FAIR VALUE MEASUREMENTS - Changes in Investments and Derivatives Carried at Fair Value Classified as Level 3 (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 1,797	$ 1,095	$ 1,471	$ 1,021
Net investment gains (losses) included in earnings	(1)	(56)	1	(135)
Unrealized gains (losses) included in other comprehensive income (loss)	(97)	(14)	(311)	(42)
Purchases	306	109	698	283
Issuances	0	0	0	17
Sales	0	(8)	0	(31)
Settlements	(232)	(8)	(314)	(35)
Transfers into Level 3	68	0	496	55
Transfers out of Level 3	(24)	(44)	(224)	(59)
Balance, end of period	1,817	1,074	1,817	1,074
Change in unrealized gains (losses) still held	(1)	(72)	(3)	(178)
Foreign currency swaps
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	0	(200)	0	(98)
Net investment gains (losses) included in earnings	0	(57)	0	(158)
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	(257)	0	(257)
Changes in unrealized gain (losses) still held	0	(57)	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	311	258	291	224
Net investment gains (losses) included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(12)	(4)	(81)	(19)
Purchases	56	35	222	99
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(21)	0	(59)	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	(24)	(39)	(63)	(54)
Balance, end of period	310	250	310	250
Change in unrealized gains (losses) still held	0	(4)	0	(19)
Fixed maturity securities \| Public utilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	537	480	493	422
Net investment gains (losses) included in earnings	1	0	2	0
Unrealized gains (losses) included in other comprehensive income (loss)	(30)	(3)	(111)	(13)
Purchases	7	54	35	132
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(8)	(8)	(40)	(18)
Transfers into Level 3	0	0	128	0
Transfers out of Level 3	0	0	0	0
Balance, end of period	507	523	507	523
Change in unrealized gains (losses) still held	1	(3)	1	(13)
Fixed maturity securities \| Sovereign and supranational
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	36	45	43	48
Net investment gains (losses) included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(2)	0	(9)	(3)
Purchases	0	0	0	0
Issuances	0	0	0	0
Sales	0	0	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	34	45	34	45
Change in unrealized gains (losses) still held	0	0	0	(3)
Fixed maturity securities \| Banks/financial institutions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	91	38	45	24
Net investment gains (losses) included in earnings	1	0	1	0
Unrealized gains (losses) included in other comprehensive income (loss)	(12)	0	(14)	(1)
Purchases	88	8	121	23
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(20)	0	(23)	0
Transfers into Level 3	0	0	18	0
Transfers out of Level 3	0	0	0	0
Balance, end of period	148	46	148	46
Change in unrealized gains (losses) still held	0	0	0	(1)
Fixed maturity securities \| Other corporate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	632	316	426	299
Net investment gains (losses) included in earnings	0	2	0	2
Unrealized gains (losses) included in other comprehensive income (loss)	(41)	(7)	(96)	(5)
Purchases	145	0	267	0
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(183)	0	(185)	(17)
Transfers into Level 3	68	0	350	32
Transfers out of Level 3	0	(5)	(141)	(5)
Balance, end of period	621	306	621	306
Change in unrealized gains (losses) still held	0	(7)	0	(5)
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	190	158	173	102
Net investment gains (losses) included in earnings	(3)	(1)	(2)	21
Unrealized gains (losses) included in other comprehensive income (loss)	0	0	0	0
Purchases	10	12	53	29
Issuances	0	0	0	17
Sales	0	(8)	0	(8)
Settlements	0	0	(7)	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	(20)	0
Balance, end of period	197	161	197	161
Change in unrealized gains (losses) still held	$ (2)	$ (1)	$ (4)	$ 21

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 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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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 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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