Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Summary of Restricted Stock Award and Unit Activity) (Details)

v3.7.0.1
Stock-Based Compensation (Summary of Restricted Stock Award and Unit Activity) (Details) - Restricted Stock
6 Months Ended
Jun. 30, 2017
$ / shares
shares
Number of Unvested Restricted Shares  
Unvested shares as of January 1, 2017 | shares 613,056
Granted (in shares) | shares 525,808
Vested (in shares) | shares (172,988)
Forfeited (in shares) | shares (66,661)
Unvested shares as of June 30, 2017 | shares 899,215
Weighted Average Grant Date Fair Value  
Unvested shares as of January 1, 2017 | $ / shares $ 32.90
Granted (in dollars per share) | $ / shares 17.31
Vested (in dollars per share) | $ / shares 32.06
Forfeited (in dollars per share) | $ / shares 31.18
Unvested shares as of June 30, 2017 | $ / shares $ 24.08