Securities - Amortized Cost to Approximate Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale securities:
Amortized Cost	$ 289,664	$ 331,529
Gross Unrealized Gains	618	624
Gross Unrealized Losses	39	1,082
Fair Value of available for sale securities	290,243	331,071
Treasury notes.
Available-for-sale securities:
Amortized Cost	4,744	11,928
Gross Unrealized Gains	21	26
Gross Unrealized Losses		13
Fair Value of available for sale securities	4,765	11,941
Federal agencies
Available-for-sale securities:
Amortized Cost	244,986	237,894
Gross Unrealized Gains	24	8
Gross Unrealized Losses	37	972
Fair Value of available for sale securities	244,973	236,930
Municipals
Available-for-sale securities:
Amortized Cost	5,577	21,014
Gross Unrealized Gains	360	336
Gross Unrealized Losses		18
Fair Value of available for sale securities	5,937	21,332
Mortgage-backed - Government-sponsored entity (GSE) - residential
Available-for-sale securities:
Amortized Cost	34,357	60,693
Gross Unrealized Gains	213	254
Gross Unrealized Losses	2	79
Fair Value of available for sale securities	$ 34,568	$ 60,868

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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Amount, before tax, of unrealized loss 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 debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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