Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Selling, general and administrative expenses (Details)

v3.8.0.1
Selling, general and administrative expenses (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Selling, General and Administrative Expense [Abstract]      
Personnel expenses $ 156,726 $ 149,505 $ 161,967
Share-based compensation 107,719 102,843 100,162
Travel expenses 19,774 21,201 23,090
Professional services 28,585 30,983 42,921
Office expenses 16,105 20,703 26,989
Directors’ expenses 3,345 3,051 2,780
Other expenses 16,037 22,726 23,399
Total selling, general and administrative expenses $ 348,291 $ 351,012 $ 381,308