XML 53 R58.htm IDEA: XBRL DOCUMENT v2.4.0.8
Net Income Per Common Share - Average Exercise Prices of Options Excluded from Computation of Diluted Net Income Per Common Share (Detail) (USD $)
3 Months Ended 9 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Sep. 30, 2013
Sep. 30, 2012
Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Abstract]        
Shares 3,804 479,000 330,165 597,200
Average Exercise Price $ 50.74 $ 39.21 $ 40.09 $ 38.66