Investments, Amortized Cost, Gross Unrealized Gains and Losses and Fair Value of Investment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Securities [Abstract]
Amortized cost	$ 243,842	$ 242,242
Gross unrealized gains	3,446	752
Gross unrealized losses	(261)	(1,984)
Fair value	247,027	241,010
U.S. Agency Securities [Member]
Debt Securities [Abstract]
Amortized cost	86,514	106,516
Gross unrealized gains	1,622	509
Gross unrealized losses	(97)	(640)
Fair value	88,039	106,385
U.S. Treasury Securities [Member]
Debt Securities [Abstract]
Amortized cost	32,347	33,813
Gross unrealized gains	266	0
Gross unrealized losses	(1)	(455)
Fair value	32,612	33,358
Obligations of State and Political Subdivisions [Member]
Debt Securities [Abstract]
Amortized cost	60,149	52,074
Gross unrealized gains	984	150
Gross unrealized losses	(17)	(177)
Fair value	61,116	52,047
Corporate Obligations [Member]
Debt Securities [Abstract]
Amortized cost	3,000	3,000
Gross unrealized gains	76	34
Gross unrealized losses	0	0
Fair value	3,076	3,034
Mortgage-backed Securities in Government Sponsored Entities [Member]
Debt Securities [Abstract]
Amortized cost	61,832	46,839
Gross unrealized gains	498	59
Gross unrealized losses	(146)	(712)
Fair value	$ 62,184	$ 46,186

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).

+ References

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-Publisher FASB
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