Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation - Summary of Restricted Stock Transactions (Details)

v3.8.0.1
Share-Based Compensation - Summary of Restricted Stock Transactions (Details) - $ / shares
shares in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Shares    
Unvested at January 1, 2017 8,848  
Granted (in shares) 12,422  
Vested (in shares) (398)  
Forfeited (in shares) (384)  
Unvested at December 31, 2017 20,488  
Weighted-Average Grant Date Fair Value    
Unvested (in dollars per share)   $ 3.52
Granted (in dollars per share) $ 9.59  
Vested (in dollars per share) 9.28  
Forfeited (in dollars per share) $ 11.14