FAIR VALUE MEASUREMENTS - Fair Value Measurement Inputs and Valuation Techniques (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	$ 73,643	$ 98,696
Equity securities	1,064	1,603
Assets, fair value	82,379	108,012
Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	1,620	1,298
Equity securities	197	173
Assets, fair value	1,817	1,471
Net asset value valuation technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Equity securities	197	173
Municipalities
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	2,276	3,036
Municipalities \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	0	0
Mortgage- and asset-backed securities
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	2,009	1,246
Mortgage- and asset-backed securities \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	310	291
Mortgage- and asset-backed securities \| Consensus pricing valuation technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	310	291
Public utilities
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	7,350	10,051
Public utilities \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	507	493
Public utilities \| Discounted cash flow technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	507	493
Sovereign and supranational
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	862	1,115
Sovereign and supranational \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	34	43
Sovereign and supranational \| Discounted cash flow technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	34	43
Banks/financial institutions
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	9,031	11,591
Banks/financial institutions \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	148	45
Banks/financial institutions \| Consensus pricing valuation technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	148	45
Other corporate
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	28,205	37,837
Other corporate \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	$ 621	426
Other corporate \| Discounted cash flow technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities		$ 426

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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No definition available.

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