FAIR VALUE MEASUREMENTS - Fair Value Measurement Inputs and Valuation Techniques (Detail) $ in Millions		Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		$ 64,121	$ 65,269
Equity securities		887	796
Total assets		72,805	74,133
Level 3
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		3,357	2,067
Equity securities		160	157
Total assets		3,517	2,224
Adjusted cost | Level 3 | Private financials
Fair Value Measurement Inputs and Valuation Technique
Equity securities		160	157
Mortgage- and asset-backed securities
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		4,366	3,563
Mortgage- and asset-backed securities | Level 3
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		2,294	1,156
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3 | Offered quotes
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		$ 2,294	$ 1,156
Mortgage- and asset-backed securities | Lower Limit | Consensus pricing valuation technique | Level 3 | Offered quotes
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale, measurement input	[1]	88.75	84.08
Mortgage- and asset-backed securities | Upper Limit | Consensus pricing valuation technique | Level 3 | Offered quotes
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale, measurement input	[1]	106.70	104.60
Mortgage- and asset-backed securities | Weighted Average | Consensus pricing valuation technique | Level 3 | Offered quotes
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale, measurement input	[1]	100.42	99.07
Public utilities
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		$ 7,174	$ 7,045
Public utilities | Level 3
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		876	647
Public utilities | Discounted cash flow technique | Level 3 | Credit spreads
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		$ 876	$ 647
Public utilities | Lower Limit | Discounted cash flow technique | Level 3 | Credit spreads
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0100	0.0100
Public utilities | Upper Limit | Discounted cash flow technique | Level 3 | Credit spreads
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0391	0.0375
Public utilities | Weighted Average | Discounted cash flow technique | Level 3 | Credit spreads
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0163	0.0162
Sovereign and supranational
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		$ 402	$ 416
Sovereign and supranational | Level 3
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		19	23
Sovereign and supranational | Consensus pricing valuation technique | Level 3 | Offered quotes
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		19	23
Banks/financial institutions
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		9,244	8,956
Banks/financial institutions | Level 3
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		9	10
Banks/financial institutions | Adjusted cost | Level 3 | Private financials
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		9	10
Other corporate
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		26,398	25,409
Other corporate | Level 3
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		159	231
Other corporate | Discounted cash flow technique | Level 3 | Credit spreads
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale		$ 159	$ 231
Other corporate | Lower Limit | Discounted cash flow technique | Level 3 | Credit spreads
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0075	0.0091
Other corporate | Upper Limit | Discounted cash flow technique | Level 3 | Credit spreads
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0384	0.0294
Other corporate | Weighted Average | Discounted cash flow technique | Level 3 | Credit spreads
Fair Value Measurement Inputs and Valuation Technique
Fixed maturity securities, available-for-sale, measurement input	[2]	0.0217	0.0173

[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