Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	$ 56,666	$ 60,007	$ 56,142
Reclassification of net unrealized gains on equity securities from accumulated other comprehensive income (loss)	239	62	662
Other comprehensive income (loss) before reclassifications		1,664	(910)
Balance	57,698	64,106	57,698
Gains (Losses) on Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance		172	37
Other comprehensive income (loss) before reclassifications		(228)	189
Balance	226	(56)	226
Unrealized Gains (Losses) on Available for Sale Securities [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance		(850)	(37)
Reclassification of net unrealized gains on equity securities from accumulated other comprehensive income (loss)			(10)
Other comprehensive income (loss) before reclassifications		1,892	(1,099)
Balance	(1,146)	1,042	(1,146)
Supplemental Executive Retirement Plans [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance		140	125
Balance	125	140	125
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	(582)	(538)	125
Reclassification of net unrealized gains on equity securities from accumulated other comprehensive income (loss)			(10)
Balance	$ (795)	$ 1,126	$ (795)