FAIR VALUE MEASUREMENTS - Fair Value Measurement Inputs and Valuation Techniques (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	$ 79,431	$ 98,696
Equity securities	1,149	1,603
Assets, fair value	89,006	108,012
Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	1,607	1,298
Equity securities	190	173
Assets, fair value	1,797	1,471
Net asset value valuation technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Equity securities	190	173
Mortgage- and asset-backed securities
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	1,952	1,246
Mortgage- and asset-backed securities \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	311	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	311	291
Public utilities
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	7,957	10,051
Public utilities \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	537	493
Public utilities \| Discounted cash flow technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	537	493
Sovereign and supranational
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	913	1,115
Sovereign and supranational \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	36	43
Sovereign and supranational \| Discounted cash flow technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	36	43
Banks/financial institutions
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	9,625	11,591
Banks/financial institutions \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	91	45
Banks/financial institutions \| Consensus pricing valuation technique \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	91	45
Other corporate
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	30,557	37,837
Other corporate \| Level 3
Fair Value Measurement Inputs and Valuation Techniques
Available for sale, fixed maturity securities	$ 632	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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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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No definition available.

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