Stockholders' Equity and Earnings per Share, Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Stockholders Equity Note [Abstract]
Beginning Balance			$ 96,388	$ 93,990
Ending Balance	$ 99,575	$ 97,641	99,575	97,641
Other comprehensive income, pretax [Abstract]
Unrealized holding gains (losses) arising during the period, pretax	(1,017)	89	(3,385)	2,394
Reclassification adjustment for gains recognized in income, pretax	0	(2)	(120)	(89)
Total change in accumulated other comprehensive loss, net, pretax	(1,017)	87	(3,505)	2,305
Other Comprehensive Income, Tax Effect [Abstract]
Unrealized holding gains (losses) arising during the period, tax effect	(214)	30	(711)	814
Reclassification adjustment for gains recognized in income, tax effect	0	0	(25)	(30)
Total change in accumulated other comprehensive loss, net, tax effect	(214)	30	(736)	784
Other Comprehensive Income, Net of Tax [Abstract]
Unrealized holding gains (losses) arising during the period, net of tax	(803)	59	(2,674)	1,580
Reclassification adjustment for gains recognized in income, net of tax	0	(2)	(95)	(59)
Other comprehensive income (loss), net of tax	(803)	57	(2,769)	1,521
ASU 2018-02 [Member]
Stockholders Equity Note [Abstract]
Reclassification of the income tax effects of the Tax Cuts and Jobs Act from AOCI					$ 0
ASU 2016-01 [Member]
Stockholders Equity Note [Abstract]
Reclassification of net unrealized gains on equity securities from AOCI					0
Unrealized Gains (Losses) on Available-for-Sale Securities [Member]
Stockholders Equity Note [Abstract]
Beginning Balance	(2,889)	(275)	(707)	(1,739)
Net other comprehensive income (loss)	(803)	57	(2,769)	1,521
Ending Balance	(3,692)	(218)	(3,692)	(218)
Unrealized Gains (Losses) on Available-for-Sale Securities [Member] | ASU 2018-02 [Member]
Stockholders Equity Note [Abstract]
Reclassification of the income tax effects of the Tax Cuts and Jobs Act from AOCI					(139)
Unrealized Gains (Losses) on Available-for-Sale Securities [Member] | ASU 2016-01 [Member]
Stockholders Equity Note [Abstract]
Reclassification of net unrealized gains on equity securities from AOCI					(77)
Defined Benefit Pension Plans [Member]
Stockholders Equity Note [Abstract]
Beginning Balance	0	(2,469)	0	(2,469)
Net other comprehensive income (loss)	0	0	0	0
Ending Balance	0	(2,469)	0	(2,469)
Defined Benefit Pension Plans [Member] | ASU 2018-02 [Member]
Stockholders Equity Note [Abstract]
Reclassification of the income tax effects of the Tax Cuts and Jobs Act from AOCI					0
Defined Benefit Pension Plans [Member] | ASU 2016-01 [Member]
Stockholders Equity Note [Abstract]
Reclassification of net unrealized gains on equity securities from AOCI					0
Accumulated Other Comprehensive Loss [Member]
Stockholders Equity Note [Abstract]
Beginning Balance	(2,889)	(2,744)	(707)	(4,208)
Net other comprehensive income (loss)	(803)	57	(2,769)	1,521
Ending Balance	$ (3,692)	$ (2,687)	(3,692)	(2,687)
Other Comprehensive Income, Net of Tax [Abstract]
Other comprehensive income (loss), net of tax			$ (2,769)	$ 1,521
Accumulated Other Comprehensive Loss [Member] | ASU 2018-02 [Member]
Stockholders Equity Note [Abstract]
Reclassification of the income tax effects of the Tax Cuts and Jobs Act from AOCI					(139)
Accumulated Other Comprehensive Loss [Member] | ASU 2016-01 [Member]
Stockholders Equity Note [Abstract]
Reclassification of net unrealized gains on equity securities from AOCI					$ (77)