Consolidated Statements Of Changes In Shareholders' Equity (USD $) In Thousands	Common Stock [Member]	Capital in Excess of Par Value [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Deferred Compensation Arrangements [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balance at Dec. 31, 2011	$ 67	$ 36,544	$ 79,393	$ (15,817)	$ 6,248	$ 3,102	$ 109,537
Net income	0	0	15,194	0	0	0	15,194
Dividends paid ($1.12 per share)	0	0	(7,007)	0	0	0	(7,007)
Sale of treasury stock	0	2	0	16	0	0	18
Purchase of treasury stock							0
Distribution of stock under deferred compensation arrangements	0	0	0	386	(386)	0	0
Shares granted under stock plans and deferral of director fees, including excess tax benefit	0	41	0	380	90	0	511
Share-based compensation expense	0	72	0	0	100	0	172
Dividend reinvestment plan	0	83	0	249	351	0	683
Other comprehensive income (loss)	0	0	0	0	0	(887)	(887)
Balance at Dec. 31, 2012	67	36,742	87,580	(14,786)	6,403	2,215	118,221
Net income	0	0	15,131	0	0	0	15,131
Dividends paid ($1.12 per share)	0	0	(7,054)	0	0	0	(7,054)
Sale of treasury stock	0	3	0	12	0	0	15
Purchase of treasury stock							0
Distribution of stock under deferred compensation arrangements	0	0	0	450	(450)	0	0
Shares granted under stock plans and deferral of director fees, including excess tax benefit	0	223	0	140	61	0	424
Share-based compensation expense	0	27	0	0	160	0	187
Dividend reinvestment plan	0	134	0	141	347	0	622
Other comprehensive income (loss)	0	0	0	0	0	(7,935)	(7,935)
Balance at Dec. 31, 2013	67	37,129	95,657	(14,043)	6,521	(5,720)	119,611
Net income	0	0	12,125	0	0	0	12,125
Dividends paid ($1.12 per share)	0	0	(7,085)	0	0	0	(7,085)
Sale of treasury stock							0
Purchase of treasury stock	0	0	0	(82)	0	0	(82)
Distribution of stock under deferred compensation arrangements	0	0	0	553	(553)	0	0
Shares granted under stock plans and deferral of director fees, including excess tax benefit	0	275	0	164	22	0	461
Share-based compensation expense	0	0	0	(122)	241	0	119
Dividend reinvestment plan	0	0	0	(335)	335	0	0
Other comprehensive income (loss)	0	0	0	0	0	672	672
Balance at Dec. 31, 2014	$ 67	$ 37,404	$ 100,697	$ (13,865)	$ 6,566	$ (5,048)	$ 125,821