, Attributable to Parent	(5,455)	(1,063)	1,552
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	(331)	200	137
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	(5,124)	(1,263)	1,415
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	1,076	265	(297)
OCI, net of tax	(4,048)	(998)	1,118
Ending balance	(3,876)	172	1,170
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	6	12	9
OCI, before Reclassifications, before Tax, Attributable to Parent	56	28	30
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	13	36	26
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	43	(8)	4
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(9)	2	(1)
OCI, net of tax	34	(6)	3
Ending balance	$ 40	$ 6	$ 12

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount before tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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