Annual report pursuant to Section 13 and 15(d)

Earnings Per Share - Additional Information (Detail)

v2.4.0.8
Earnings Per Share - Additional Information (Detail)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Earnings Per Share [Abstract]    
Number of common shares covered by out-of-the-money stock options 0.2 0.1