XML 68 R56.htm IDEA: XBRL DOCUMENT v3.6.0.2
Stock-Based Compensation (Detail) - Stock-Based Compensation Expense By Award Type - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense $ 46.7 $ 46.1 $ 38.8
Stock appreciation rights      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 5.6 5.7 5.0
Common stock equivalents      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense 0.7 0.6 0.6
Restricted stock units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense $ 40.4 $ 39.8 $ 33.2