Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	$ 56,142	$ 54,451	$ 52,633
Reclassification of the income tax effect of the Tax Act from accumulated other comprehensive income (loss)		21
Reclassification of net unrealized gains on equity securities from accumulated other comprehensive income (loss)	662
Other comprehensive income (loss) before reclassifications	(673)	841	(277)
Balance	60,007	56,142	54,451
Gains (Losses) on Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	37	17	(190)
Reclassification of the income tax effect of the Tax Act from accumulated other comprehensive income (loss)		6
Other comprehensive income (loss) before reclassifications	135	14	207
Balance	172	37	17
Unrealized Gains (Losses) on Available for Sale Securities [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	(37)	(765)	(229)
Reclassification of the income tax effect of the Tax Act from accumulated other comprehensive income (loss)		(7)
Reclassification of net unrealized gains on equity securities from accumulated other comprehensive income (loss)	10
Other comprehensive income (loss) before reclassifications	(823)	735	(536)
Balance	(850)	(37)	(765)
Supplemental Executive Retirement Plans [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	125	11	(41)
Reclassification of the income tax effect of the Tax Act from accumulated other comprehensive income (loss)		22
Other comprehensive income (loss) before reclassifications	15	92	52
Balance	140	125	11
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	125	(737)	(460)
Reclassification of net unrealized gains on equity securities from accumulated other comprehensive income (loss)	10
Balance	$ (538)	$ 125	$ (737)