FAIR VALUE MEASUREMENTS - Changes in Investments and Derivatives Carried at Fair Value Classified as Level 3 (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 1,471	$ 1,021
Net investment gains (losses) included in earnings	$ 5	(135)
Net investment gains (losses) included in earnings ext list	Net investment gains (losses)
Unrealized gains (losses) included in other comprehensive income (loss)	$ (288)	(65)
Unrealized gains (losses) included in other comprehensive income (loss) ext list	Total other comprehensive income (loss) before income taxes
Purchases	$ 886	490
Issuances	0	17
Sales	0	(33)
Settlements	(359)	(38)
Transfers into Level 3	496	107
Transfers out of Level 3	(224)
Transfers out of Level 3		107
Balance, end of period	1,987	1,471
Change in unrealized gains (losses) still held	$ (2)	(217)
Change in unrealized gains (losses) still held ext list	Net investment gains (losses)
Foreign currency swaps
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	$ 0	(98)
Net investment gains (losses) included in earnings	0	(158)
Unrealized gains (losses) included in other comprehensive income (loss)	0	(1)
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	257
Balance, end of period	0	0
Change in unrealized gains (losses) still held	0	(158)
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	291	224
Net investment gains (losses) included in earnings	(4)	0
Unrealized gains (losses) included in other comprehensive income (loss)	(76)	(25)
Purchases	273	169
Issuances	0	0
Sales	0	0
Settlements	(78)	0
Transfers into Level 3	0	0
Transfers out of Level 3	(63)	(77)
Balance, end of period	343	291
Change in unrealized gains (losses) still held	(4)	(24)
Fixed maturity securities \| Public utilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	493	422
Net investment gains (losses) included in earnings	4	0
Unrealized gains (losses) included in other comprehensive income (loss)	(99)	(21)
Purchases	35	167
Issuances	0	0
Sales	0	(2)
Settlements	(64)	(21)
Transfers into Level 3	128	0
Transfers out of Level 3	0	(52)
Balance, end of period	497	493
Change in unrealized gains (losses) still held	1	(23)
Fixed maturity securities \| Sovereign and supranational
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	43	48
Net investment gains (losses) included in earnings	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(6)	(5)
Purchases	0	0
Issuances	0	0
Sales	0	(23)
Settlements	0	0
Transfers into Level 3	0	23
Transfers out of Level 3	0	0
Balance, end of period	37	43
Change in unrealized gains (losses) still held	0	(4)
Fixed maturity securities \| Banks/financial institutions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	45	24
Net investment gains (losses) included in earnings	1	0
Unrealized gains (losses) included in other comprehensive income (loss)	(14)	(2)
Purchases	132	23
Issuances	0	0
Sales	0	0
Settlements	(23)	0
Transfers into Level 3	18	0
Transfers out of Level 3	0	0
Balance, end of period	159	45
Change in unrealized gains (losses) still held	0	(2)
Fixed maturity securities \| Other corporate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	426	299
Net investment gains (losses) included in earnings	0	2
Unrealized gains (losses) included in other comprehensive income (loss)	(93)	(11)
Purchases	387	90
Issuances	0	0
Sales	0	0
Settlements	(187)	(17)
Transfers into Level 3	350	84
Transfers out of Level 3	(141)	(21)
Balance, end of period	742	426
Change in unrealized gains (losses) still held	0	(27)
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	173	102
Net investment gains (losses) included in earnings	4	21
Unrealized gains (losses) included in other comprehensive income (loss)	0	0
Purchases	59	41
Issuances	0	17
Sales	0	(8)
Settlements	(7)	0
Transfers into Level 3	0	0
Transfers out of Level 3	(20)	0
Balance, end of period	209	173
Change in unrealized gains (losses) still held	$ 1	$ 21

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

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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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Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

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Amount of unrealized gain (loss) recognized in income for derivative asset (liability) after deduction of derivative liability (asset), measured at fair value using unobservable input (level 3) and still held.

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

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

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Amount of issuances of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (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 transfers of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset) into level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (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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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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