INVESTMENTS - Schedule of Gross Gains (Losses) from Dispositions of Fixed Maturity and Equity Securities (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Investments, Debt and Equity Securities [Abstract]
Proceeds from sales of fixed maturity securities - available for sale	$ 124	$ 68	$ 341	$ 142
Gross gains from dispositions	9	4	17	6
Gross losses from dispositions	(8)	(5)	(29)	(8)
Proceeds from sales of fixed maturity securities - held to maturity	0	0	0	10
Gross gains from sales	0	0	0	0
Gross losses from sales	0	0	0	(1)	$ (1)
Proceeds from sales of equity securities	0	2	0	2
Gross gains from dispositions	0	0	0	0
Gross losses from dispositions	$ 0	$ 0	$ 0	$ 0

Debt Security, Held-To-Maturity, Sold, Realized Gain

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- Definition

Debt Security, Held-To-Maturity, Sold, Realized Loss

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

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

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Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
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Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481830/320-10-45-11

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Amount of cash inflow from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as investing activity.

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-Topic 230
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The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer.

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