INVESTMENT SECURITIES - Contractual maturities, Available for sale (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Available for Sale, Amortized Cost
Due after one year through five years	$ 9,533
Due after five years through ten years	78,612
Due after ten years	190,487
Total, Amortized Cost	278,632
Available for Sale, Estimated Fair Value
Due after one year through five years	9,610
Due after five years through ten years	78,730
Due after ten years	189,884
Total, Estimated Fair Value	$ 278,224

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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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 second through fifth 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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