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, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 1,840	$ 1,797	$ 1,987	$ 1,471
Net investment gains (losses) included in earnings	(7)	(1)	(13)	1
Unrealized gains (losses) included in other comprehensive income (loss)	(69)	(97)	(76)	(311)
Purchases	127	306	577	698
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(17)	(232)	(171)	(314)
Transfers into Level 3	42	68	184	496
Transfers out of Level 3	(109)	(24)	(681)	(224)
Balance, end of period	1,807	1,817	1,807	1,817
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities still held at the end of the period included in earnings	(3)	(1)	(7)	(3)
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	652	311	343	291
Net investment gains (losses) included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(13)	(12)	(23)	(81)
Purchases	55	56	383	222
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(11)	(21)	(144)	(59)
Transfers into Level 3	0	0	124	0
Transfers out of Level 3	(3)	(24)	(3)	(63)
Balance, end of period	680	310	680	310
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities still held at the end of the period included in earnings	0	0	1	0
Fixed maturity securities | Public utilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	302	537	497	493
Net investment gains (losses) included in earnings	0	1	0	2
Unrealized gains (losses) included in other comprehensive income (loss)	(12)	(30)	(18)	(111)
Purchases	36	7	36	35
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(6)	(8)	(15)	(40)
Transfers into Level 3	0	0	18	128
Transfers out of Level 3	(61)	0	(259)	0
Balance, end of period	259	507	259	507
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities still held at the end of the period included in earnings	0	1	1	1
Fixed maturity securities | Sovereign and supranational
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	32	36	37	43
Net investment gains (losses) included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(1)	(2)	(4)	(9)
Purchases	0	0	0	0
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	0	0	(2)	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Balance, end of period	31	34	31	34
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities still held at the end of the period included in earnings	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	69	91	159	45
Net investment gains (losses) included in earnings	0	1	0	1
Unrealized gains (losses) included in other comprehensive income (loss)	(2)	(12)	2	(14)
Purchases	0	88	0	121
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	0	(20)	(7)	(23)
Transfers into Level 3	3	0	3	18
Transfers out of Level 3	0	0	(87)	0
Balance, end of period	70	148	70	148
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities still held at the end of the period included in earnings	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	572	632	742	426
Net investment gains (losses) included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)	(41)	(41)	(33)	(96)
Purchases	36	145	148	267
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	0	(183)	(3)	(185)
Transfers into Level 3	39	68	39	350
Transfers out of Level 3	(42)	0	(329)	(141)
Balance, end of period	564	621	564	621
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities still held at the end of the period included in earnings	0	0	0	0
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	213	190	209	173
Net investment gains (losses) included in earnings	(7)	(3)	(13)	(2)
Unrealized gains (losses) included in other comprehensive income (loss)	0	0	0	0
Purchases	0	10	10	53
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	0	0	0	(7)
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	(3)	0	(3)	(20)
Balance, end of period	203	197	203	197
Changes in unrealized gains (losses) relating to Level 3 assets and liabilities still held at the end of the period included in earnings	$ (3)	$ (2)	$ (9)	$ (4)