Annual report pursuant to Section 13 and 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
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense $ 128,431 $ 138,458 $ 111,645
RSUs      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 4 years    
Stock-based compensation expense $ 114,400 $ 124,300 $ 96,100
Compensation cost not yet recognized $ 175,200    
Service period over which company recognizes stock-based compensation (years) 2 years 10 days