INVESTMENTS (Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity) (Details) $ in Thousands	Mar. 31, 2021 USD ($)
Amortized Cost
One year or less	$ 23,049
Over one through five years	119,663
Over five through ten years	129,560
Over ten years	133,901
Amortized Cost	406,173
Fair Value
One year or less	23,442
Over one through five years	123,434
Over five through ten years	128,609
Over ten years	136,233
Fair Value	$ 411,718

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 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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