XML 54 R100.htm IDEA: XBRL DOCUMENT v2.4.0.6
Severance Costs - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Income Statement [Abstract]      
Severance and early retirement program costs $ 35 $ 15 $ 14