FAIR VALUE MEASUREMENTS (Schedule of Maturities on Debt Securities) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Total fair value	$ 4,282	$ 4,209
Fixed-income securities
Debt Securities, Available-for-sale [Line Items]
Less than 1 year	32
1–5 years	501
5–10 years	427
More than 10 years	805
Total fair value	$ 1,765	$ 1,759

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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