Condensed Consolidated Statements of Changes in Equity (USD $) In Thousands, unless otherwise specified	Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Total
Balance at Dec. 31, 2012	$ 118,737	$ 341,586	$ 1,165,952	$ (1,248,377)	$ (49,734)	$ 328,164
Increase (Decrease) in Stockholders' Equity
Exercise of stock options and release of unvested shares	450	469		(407)		512
Net tax effect of stock options exercised and release of unvested shares		(2,606)				(2,606)
Stock-based compensation		5,744				5,744
Dividends paid ($0.255 and $0.255 per share for nine months ended September 30, 2014 and twelve months ended December 31, 2013, respectively)			(16,121)			(16,121)
Treasury stock issued		(98)		135		37
Purchase of treasury stock				(1,662)		(1,662)
Net income (loss)			13,370			13,370
Other comprehensive income (loss)					21,616	21,616
Balance at Dec. 31, 2013	119,187	345,095	1,163,201	(1,250,311)	(28,118)	349,054
Increase (Decrease) in Stockholders' Equity
Exercise of stock options and release of unvested shares	411	48		(750)		(291)
Net tax effect of stock options exercised and release of unvested shares		(1,277)				(1,277)
Stock-based compensation		3,552				3,552
Dividends paid ($0.255 and $0.255 per share for nine months ended September 30, 2014 and twelve months ended December 31, 2013, respectively)			(16,154)			(16,154)
Treasury stock issued		(767)		1,051		284
Purchase of treasury stock				(5,362)		(5,362)
Net income (loss)			13,902			13,902
Other comprehensive income (loss)					873	873
Balance at Sep. 30, 2014	$ 119,598	$ 346,651	$ 1,160,949	$ (1,255,372)	$ (27,245)	$ 344,581