Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Narrative) (Details)

v2.4.0.8
Stock-Based Compensation (Narrative) (Details) (USD $)
3 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Restricted Stock Units [Member]
   
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]    
Unrecognized costs related to share based compensation $ 16,117,000  
Weighted average period of recognition of unrecognized costs related to stock options, years 2 years 8 months 10 days  
Restricted stock units granted (in shares) 99,953 128,989
Employee Stock Options [Member]
   
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]    
Stock options granted (in shares) 218,274 298,805
Unrecognized costs related to share based compensation $ 7,912,000  
Weighted average period of recognition of unrecognized costs related to stock options, years 2 years 8 months 25 days