Investments, Gross Unrealized Losses and Fair Value and Net Unrealized Gains (Losses) (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($) Security	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) Security	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	$ 0		$ 0		$ 25,180
Twelve months or greater, Fair value	59,077		59,077		126,094
Total, Fair value	59,077		59,077		151,274
Less than twelve months, Gross unrealized losses	0		0		(76)
Twelve months or greater, Gross unrealized losses	(218)		(218)		(1,908)
Total, Gross Unrealized Losses	$ (218)		$ (218)		(1,984)
Number of securities owned with fair value less than cost \| Security	41		41
Proceeds from sale of securities available-for-sale	$ 0	$ 0	$ 0	$ 0
Equity securities [Abstract]
Net gains (losses) recognized in equity securities during the period	30	7	41	13
Less: Net gains realized on the sale of equity securities during the period	0	0	0	0
Net unrealized gains (losses)	30	$ 7	41	$ 13
Investment securities pledged as collateral	227,300		227,300		221,200
U.S. Agency Securities [Member]
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	0		0		5,981
Twelve months or greater, Fair value	36,648		36,648		52,673
Total, Fair value	36,648		36,648		58,654
Less than twelve months, Gross unrealized losses	0		0		(5)
Twelve months or greater, Gross unrealized losses	(106)		(106)		(635)
Total, Gross Unrealized Losses	(106)		(106)		(640)
U.S. Treasury Securities [Member]
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	0		0		4,948
Twelve months or greater, Fair value	1,987		1,987		28,410
Total, Fair value	1,987		1,987		33,358
Less than twelve months, Gross unrealized losses	0		0		(31)
Twelve months or greater, Gross unrealized losses	(1)		(1)		(424)
Total, Gross Unrealized Losses	(1)		(1)		(455)
Obligations of State and Political Subdivisions [Member]
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	0		0		8,979
Twelve months or greater, Fair value	1,843		1,843		12,441
Total, Fair value	1,843		1,843		21,420
Less than twelve months, Gross unrealized losses	0		0		(22)
Twelve months or greater, Gross unrealized losses	(7)		(7)		(155)
Total, Gross Unrealized Losses	(7)		(7)		(177)
Mortgage-backed Securities in Government Sponsored Entities [Member]
Available-for-sale, Debt Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than twelve months, Fair value	0		0		5,272
Twelve months or greater, Fair value	18,381		18,381		32,570
Total, Fair value	18,381		18,381		37,842
Less than twelve months, Gross unrealized losses	0		0		(18)
Twelve months or greater, Gross unrealized losses	(104)		(104)		(694)
Total, Gross Unrealized Losses	$ (104)		$ (104)		$ (712)

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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