Changes in and Reclassifications From Accumulated Other Comprehensive Income - AOCI Rollforward (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 1,883	$ 3,185	$ 2,552	$ 2,005
OCI before reclassifications	(12)	(238)	663
Amounts reclassified from AOCI	2
OCI, net of tax	(10)	(274)	564	888
Ending balance	2,153	2,597	3,185	2,552
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	0	1,281	717	(171)
OCI before reclassifications				925
Amounts reclassified from AOCI		(36)	(99)	(37)
OCI, net of tax	(10)	(274)	564	888
Ending balance	(10)	1,007	1,281	717
Net Unrealized Gain on Fixed Maturities
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	0	1,282	717	(173)
OCI before reclassifications	(12)	(238)	665	927
Amounts reclassified from AOCI	2	(37)	(100)	(37)
OCI, net of tax	(10)	(275)	565	890
Ending balance	(10)	1,007	1,282	717
Unrealized Losses on Fixed Maturities for Which an ACL Has Been Recorded
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	0	0	0
OCI before reclassifications	0	0	(1)
Amounts reclassified from AOCI	0	0	1
OCI, net of tax	0	0	0
Ending balance	0	0	0	0
Net Gain on Cash Flow Hedging Instruments
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	0	(1)	0	0
OCI before reclassifications	0	0	(1)	0
Amounts reclassified from AOCI	0	1	0	0
OCI, net of tax	0	1	(1)	0
Ending balance	0	0	(1)	0
Foreign Currency Translation Adjustments
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	0	0	0	2
OCI before reclassifications	0	0	0	(2)
Amounts reclassified from AOCI	0	0	0	0
OCI, net of tax	0	0	0	(2)
Ending balance	$ 0	$ 0	$ 0	$ 0

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 after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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

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

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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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