Securities Available For Sale - Amortized Cost to Approximate Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Available-for-sale securities:
Amortized Cost	$ 337,854	$ 289,664
Gross Unrealized Gains	1,200	618
Gross Unrealized Losses	1	39
Fair Value of available for sale securities	339,053	290,243
Treasury notes.
Available-for-sale securities:
Amortized Cost	1,994	4,744
Gross Unrealized Gains	49	21
Fair Value of available for sale securities	2,043	4,765
Federal agencies
Available-for-sale securities:
Amortized Cost	306,152	244,986
Gross Unrealized Gains	423	24
Gross Unrealized Losses		37
Fair Value of available for sale securities	306,575	244,973
Municipals
Available-for-sale securities:
Amortized Cost	5,566	5,577
Gross Unrealized Gains	385	360
Fair Value of available for sale securities	5,951	5,937
Mortgage-backed - Government-sponsored entity (GSE) - residential
Available-for-sale securities:
Amortized Cost	24,142	34,357
Gross Unrealized Gains	343	213
Gross Unrealized Losses	1	2
Fair Value of available for sale securities	$ 24,484	$ 34,568

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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-Publisher FASB
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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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