Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Narrative) (Details)

v3.4.0.3
Stock-Based Compensation (Narrative) (Details) - USD ($)
3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
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 $ 19,495,000  
Weighted average period of recognition of unrecognized costs related to stock options, years 2 years 7 months  
Restricted stock units granted (in shares) 175,938 180,789
Employee Stock Options [Member]    
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]    
Stock options granted (in shares) 389,186 462,391
Unrecognized costs related to share based compensation $ 9,478,000  
Weighted average period of recognition of unrecognized costs related to stock options, years 2 years 9 months