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, 2021	Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 1,021	$ 810
Net investment gains (losses) included in earnings	(135)	(124)
Unrealized gains (losses) included in other comprehensive income (loss)	(65)	38
Purchases	490	306
Issuances	17	0
Sales	(33)	(6)
Settlements	(38)	(12)
Transfers into Level 3	107	26
Transfers out of Level 3		(17)
Transfers out of level 3	107
Balance, end of period	1,471	1,021
Change in unrealized gains (losses) still held	(217)	(139)
Foreign currency swaps
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	(98)	43
Net investment gains (losses) included in earnings	(158)	(139)
Unrealized gains (losses) included in other comprehensive income (loss)	(1)	(2)
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	257	0
Balance, end of period	0	(98)
Change in unrealized gains (losses) still held	(158)	(139)
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	224	178
Net investment gains (losses) included in earnings	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(25)	9
Purchases	169	30
Issuances	0	0
Sales	0	0
Settlements	0	(2)
Transfers into Level 3	0	9
Transfers out of Level 3	(77)	0
Balance, end of period	291	224
Change in unrealized gains (losses) still held	(24)	0
Fixed maturity securities \| Public utilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	422	224
Net investment gains (losses) included in earnings	0	(1)
Unrealized gains (losses) included in other comprehensive income (loss)	(21)	19
Purchases	167	174
Issuances	0	0
Sales	(2)	0
Settlements	(21)	(9)
Transfers into Level 3	0	15
Transfers out of Level 3	(52)	0
Balance, end of period	493	422
Change in unrealized gains (losses) still held	(23)	0
Fixed maturity securities \| Sovereign and supranational
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	48	0
Net investment gains (losses) included in earnings	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(5)	0
Purchases	0	48
Issuances	0	0
Sales	(23)	0
Settlements	0	0
Transfers into Level 3	23	0
Transfers out of Level 3	0	0
Balance, end of period	43	48
Change in unrealized gains (losses) still held	(4)	0
Fixed maturity securities \| Banks/financial institutions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	24	23
Net investment gains (losses) included in earnings	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(2)	0
Purchases	23	1
Issuances	0	0
Sales	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance, end of period	45	24
Change in unrealized gains (losses) still held	(2)	0
Fixed maturity securities \| Other corporate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	299	262
Net investment gains (losses) included in earnings	2	0
Unrealized gains (losses) included in other comprehensive income (loss)	(11)	12
Purchases	90	39
Issuances	0	0
Sales	0	0
Settlements	(17)	(1)
Transfers into Level 3	84	2
Transfers out of Level 3	(21)	(15)
Balance, end of period	426	299
Change in unrealized gains (losses) still held	(27)	0
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	102	80
Net investment gains (losses) included in earnings	21	16
Unrealized gains (losses) included in other comprehensive income (loss)	0	0
Purchases	41	14
Issuances	17	0
Sales	(8)	(6)
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	(2)
Balance, end of period	173	102
Change in unrealized gains (losses) still held	$ 21	$ 0

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

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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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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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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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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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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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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 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 purchases 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 sales 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 settlements of financial instrument classified as a derivative asset (liability) after deduction of derivative liability, 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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Amount of transfers of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset) out of 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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