Consolidated Statement of Shareholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Balance at beginning of period at Dec. 31, 2012	$ 221,728	$ 167,039	$ 69,158	$ 654	$ (15,123)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	9,943		9,943
Other comprehensive loss, net of tax	(10,802)			(10,802)
Common stock cash dividends declared	(2,807)		(2,807)
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	55	55
Reissuance of treasury stock for deferred compensation plan	142				142
Purchase of treasury stock	(86)				(86)
Common shares issued under dividend reinvestment plan	207	207
Common shares issued under Board of Directors' compensation plan	84	(20)			104
Stock based compensation expense	683	683
Balance at end of period at Jun. 30, 2013	$ 219,147	$ 167,964	$ 76,294	$ (10,148)	$ (14,963)