FAIR VALUE MEASUREMENTS - Changes in Investments Carried at Fair Value Classified as Level 3 (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 1,987	$ 1,471
Net investment gains (losses) included in earnings	35	5
Unrealized gains (losses) included in other comprehensive income (loss)	23	(288)
Purchases	669	886
Issuances	0	0
Sales	0	0
Settlements	(186)	(359)
Transfers into Level 3	215	496
Transfers out of Level 3	(714)	(224)
Balance, end of period	2,029	1,987
Change in unrealized gains (losses) still held	$ 40	$ (2)
Change in unrealized gains (losses) still held ext list	Net investment gains (losses)	Net investment gains (losses)
Net investment gains (losses) included in earnings ext list	Net investment gains (losses)	Net investment gains (losses)
Unrealized gains (losses) included in other comprehensive income (loss) ext list	Total other comprehensive income (loss) before income taxes	Total other comprehensive income (loss) before income taxes
Fixed maturity securities \| Mortgage- and asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 343	$ 291
Net investment gains (losses) included in earnings	0	(4)
Unrealized gains (losses) included in other comprehensive income (loss)	1	(76)
Purchases	430	273
Issuances	0	0
Sales	0	0
Settlements	(154)	(78)
Transfers into Level 3	155	0
Transfers out of Level 3	(3)	(63)
Balance, end of period	772	343
Change in unrealized gains (losses) still held	0	(4)
Fixed maturity securities \| Public utilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	497	493
Net investment gains (losses) included in earnings	0	4
Unrealized gains (losses) included in other comprehensive income (loss)	(2)	(99)
Purchases	46	35
Issuances	0	0
Sales	0	0
Settlements	(17)	(64)
Transfers into Level 3	18	128
Transfers out of Level 3	(289)	0
Balance, end of period	253	497
Change in unrealized gains (losses) still held	0	1
Fixed maturity securities \| Sovereign and supranational
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	37	43
Net investment gains (losses) included in earnings	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(3)	(6)
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	(4)	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance, end of period	30	37
Change in unrealized gains (losses) still held	0	0
Fixed maturity securities \| Banks/financial institutions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	159	45
Net investment gains (losses) included in earnings	0	1
Unrealized gains (losses) included in other comprehensive income (loss)	10	(14)
Purchases	0	132
Issuances	0	0
Sales	0	0
Settlements	(7)	(23)
Transfers into Level 3	3	18
Transfers out of Level 3	(87)	0
Balance, end of period	78	159
Change in unrealized gains (losses) still held	0	0
Fixed maturity securities \| Other corporate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	742	426
Net investment gains (losses) included in earnings	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	17	(93)
Purchases	183	387
Issuances	0	0
Sales	0	0
Settlements	(4)	(187)
Transfers into Level 3	39	350
Transfers out of Level 3	(329)	(141)
Balance, end of period	648	742
Change in unrealized gains (losses) still held	0	0
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	209	173
Net investment gains (losses) included in earnings	35	4
Unrealized gains (losses) included in other comprehensive income (loss)	0	0
Purchases	10	59
Issuances	0	0
Sales	0	0
Settlements	0	(7)
Transfers into Level 3	0	0
Transfers out of Level 3	(6)	(20)
Balance, end of period	248	209
Change in unrealized gains (losses) still held	$ 40	$ 1

Indicates line item in statement in which net income is reported that includes unrealized gain (loss) from asset measured at fair value using unobservable input (level 3) and still held.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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- Definition

Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Name Accounting Standards Codification
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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Indicates line item in statement in which net income is reported that includes gain (loss) from asset measured at fair value using unobservable input (level 3).

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Indicates line item in statement in which other comprehensive income (OCI) is reported that includes gain (loss) from asset measured at fair value using unobservable input (level 3).

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