Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	$ 149,383	$ 143,717	$ 138,488	$ 128,141	$ 123,104	$ 118,105	$ 138,488	$ 118,105
Other comprehensive (loss) income before reclassification	(15)			(216)			139	(262)
Less amounts reclassified from accumulated other comprehensive income (loss)	0			(13)			50	112
Total other comprehensive income (loss), net of tax	(15)	154	(50)	(203)	(5)	(166)	89	(374)
Ending Balance	154,884	149,383	143,717	133,067	128,141	123,104	154,884	133,067
Net unrealized (losses) gains on securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	(6)		(721)	(995)		(335)	(721)	(335)
Other comprehensive (loss) income before reclassification	111			(211)			982	(865)
Less amounts reclassified from accumulated other comprehensive income (loss)	15			2			171	8
Total other comprehensive income (loss), net of tax	96			(213)			811	(873)
Ending Balance	90	(6)		(1,208)	(995)		90	(1,208)
Adjustments related to defined benefit plan
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	(325)		(431)	(460)		(341)	(431)	(341)
Other comprehensive (loss) income before reclassification	0			0			0	0
Less amounts reclassified from accumulated other comprehensive income (loss)	(15)			(15)			(121)	104
Total other comprehensive income (loss), net of tax	15			15			121	(104)
Ending Balance	(310)	(325)		(445)	(460)		(310)	(445)
Net unrealized gains (losses) from cash flow hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	313		1,030	1,490		882	1,030	882
Other comprehensive (loss) income before reclassification	(126)			(5)			(843)	603
Less amounts reclassified from accumulated other comprehensive income (loss)	0			0			0	0
Total other comprehensive income (loss), net of tax	(126)			(5)			(843)	603
Ending Balance	187	313		1,485	1,490		187	1,485
Accumulated other comprehensive income (loss)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	(53)	(207)	(157)		30	206	(157)	206
Total other comprehensive income (loss), net of tax	(15)	154	(50)	(203)	(5)	(166)
Ending Balance	(68)	(53)	(207)	(203)		30	(68)	(203)
Accounting Standards Update 2016-01 and 2018-02
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Reclassification to retained earnings				35				35
Accounting Standards Update 2016-01 and 2018-02 \| Accumulated other comprehensive income (loss)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	(18)		$ (122)	35		$ 206	(122)	206
Ending Balance	$ (33)	$ (18)		$ (168)	$ 35		$ (33)	$ (168)

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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