Investment Securities - Available for sale (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Marketable securities
Amortized Cost	$ 125,158	$ 103,334
Gross Unrealized Gains	3,020	1,156
Gross Unrealized Losses	167	169
Fair Value	128,011	104,321
Obligations of U.S. Government agencies
Debt securities
Amortized Cost	5,753	10,186
Gross Unrealized Gains	172	162
Gross Unrealized Losses	7	36
Fair Value	5,918	10,312
Obligations of States and political subdivisions
Debt securities
Amortized Cost	36,787	33,885
Gross Unrealized Gains	1,700	716
Gross Unrealized Losses		43
Fair Value	38,487	34,558
Mortgage-backed securities
Debt securities
Amortized Cost	79,132	56,275
Gross Unrealized Gains	1,074	236
Gross Unrealized Losses	160	90
Fair Value	80,046	56,421
Subordinated debt investments
Debt securities
Amortized Cost	3,486	2,988
Gross Unrealized Gains	74	42
Fair Value	$ 3,560	$ 3,030

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Represents the amount of unrealized gain on investment in marketable security.

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Represents the amount of unrealized loss on investment in marketable security.

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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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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Amount of investment in marketable security.

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