Accumulated Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance			$ 123,268
Other comprehensive income (loss) before reclassifications (net of tax)	$ (190)	$ (692)	288	$ 1,609
Amounts reclassified from accumulated other comprehensive income (loss) (net of tax)	31	40	(24)	17
Other comprehensive income (loss), net of tax	(159)	(652)	264	1,626
Ending Balance	129,882		129,882
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(969)	2,042	(1,392)	(236)
Ending Balance	(1,128)	1,390	(1,128)	1,390
Unrealized Gain (Loss) on Available for Sale Securities [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	1,655	4,403	1,306	2,204
Other comprehensive income (loss) before reclassifications (net of tax)	(190)	(692)	288	1,609
Amounts reclassified from accumulated other comprehensive income (loss) (net of tax)	(6)	0	(135)	(102)
Other comprehensive income (loss), net of tax	(196)	(692)	153	1,507
Ending Balance	1,459	3,711	1,459	3,711
Defined Benefit Pension Items [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(2,624)	(2,361)	(2,698)	(2,440)
Other comprehensive income (loss) before reclassifications (net of tax)	0	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss) (net of tax)	37	40	111	119
Other comprehensive income (loss), net of tax	37	40	111	119
Ending Balance	$ (2,587)	$ (2,321)	$ (2,587)	$ (2,321)