Quarterly report pursuant to Section 13 or 15(d)

Summary of Treasury Stock Activity (Parenthetical) (Detail)

v2.4.0.8
Summary of Treasury Stock Activity (Parenthetical) (Detail) (USD $)
9 Months Ended
Sep. 30, 2014
Minimum
 
Schedule of Treasury Stock [Line Items]  
Market Value of Restricted Shares Withheld $ 27.19
Maximum
 
Schedule of Treasury Stock [Line Items]  
Market Value of Restricted Shares Withheld $ 30.23