RESERVES FOR LOSSES AND LAE - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Reserves For Losses And LAE [Line Items]
Current year incurred losses	$ 1,399	$ 1,403
Prior year incurred development	(24)	$ (9)
Catastrophe
Reserves For Losses And LAE [Line Items]
Increase (decrease) in earned premium growth	(60)
Higher Premiums Earned
Reserves For Losses And LAE [Line Items]
Current year incurred losses	$ 56

Reserves For Losses And LAE [Line Items]

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- Definition

Amount, after effects of reinsurance, of increase (decrease) in the liability for unpaid claims and claims adjustment expense.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480081/944-40-50-3

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- Definition

Amount, after effects of reinsurance, of expense for claims incurred in the current reporting period and related claims settlement costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480081/944-40-50-3

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- Definition

Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs.

+ References

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