Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Name:	us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

INVESTMENTS - SUCCESSOR COMPANY - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale [Line Items]
Accumulated other comprehensive income		$ 111,000,000	$ 170,000,000
Accrued investment income, write-down	$ 0	0	200,000
Fixed Maturities
Debt Securities, Available-for-Sale [Line Items]
Assets deposited with governmental authorities		7,000,000	12,300,000
Equity securities
Debt Securities, Available-for-Sale [Line Items]
Securities		106,000,000	0
Equity securities \| Fair Value
Debt Securities, Available-for-Sale [Line Items]
Securities		103,000,000
U.S. corporate public securities
Debt Securities, Available-for-Sale [Line Items]
Securities		311,000,000	$ 0
U.S. corporate public securities \| Fair Value
Debt Securities, Available-for-Sale [Line Items]
Securities		326,000,000
AOCI, Gain (Loss), Debt Securities, Available-for-Sale, without Allowance for Credit Loss, Parent
Debt Securities, Available-for-Sale [Line Items]
Accumulated other comprehensive income		0
AOCI, Gain (Loss), Debt Securities, Available-For-Sale, Allowance For Credit Loss, Parent
Debt Securities, Available-for-Sale [Line Items]
Accumulated other comprehensive income		$ 0