CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $) In Thousands, except Share data	Total	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income/(Loss) [Member]	Common Stock in Treasury [Member]
Beginning Balance at Dec. 31, 2011	$ 168,799	$ 371	$ 189,573	$ 827,675	$ (9,479)	$ (839,341)
Beginning Balance (in shares) at Dec. 31, 2011		37,069,000				(10,969,000)
Net income	149,933			149,933
Other comprehensive income	509				509
Equity award vesting and exercises (in shares)						272,000
Equity award vesting and exercises	8,345			(9,062)		17,407
Tax benefit from equity awards	922		922
Stock-based compensation	12,600		12,600
Common shares repurchased (in shares)	(3,025,700)					(3,026,000)
Common shares repurchased	(207,918)					(207,918)
Issuance of shares for Directors' compensation (in shares)						1,000
Issuance of shares for Directors' compensation	37			(1)		38
Shares tendered for taxes (in shares)						(22,000)
Shares tendered for taxes	(1,452)					(1,452)
Ending Balance at Sep. 30, 2012	131,775	371	203,095	968,545	(8,970)	(1,031,266)
Ending Balance (in shares) at Sep. 30, 2012		37,069,000				(13,744,000)
Net income	(9,468)			(9,468)
Other comprehensive income	1,040				1,040
Equity award vesting and exercises (in shares)
Equity award vesting and exercises	0			(5)		5
Tax benefit from equity awards	(4)		(4)
Stock-based compensation	3,612		3,612
Shares tendered for taxes (in shares)
Shares tendered for taxes	(1)					(1)
Ending Balance at Dec. 31, 2012	126,954	371	206,703	959,072	(7,930)	(1,031,262)
Ending Balance (in shares) at Dec. 31, 2012		37,069,000				(13,744,000)
Net income	70,930			70,930
Other comprehensive income	215				215
Equity award vesting and exercises (in shares)						68,000
Equity award vesting and exercises	0		(3,277)			3,277
Tax benefit from equity awards	(5,410)		(5,410)
Stock-based compensation	8,698		8,698
Common shares repurchased (in shares)	0
Common shares repurchased	0
Shares tendered for taxes (in shares)						(23,000)
Shares tendered for taxes	(390)					(390)
Ending Balance at Sep. 30, 2013	$ 200,997	$ 371	$ 206,714	$ 1,030,002	$ (7,715)	$ (1,028,375)
Ending Balance (in shares) at Sep. 30, 2013		37,069,000				(13,699,000)