Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Stock Option Activity (Details)

v3.8.0.1
Stock-based Compensation - Stock Option Activity (Details) - Stock Options [Member]
$ / shares in Units, $ in Thousands
 3 Months Ended
Mar. 31, 2018
USD ($)
$ / shares
shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Number of shares, Outstanding at January 1, 2018 | shares 1,622,065
Number of shares, Granted | shares 133,000
Number of shares, Exercised | shares (400)
Number of shares, Forfeited, expired or cancelled | shares (101,469)
Number of shares, Outstanding at March 31, 2018 | shares 1,653,196
Number of shares, Exercisable at March 31, 2018 | shares 915,442
Weighted Average Exercise Price Per Share, Outstanding at January 1, 2018 | $ / shares $ 24.54
Weighted Average Exercise Price Per Share, Granted | $ / shares 26.90
Weighted Average Exercise Price Per Share, Exercised | $ / shares 33.80
Weighted Average Exercise Price Per Share, Forfeited, expired or cancelled | $ / shares 54.24
Weighted Average Exercise Price Per Share, Outstanding at March 31, 2018 | $ / shares 22.91
Weighted Average Exercise Price Per Share, Exercisable at March 31, 2018 | $ / shares $ 29.09
Weighted Average Contractual Term (in years), Outstanding at March 31, 2018 8 years 3 months 25 days
Weighted Average Contractual Term (in years), Exercisable at March 31, 2018 7 years 6 months 18 days
Aggregate Intrinsic Value, Outstanding at March 31, 2018 | $ $ 16,625
Aggregate Intrinsic Value, Exercisable at March 31, 2018 | $ $ 9,959