CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY AND COMPREHENSIVE INCOME (LOSS) (Unaudited) (USD $) In Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Balance, beginning at Dec. 31, 2009	$ 107,607	$ 42	$ 439,943	$ (329,330)	$ (307)	$ (2,741)
Balance, beginning (in shares) at Dec. 31, 2009		32,142				(200)
Comprehensive income (loss):
Net income (loss)	(50,925)			(50,925)
Net change in unrealized loss on securities	15				15
Total comprehensive income (loss)	(50,910)
Compensation expenses for share-based payment arrangements	7,726		7,726
Issuance of restricted stock, net of forfeitures (in shares)		187
Sale of common stock under employee stock purchase plans and exercise of stock options (in shares)		776
Sale of common stock under employee stock purchase plans and exercise of stock options	2,987	1	2,986
Balance, ending at Sep. 30, 2010	67,410	43	450,655	(380,255)	(292)	(2,741)
Balance, ending (in shares) at Sep. 30, 2010		33,105				(200)
Balance, beginning at Dec. 31, 2010	51,308	43	453,353	(399,055)	(292)	(2,741)
Balance, beginning (in shares) at Dec. 31, 2010		33,326				(200)
Comprehensive income (loss):
Net income (loss)	21,127			21,127
Net change in unrealized loss on securities	16				16
Total comprehensive income (loss)	21,143
Compensation expenses for share-based payment arrangements	4,695		4,695
Issuance of restricted stock, net of forfeitures (in shares)		(34)
Sale of common stock under employee stock purchase plans and exercise of stock options (in shares)		665
Sale of common stock under employee stock purchase plans and exercise of stock options	3,234	1	3,233
Balance, ending at Sep. 30, 2011	$ 80,380	$ 44	$ 461,281	$ (377,928)	$ (276)	$ (2,741)
Balance, ending (in shares) at Sep. 30, 2011		33,957				(200)