Quarterly report pursuant to Section 13 or 15(d)

Activity in Deferred Compensation Program (Detail)

v2.4.0.6
Activity in Deferred Compensation Program (Detail) (USD $)
In Millions, unless otherwise specified
6 Months Ended
Jun. 30, 2012
Dec. 31, 2011
Jun. 30, 2012
Treasury Stock [Member]
Jun. 30, 2011
Treasury Stock [Member]
Jun. 30, 2012
Deferred Compensation Obligations
Jun. 30, 2011
Deferred Compensation Obligations
Stockholders Equity Note [Roll Forward]            
Balance at beginning of period (2) (2) (2) (2)    
Reinvested dividends     0 0    
Benefit payments     0 0    
Balance at end of period (2) (2) (2) (2)    
Balance at beginning of period $ 7,645 $ 7,035 $ (88) $ (103) $ 88 $ 103
Reinvested dividends     (2) (2) 2 2
Benefit payments     14 19 (14) (19)
Balance at end of period $ 7,645 $ 7,035 $ (76) $ (86) $ 76 $ 86