CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $)
In Thousands, unless otherwise specified
Total
Common Stock
Treasury Stock
Additional Capital
Accumulated Other Comprehensive Loss
Accumulated Deficit
Balance at Dec. 31, 2009 $ 347,166 $ 24 $ (853) $ 494,783 $ (1,423) $ (145,365)
Balance (in shares) at Dec. 31, 2009     (56)      
Balance (in shares) at Dec. 31, 2009   24,045        
Increase (Decrease) in Stockholders' Equity            
Common stock issued in equity offering, net of costs 107,917 4   107,913    
Common stock issued in equity offering, net of costs (in shares)   3,651        
Common stock issued on exercise of stock options and warrants 7,818 1   7,817    
Common stock issued on exercise of stock options and warrants (in shares)   753        
Common stock issued in purchase (in shares)   41        
Common stock issued under employee stock purchase plan 128     128    
Common stock issued under employee stock purchase plan (in shares)   5        
Common stock issued on vesting of restricted stock and restricted stock units (in shares)   10        
Common stock issued pursuant to restricted stock/restricted stock unit agreement, net of shares tendered to satisfy required tax withholding (1,620)     (1,620)    
Common stock issued pursuant to restricted stock/restricted stock unit agreement, net of shares tendered to satisfy required tax withholding (in shares)   74        
Tax benefit from exercise of non-qualified stock options and vesting of restricted stock 879     879    
Purchase of treasury stock (13,148)   (13,148)      
Purchase of treasury stock (in shares)     (601)      
Share-based compensation 4,805     4,805    
Other comprehensive income (loss) 1,398       1,398  
Net income (loss) 41,569         41,569
Balance at Dec. 31, 2010 496,912 29 (14,001) 614,705 (25) (103,796)
Balance (in shares) at Dec. 31, 2010     (657)      
Balance (in shares) at Dec. 31, 2010   28,579        
Increase (Decrease) in Stockholders' Equity            
Common stock issued on exercise of stock options and warrants 212     212    
Common stock issued on exercise of stock options and warrants (in shares)   16        
Common stock issued under employee stock purchase plan 180     180    
Common stock issued under employee stock purchase plan (in shares)   6        
Common stock issued on vesting of restricted stock and restricted stock units (in shares)   32        
Common stock issued pursuant to restricted stock/restricted stock unit agreement, net of shares tendered to satisfy required tax withholding (1,129)     (1,129)    
Common stock issued pursuant to restricted stock/restricted stock unit agreement, net of shares tendered to satisfy required tax withholding (in shares)   74        
Purchase of treasury stock (21,547)   (21,547)      
Purchase of treasury stock (in shares)     (847)      
Share-based compensation 12,430     12,430    
Other comprehensive income (loss) (3,756)       (3,756)  
Net income (loss) 24,484         24,484
Balance at Dec. 31, 2011 507,786 29 (35,548) 626,398 (3,781) (79,312)
Balance (in shares) at Dec. 31, 2011     (1,504)      
Balance (in shares) at Dec. 31, 2011 28,707 28,707        
Increase (Decrease) in Stockholders' Equity            
Common stock issued on exercise of stock options and warrants 269     269    
Common stock issued on exercise of stock options and warrants (in shares)   38        
Common stock issued in purchase 3,314     3,314    
Common stock issued in purchase (in shares)   357        
Common stock issued under employee stock purchase plan 157     157    
Common stock issued under employee stock purchase plan (in shares)   14        
Common stock issued on vesting of restricted stock and restricted stock units (in shares)   22        
Common stock issued pursuant to restricted stock/restricted stock unit agreement, net of shares tendered to satisfy required tax withholding (93)     (93)    
Common stock issued pursuant to restricted stock/restricted stock unit agreement, net of shares tendered to satisfy required tax withholding (in shares)   25        
Share-based compensation 17,470     17,470    
Other comprehensive income (loss) 2,126       2,126  
Net income (loss) (239,835)         (239,835)
Balance at Dec. 31, 2012 $ 291,194 $ 29 $ (35,548) $ 647,515 $ (1,655) $ (319,147)
Balance (in shares) at Dec. 31, 2012     (1,504)      
Balance (in shares) at Dec. 31, 2012 29,163 29,163