v2.4.0.6
Earnings Per Share - Additional Information (Detail)
3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Options not considered in diluted earnings per share computation as they were not dilutive 187,720 416,604 264,389 354,616