XML 66 R68.htm IDEA: XBRL DOCUMENT v2.4.0.8
Summary of Stock Options Issued Pursuant to Stock Incentive Plans (Detail) (USD $)
 12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Number of Shares      
Outstanding, Beginning Balance 2,968,582 3,490,056 3,510,538
Granted 402,673 435,367 367,202
Exercised (826,061) (847,301) (361,093)
Forfeited (75,158) (105,540) (26,591)
Expired (429) (4,000)  
Outstanding, Ending Balance 2,469,607 2,968,582 3,490,056
Number of Shares Exercisable, Ending Balance 1,780,136    
Weighted-Average Exercise Price      
Beginning Balance $ 27.15 $ 23.28 $ 21.55
Granted $ 57.90 $ 42.43 $ 28.95
Exercised $ 23.42 $ 19.74 $ 12.40
Forfeited $ 38.37 $ 22.19 $ 20.53
Expired $ 28.94 $ 10.19  
Ending Balance $ 33.07 $ 27.15 $ 23.28
Weighted Average Exercise Price Exercisable, Ending Balance $ 26.48    
Weighted-Average Remaining Contractual Term (Years)      
Weighted Average Remaining Contractual Term (Years), Outstanding as of end of period 5 years 8 months 27 days    
Weighted Average Remaining Contractual Term (Years), Exercisable as of end of period 4 years 4 months 10 days    
Aggregate Intrinsic Value of In-the-Money Options      
Aggregate Intrinsic Value of In-the-Money Options, Outstanding as of end of year $ 78,851,289    
Aggregate Intrinsic Value of In-the-Money Options, Exercisable as of end of year $ 68,575,316