CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Total
Balance, beginning at Dec. 31, 2010	$ 43	$ 453,353	$ (399,055)	$ (292)	$ (2,741)	$ 51,308
Balance, beginning (in shares) at Dec. 31, 2010	33,326				(200)
Net (loss) income	0	0	10,381	0	0	10,381
Other comprehensive income	0	0	0	24	0	24
Compensation expenses for share-based payment arrangements	0	6,362	0	0	0	6,362
Forfeitures of restricted stock	0	0	0	0	0	0
Forfeitures of restricted stock (in shares)	(38)				0
Sale of common stock under employee stock purchase plans and exercise of stock options	1	3,725	0	0	0	3,726
Sale of common stock under employee stock purchase plans and exercise of stock options (in shares)	758				0
Balance, ending at Dec. 31, 2011	44	463,440	(388,674)	(268)	(2,741)	71,801
Balance, ending (in shares) at Dec. 31, 2011	34,046				(200)
Net (loss) income	0	0	(35,431)	0	0	(35,431)
Other comprehensive income	0	0	0	8	0	8
Compensation expenses for share-based payment arrangements	0	6,536	0	0	0	6,536
Forfeitures of restricted stock	0	0	0	0	0	0
Forfeitures of restricted stock (in shares)	(6)				0
Sale of common stock in public offering, net of underwriting discounts and commissions and offering expenses	17	23,331	0	0	0	23,348
Sale of common stock in public offering, net of underwriting discounts and commissions and offering expenses (in shares)	12,650				0
Sale of common stock under employee stock purchase plans and exercise of stock options	0	306	0	0	0	306
Sale of common stock under employee stock purchase plans and exercise of stock options (in shares)	75				0
Balance, ending at Dec. 31, 2012	61	493,613	(424,105)	(260)	(2,741)	66,568
Balance, ending (in shares) at Dec. 31, 2012	46,765				(200)
Net (loss) income	0	0	(42,572)	0	0	(42,572)
Other comprehensive income	0	0	0	68	0	68
Compensation expenses for share-based payment arrangements	0	3,546	0	0	0	3,546
Forfeitures of restricted stock	0	0	0	0	0	0
Forfeitures of restricted stock (in shares)	(1)				0
Acquisition of subsidiary, net of issuance costs	6	11,214	0	0	0	11,220
Stock Issued During Period, Shares, Acquisitions	4,472				0
Sale of common stock in public offering, net of underwriting discounts and commissions and offering expenses	12	40,066	0	0	0	40,078
Sale of common stock in public offering, net of underwriting discounts and commissions and offering expenses (in shares)	9,775				0
Sale of common stock under stock incentive plan and exercise of stock options	0	71	0	0	0	71
Sale of common stock under stock incentive plan and exercise of stock options (in shares)	14				0
Balance, ending at Dec. 31, 2013	$ 79	$ 548,510	$ (466,677)	$ (192)	$ (2,741)	$ 78,979
Balance, ending (in shares) at Dec. 31, 2013	61,025				(200)