Investment Securities (Amortized Cost and Fair Value of Debt Securities by Contractual Maturity Date) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Investment Securities [Abstract]
Amortized cost: Due after one year through five years	$ 6,913
Amortized cost: Due after five years through ten years	55,874
Amortized cost: Due after ten years	174,744
Amortized cost: MBS - GSE residential	143,557
Amortized cost: Total available-for-sale debt securities	381,088	$ 180,557
Fair value: Due after one year through five years	7,339
Fair value: Due after five years through ten years	56,090
Fair value: Due after ten years	181,731
Fair value: MBS - GSE residential	147,260
Fair value: Total available-for-sale debt securities	$ 392,420	$ 185,117

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
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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 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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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 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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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 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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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 second through fifth 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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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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