Annual report pursuant to Section 13 and 15(d)

Stock-Based Awards (Stock-Based Compensation Expense) (Details)

v3.6.0.2
Stock-Based Awards (Stock-Based Compensation Expense) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]      
Stock-based compensation expense $ 19,233 $ 18,408 $ 15,606
Income tax benefit (6,734) (6,563) (5,685)
Stock-based compensation expense after income taxes 12,499 11,845 9,921
Selling And Marketing [Member]      
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]      
Stock-based compensation expense 6,412 6,171 4,736
General And Administrative [Member]      
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]      
Stock-based compensation expense $ 12,821 $ 12,237 $ 10,870