Consolidated Statements Of Changes In Shareholders' Equity - USD ($) $ in Thousands	Common Stocks [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2015	$ 4,659	$ 38,778	$ 78,517	$ (3,722)	$ (6,856)	$ 111,376
Net income			8,087			8,087
Other comprehensive income (loss)				(493)		(493)
Cash dividends declared			(3,523)			(3,523)
Acquisition of treasury stock					(795)	(795)
Treasury shares issued under employee stock purchase plan		4			16	20
Treasury shares issued under dividend reinvestment plan		296			822	1,118
Common stock issued under dividend reinvestment plan	25	528				553
Common stock issued under incentive stock option plan	4	58				62
Stock option compensation expense		88				88
Balance at Dec. 31, 2016	4,688	39,752	83,081	(4,215)	(6,813)	116,493
Net income			2,176			2,176
Other comprehensive income (loss)				(821)		(821)
Cash dividends declared			(4,031)			(4,031)
Treasury shares issued under employee stock purchase plan		32			125	157
Treasury shares issued under dividend reinvestment plan		434			557	991
Common stock issued under incentive stock option plan	1	17				18
Revaluation of net deferred tax assets			992	(992)
Stock option compensation expense		161				161
Balance at Dec. 31, 2017	4,689	40,396	82,218	(6,028)	(6,131)	115,144
Cumulative adjustment for fair value of equity securities			201	(201)
Net income			6,125			6,125
Other comprehensive income (loss)				(151)		(151)
Cash dividends declared			(4,598)			(4,598)
Acquisition of treasury stock					(88)	(88)
Treasury shares issued under employee stock purchase plan		38			60	98
Treasury shares issued under dividend reinvestment plan		659			758	1,417
Common stock issued under incentive stock option plan	12	252				264
Stock option compensation expense		185				185
Balance at Dec. 31, 2018	$ 4,701	$ 41,530	$ 83,946	$ (6,380)	$ (5,401)	$ 118,396