INVESTMENTS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
INVESTMENTS - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Debt Securities, Available-for-Sale [Line Items]
Non-accrual status	$ 3		$ 3
Increase in securities received as collateral	2
Decrease in collateral securities held		$ (48)
U.S. corporate public securities
Debt Securities, Available-for-Sale [Line Items]
Securities	1,004		1,200
Fair Value \| U.S. corporate public securities
Debt Securities, Available-for-Sale [Line Items]
Securities	$ 1,047		$ 1,224

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 320
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-Topic 320
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-Topic 320
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-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

FORTITUDE LIFE INSURANCE & ANNUITY CO 10-Q