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, 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			3,502			3,502
Other comprehensive income (loss)				(781)		(781)
Cash dividends declared			(1,045)			(1,045)
Acquisition of treasury stock					(88)	(88)
Treasury shares issued under employee stock purchase plan		2			4	6
Treasury shares issued under dividend reinvestment plan		97			109	206
Common stock issued under incentive stock option plan	7	142				149
Stock option compensation expense		31				31
Balance at Mar. 31, 2018	4,696	40,668	84,876	(7,010)	(6,106)	117,124
Balance at Dec. 31, 2018	4,701	41,530	83,946	(6,380)	(5,401)	118,396
Net income			3,237			3,237
Other comprehensive income (loss)				1,099		1,099
Cash dividends declared			(1,192)			(1,192)
Acquisition of treasury stock					(560)	(560)
Treasury shares issued under employee stock purchase plan		2			3	5
Treasury shares issued under dividend reinvestment plan		161			190	351
Common stock issued under incentive stock option plan	7	148				155
Balance at Mar. 31, 2019	$ 4,708	$ 41,841	$ 85,991	$ (5,281)	$ (5,768)	$ 121,491