Consolidated Statements of Changes in Stockholders' Equity (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Treasury Stock [Member]
Balance at beginning of period at Dec. 31, 2011		$ 686	$ 372,212	$ (4,050)	$ 89,135	$ (224,868)
Shares at beginning of period at Dec. 31, 2011		68,566				30,644
Issuance for stock-based compensation and dividends, net of forfeitures		(105)
Exercise of stock options	70	70
Issuance for stock-based compensation and dividends, net of forfeitures		(1)	36
Exercise of stock options		0	736
Income tax benefit from stock-based compensation			1,201
Stock-based compensation expense			26,243
Employee stock purchase plan	647		260			387
Pension and post-retirement plans, net of tax of $394, $1,919 and $854, respectively	1,337			1,337
Net income (loss)	(13,703)				(13,703)
Dividends, net of forfeitures ($0.41, $0.10 and $1.00 per share, respectively)					(35,229)
Repurchases of common stock, shares						3,376
Shares tendered in payment of the exercise price of stock options, shares						11
Employee stock purchase plan, shares	(51)					(51)
Repurchases of common stock						(44,375)
Shares tendered in payment of the exercise price of stock options						(161)
Balance at end of period at Dec. 31, 2012		685	400,688	(2,713)	40,203	(269,017)
Shares at end of period at Dec. 31, 2012		68,531				33,980
Issuance for stock-based compensation and dividends, net of forfeitures		882
Exercise of stock options	67	67
Issuance for stock-based compensation and dividends, net of forfeitures		9	72
Exercise of stock options		1	597
Income tax benefit from stock-based compensation			399
Stock-based compensation expense			2,570
Employee stock purchase plan	613		274			339
Pension and post-retirement plans, net of tax of $394, $1,919 and $854, respectively	3,030			3,030
Net income (loss)	10,787				10,787
Dividends, net of forfeitures ($0.41, $0.10 and $1.00 per share, respectively)					(3,378)
Repurchases of common stock, shares						1,812
Shares tendered in payment of the exercise price of stock options, shares						0
Employee stock purchase plan, shares	(41)					(41)
Repurchases of common stock						(27,313)
Shares tendered in payment of the exercise price of stock options						0
Balance at end of period at Dec. 31, 2013	157,233	695	404,600	317	47,612	(295,991)
Shares at end of period at Dec. 31, 2013		69,480				35,751
Issuance for stock-based compensation and dividends, net of forfeitures		444
Exercise of stock options	105	105
Issuance for stock-based compensation and dividends, net of forfeitures		4	369
Exercise of stock options		1	1,213
Income tax benefit from stock-based compensation			595
Stock-based compensation expense			5,475
Employee stock purchase plan	699		390			309
Pension and post-retirement plans, net of tax of $394, $1,919 and $854, respectively	(688)			(688)
Net income (loss)	90,915				90,915
Dividends, net of forfeitures ($0.41, $0.10 and $1.00 per share, respectively)					(13,149)
Repurchases of common stock, shares						4,896
Shares tendered in payment of the exercise price of stock options, shares						4
Employee stock purchase plan, shares	(35)					(35)
Repurchases of common stock						(103,195)
Shares tendered in payment of the exercise price of stock options						(84)
Balance at end of period at Dec. 31, 2014	$ 139,388	$ 700	$ 412,642	$ (371)	$ 125,378	$ (398,961)
Shares at end of period at Dec. 31, 2014		70,029				40,616