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Stock-Based Compensation - Additional Information (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock based compensation expense $ 5,251 $ 3,391 $ 9,460 $ 6,150
Unamortized compensation expense related to outstanding restricted stock, restricted stock units, and performance units $ 32,000   32,000  
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition 3 years      
Time-Based Restricted Stock        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock based compensation expense $ 1,491 872 2,608 1,852
Restricted Stock Units (RSUs) [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock based compensation expense 2,087 1,531 3,878 2,625
Performance-Based Restricted Stock Units        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock based compensation expense $ 1,673 $ 988 $ 2,974 $ 1,673