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
3 Months Ended
Mar. 31, 2017
$ / shares
shares
Number of Unvested Restricted Shares  
Unvested shares as of January 1, 2016 (in shares) | shares 613,056
Granted (in shares) | shares 477,768
Vested (in shares) | shares (153,868)
Forfeited (in shares) | shares (65,438)
Unvested shares as of March 31, 2017 (in shares) | shares 871,518
Weighted Average Grant Date Fair Value  
Unvested shares as of January 1, 2016 (in dollars per share) | $ / shares $ 32.90
Granted (in dollars per share) | $ / shares 17.74
Vested (in dollars per share) | $ / shares 31.98
Forfeited (in dollars per share) | $ / shares 31.23
Unvested shares as of March 31, 2017 (in dollars per share) | $ / shares $ 24.88