Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation Plans and Awards - RSUs Narrative (Details)

v3.8.0.1
Stock-based Compensation Plans and Awards - RSUs Narrative (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation expense $ 26,436 $ 29,618
RSUs    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation expense $ 24,700 $ 25,400
RSUs | Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 3 years  
RSUs | Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 4 years