INVESTMENTS - Fair Value and Gross Unrealized Losses for Securities That Have Been in Continuous Unrealized Loss Position (Details) - Fixed Maturities [Member] - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	$ 4,528	$ 239
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	2,213	42
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	31,709	7,914
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	20,347	2,948
12 months or longer Unrealized Losses	11,362	4,966
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	2,315	197
Dollar-denominated | U.S. government and agencies
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	8	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	3	1
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	159	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	85	0
12 months or longer Unrealized Losses	74	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	5	0
Dollar-denominated | Municipalities
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	89	2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	57	2
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	854	82
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	735	79
12 months or longer Unrealized Losses	119	3
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	32	0
Dollar-denominated | Mortgage- and asset-backed securities
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	84	2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	42	2
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	936	278
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	640	278
12 months or longer Unrealized Losses	296	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	42	0
Dollar-denominated | Public utilities
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	180	5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	144	2
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,852	130
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,667	70
12 months or longer Unrealized Losses	185	60
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	36	3
Dollar-denominated | Sovereign and supranational
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	12	6
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	1
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	30	37
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	6
12 months or longer Unrealized Losses	30	31
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	12	5
Dollar-denominated | Banks/financial institutions
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	105	3
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	58	3
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,147	292
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	786	274
12 months or longer Unrealized Losses	361	18
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	47	0
Dollar-denominated | Other corporate
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	1,201	53
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	785	8
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	10,529	1,365
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	8,636	458
12 months or longer Unrealized Losses	1,893	907
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	416	45
Yen-denominated | Japan government and agencies
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	1,724	61
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	580	3
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	8,856	2,868
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	3,733	445
12 months or longer Unrealized Losses	5,123	2,423
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	1,144	58
Yen-denominated | Municipalities
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	61	5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	26	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	286	187
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	150	53
12 months or longer Unrealized Losses	136	134
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	35	5
Yen-denominated | Mortgage- and asset-backed securities
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	12	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	6	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	62	33
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	38	0
12 months or longer Unrealized Losses	24	33
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	6	1
Yen-denominated | Public utilities
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	108	2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	61	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	880	26
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	576	0
12 months or longer Unrealized Losses	304	26
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	47	2
Yen-denominated | Sovereign and supranational
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	4
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	71
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	34
12 months or longer Unrealized Losses	37
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	1
Yen-denominated | Banks/financial institutions
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	531	72
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	174	16
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	3,957	2,074
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,760	1,011
12 months or longer Unrealized Losses	2,197	1,063
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	357	56
Yen-denominated | Other corporate
Investments, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	408	26
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	273	4
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	2,090	541
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,507	274
12 months or longer Unrealized Losses	583	267
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ 135	$ 22