FAIR VALUE MEASUREMENTS - Fair Value Measurement Inputs and Valuation Techniques (Details) $ in Millions		Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		$ 66,259	$ 73,290
Equity securities		728	1,088
Total assets		76,743	80,325
Level 3
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		2,056	1,781
Equity securities		157	248
Total assets		2,213	2,029
Adjusted cost valuation technique | Level 3 | Private Financials
Fair Value Measurement Inputs and Valuation Techniques
Equity securities		157	248
Municipalities
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		2,083	2,298
Municipalities | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		0	0
Mortgage- and asset-backed securities
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		3,703	3,086
Mortgage- and asset-backed securities | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		1,213	772
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3 | Offered Quotes
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		$ 1,213	$ 772
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3 | Lower Limit | Offered Quotes
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[1]	85.46	84.81
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3 | Upper Limit | Offered Quotes
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[1]	104.49	105.89
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3 | Weighted Average | Offered Quotes
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[1]	98.74	99.39
Public utilities
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		$ 6,826	$ 7,592
Public utilities | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		365	253
Public utilities | Consensus pricing valuation technique | Level 3 | Offered Quotes
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale			$ 253
Public utilities | Consensus pricing valuation technique | Level 3 | Lower Limit | Offered Quotes
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[1]		94.34
Public utilities | Consensus pricing valuation technique | Level 3 | Upper Limit | Offered Quotes
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[1]		102.99
Public utilities | Consensus pricing valuation technique | Level 3 | Weighted Average | Offered Quotes
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[1]		96.46
Public utilities | Discounted cash flow technique | Level 3 | Credit Spreads
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		$ 365
Public utilities | Discounted cash flow technique | Level 3 | Lower Limit | Credit Spreads
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0175
Public utilities | Discounted cash flow technique | Level 3 | Upper Limit | Credit Spreads
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0225
Public utilities | Discounted cash flow technique | Level 3 | Weighted Average | Credit Spreads
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0209
Sovereign and supranational
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		$ 460	$ 537
Sovereign and supranational | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		25	30
Sovereign and supranational | Consensus pricing valuation technique | Level 3 | Offered Quotes
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		25	30
Banks/financial institutions
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		8,699	8,835
Banks/financial institutions | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		69	78
Banks/financial institutions | Discounted cash flow technique | Level 3 | Credit Spreads
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		69	78
Other corporate
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		26,207	28,342
Other corporate | Level 3
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		384	648
Other corporate | Discounted cash flow technique | Level 3 | Credit Spreads
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale		$ 384	$ 648
Other corporate | Discounted cash flow technique | Level 3 | Lower Limit | Credit Spreads
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0089	0.0069
Other corporate | Discounted cash flow technique | Level 3 | Upper Limit | Credit Spreads
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0363	0.0423
Other corporate | Discounted cash flow technique | Level 3 | Weighted Average | Credit Spreads
Fair Value Measurement Inputs and Valuation Techniques
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0224	0.0206

[1] Represents prices for securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques.

[2] Actual or equivalent credit spreads in basis points.