INVESTMENTS (Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity) (Details) $ in Thousands	Jun. 30, 2020 USD ($)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
One year or less	$ 36,092
Over one through five years	186,332
Over five through ten years	138,456
Over ten years	176,016
Amortized Cost	536,896
Available-for-sale Securities, Debt maturities, Fair value:
One year or less	36,331
Over one through five years	193,816
Over five through ten years	145,727
Over ten years	180,087
Fair Value	$ 555,961

Amortized cost 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 fiscal year through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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