FAIR VALUE MEASUREMENTS - Changes in Investments and Derivatives Carried at Fair Value Classified as Level 3 (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 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	7	28
Unrealized gains (losses) included in other comprehensive income (loss)	(72)	(50)
Purchases	95	104
Issuances	0	0
Sales	0	0
Settlements	(21)	(3)
Transfers into Level 3	170	55
Transfers out of Level 3	(190)	(15)
Balance, end of period	1,460	1,140
Change in unrealized gains (losses) still held	4	19
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	19
Unrealized gains or 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	0
Balance, end of period	0	(80)
Changes in unrealized gain (losses) still held	0	19
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	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(15)	(15)
Purchases	76	10
Issuances	0	0
Sales	0	0
Settlements	(2)	0
Transfers into Level 3	0	0
Transfers out of Level 3	(32)	(15)
Balance, end of period	318	204
Change in unrealized gains (losses) still held	0	0
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	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(37)	(18)
Purchases	9	78
Issuances	0	0
Sales	0	0
Settlements	(8)	(3)
Transfers into Level 3	128	0
Transfers out of Level 3	0	0
Balance, end of period	585	479
Change in unrealized gains (losses) still held	0	0
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)	(2)	(3)
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	0	0
Transfers into Level 3	0	23
Transfers out of Level 3	0	0
Balance, end of period	41	68
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	45	24
Net investment gains (losses) included in earnings	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	0	(1)
Purchases	0	5
Issuances	0	0
Sales	0	0
Settlements	(3)	0
Transfers into Level 3	18	0
Transfers out of Level 3	0	0
Balance, end of period	60	28
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	426	299
Net investment gains (losses) included in earnings	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(18)	(12)
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	(1)	0
Transfers into Level 3	24	32
Transfers out of Level 3	(141)	0
Balance, end of period	290	319
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	173	102
Net investment gains (losses) included in earnings	7	9
Unrealized gains (losses) included in other comprehensive income (loss)	0	0
Purchases	10	11
Issuances	0	0
Sales	0	0
Settlements	(7)	0
Transfers into Level 3	0	0
Transfers out of Level 3	(17)	0
Balance, end of period	166	122
Change in unrealized gains (losses) still held	$ 4	$ 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 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 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 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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