FAIR VALUE MEASUREMENTS (Schedule of Maturities on Debt Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Total maturities of fixed-income securities	$ 4,581	$ 4,209
Fixed-income securities
Debt Securities, Available-for-sale [Line Items]
Less than 1 year	97
1–5 years	495
5–10 years	480
More than 10 years	952
Total maturities of fixed-income securities	$ 2,024	$ 1,759

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