Consolidated Statements of Shareholders’ Equity (USD $) In Thousands	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balance at Dec. 31, 2009	$ 118,212	$ 141,400		$ 259,612
Net income (loss)		2,132		2,132
Payment of dividends		(870)		(870)
Exercise of stock options and employee stock purchases	137			137
Stock-based compensation	627			627
Balance at Dec. 31, 2010	118,976	142,662		261,638
Net income (loss)		24,970		24,970
Payment of dividends		(872)		(872)
Exercise of stock options and employee stock purchases	34			34
Stock-based compensation	806			806
Balance at Dec. 31, 2011	119,816	166,760		286,576
Net income (loss)		2,277		2,277
Payment of dividends		(873)		(873)
Exercise of stock options and employee stock purchases	505			505
Stock-based compensation	1,951			1,951
Change in fair value of interest rate hedge			(579)	(579)
Balance at Dec. 31, 2012	$ 122,272	$ 168,164	$ (579)	$ 289,857