Investment Securities - Amortized cost and estimated fair value (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Amortized Cost
Due within one year or less	$ 14,799
Due after one year through five years	25,193
Due after five years through ten years	83,987
Due after 10 years	183,785
Total investment securities available-for-sale	307,764
Fair Value
Due within one year or less	14,807
Due after one year through five years	25,315
Due after five years through ten years	84,965
Due after 10 years	185,263
Total investment securities available-for-sale	$ 310,350

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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