Net Income Per Share - Anti-dilutive Securities (Details)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Warrants to purchase common stock    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Anti-dilutive securities excluded from computation of diluted earnings per share 0 42,243
Stock option awards    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Anti-dilutive securities excluded from computation of diluted earnings per share 17 0