FAIR VALUE MEASUREMENTS - Changes in Investments and Derivatives Carried at Fair Value Classified as Level 3 (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 1,460	$ 1,140	$ 1,471	$ 1,021
Net investment gains (losses) included in earnings	(5)	(107)	2	(79)
Unrealized gains (losses) included in other comprehensive income (loss)	(142)	22	(214)	(28)
Purchases	297	70	392	174
Issuances	0	17	0	17
Sales	0	(23)	0	(23)
Settlements	(61)	(24)	(82)	(27)
Transfers into Level 3	258	0	428	55
Transfers out of Level 3	(10)	0	(200)	(15)
Balance, end of period	1,797	1,095	1,797	1,095
Change in unrealized gains (losses) still held	(6)	(120)	(1)	(101)
Foreign currency swaps
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	0	(80)	0	(98)
Net investment gains (losses) included in earnings	0	(120)	0	(101)
Unrealized gains or losses included in other comprehensive income (loss)	0	0	0	(1)
Purchases	0	0	0	0
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	0	0	0	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Balance, end of period	0	(200)	0	(200)
Changes in unrealized gain (losses) still held	0	(120)	0	(101)
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	318	204	291	224
Net investment gains (losses) included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(54)	0	(69)	(15)
Purchases	90	54	166	64
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(36)	0	(38)	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	(7)	0	(39)	(15)
Balance, end of period	311	258	311	258
Change in unrealized gains (losses) still held	0	0	0	0
Fixed maturity securities \| Public utilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	585	479	493	422
Net investment gains (losses) included in earnings	1	0	1	0
Unrealized gains (losses) included in other comprehensive income (loss)	(44)	8	(81)	(10)
Purchases	19	0	28	78
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(24)	(7)	(32)	(10)
Transfers into Level 3	0	0	128	0
Transfers out of Level 3	0	0	0	0
Balance, end of period	537	480	537	480
Change in unrealized gains (losses) still held	0	0	1	0
Fixed maturity securities \| Sovereign and supranational
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	41	68	43	48
Net investment gains (losses) included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(5)	0	(7)	(3)
Purchases	0	0	0	0
Issuances	0	0	0	0
Sales	0	(23)	0	(23)
Settlements	0	0	0	0
Transfers into Level 3	0	0	0	23
Transfers out of Level 3	0	0	0	0
Balance, end of period	36	45	36	45
Change in unrealized gains (losses) still held	0	0	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	60	28	45	24
Net investment gains (losses) included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(2)	0	(2)	(1)
Purchases	33	10	33	15
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	0	0	(3)	0
Transfers into Level 3	0	0	18	0
Transfers out of Level 3	0	0	0	0
Balance, end of period	91	38	91	38
Change in unrealized gains (losses) still held	0	0	0	0
Fixed maturity securities \| Other corporate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	290	319	426	299
Net investment gains (losses) included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(37)	14	(55)	2
Purchases	122	0	122	0
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(1)	(17)	(2)	(17)
Transfers into Level 3	258	0	282	32
Transfers out of Level 3	0	0	(141)	0
Balance, end of period	632	316	632	316
Change in unrealized gains (losses) still held	0	0	0	0
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	166	122	173	102
Net investment gains (losses) included in earnings	(6)	13	1	22
Unrealized gains (losses) included in other comprehensive income (loss)	0	0	0	0
Purchases	33	6	43	17
Issuances	0	17	0	17
Sales	0	0	0	0
Settlements	0	0	(7)	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	(3)	0	(20)	0
Balance, end of period	190	158	190	158
Change in unrealized gains (losses) still held	$ (6)	$ 0	$ (2)	$ 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 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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