FAIR VALUE MEASUREMENTS (Schedule of Maturities on Debt Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Total maturities of fixed-income securities	$ 4,209	$ 3,703
Fixed-income securities
Debt Securities, Available-for-sale [Line Items]
Less than 1 year	50
1–5 years	475
5–10 years	403
More than 10 years	831
Total maturities of fixed-income securities	$ 1,759	$ 1,590

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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