Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Narrative) (Details)

v3.7.0.1
Stock-Based Compensation (Narrative) (Details) - USD ($)
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Employee Stock Options [Member]    
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]    
Stock options granted (in shares) 455,342 389,186
Unrecognized costs related to share based compensation $ 10,424,000  
Weighted average period of recognition of unrecognized costs related to stock options, years 2 years 10 months 15 days  
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 $ 20,609,000  
Weighted average period of recognition of unrecognized costs related to stock options, years 2 years 8 months 28 days  
Restricted stock units granted (in shares) 233,175 175,938