AVAILABLE-FOR-SALE FIXED MATURITY SECURITIES - Schedule of Allowance for Credit Loss for Available-for-Sale Fixed Maturity Securities (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ (5)	$ (4)	$ (12)	$ (27)
Credit losses recognized on securities for which credit losses were not previously recorded			(4)	(8)
Reductions for securities sold during the period				15
Changes in previously recorded allowance	4	(1)	13	8
Ending balance	(1)	(5)	(3)	(12)
U.S. State and Municipal
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward]
Beginning balance	(4)	(3)	0	0
Credit losses recognized on securities for which credit losses were not previously recorded			0	0
Reductions for securities sold during the period				0
Changes in previously recorded allowance	4	(1)	0	0
Ending balance	0	(4)	0	0
Corporate Debt Securities
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward]
Beginning balance	(1)	(1)	(10)	(26)
Credit losses recognized on securities for which credit losses were not previously recorded			(3)	(7)
Reductions for securities sold during the period				15
Changes in previously recorded allowance	0	0	11	8
Ending balance	(1)	(1)	(2)	(10)
Residential Mortgage Backed Securities
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward]
Beginning balance	0	0	(1)	(1)
Credit losses recognized on securities for which credit losses were not previously recorded			0	0
Reductions for securities sold during the period				0
Changes in previously recorded allowance	0	0	1	0
Ending balance	0	0	0	(1)
Collateralized Debt Securities
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward]
Beginning balance	0	0	(1)	0
Credit losses recognized on securities for which credit losses were not previously recorded			(1)	(1)
Reductions for securities sold during the period				0
Changes in previously recorded allowance	0	0	1	0
Ending balance	$ 0	$ 0	$ (1)	$ (1)

Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

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Balance Type:	credit
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- Definition

Amount of expense for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), for which no credit loss was previously recorded.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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- Definition

Amount of expense (reversal of expense) for allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), not intended to be sold and not more likely than not will be required to sell before recovery of amortized cost basis, with previously recorded allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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- Definition

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

+ References

No definition available.

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- Definition

Amount of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

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