Quarterly report pursuant to Section 13 or 15(d)

Activity in Deferred Compensation Program (Detail)

v2.4.0.8
Activity in Deferred Compensation Program (Detail) (USD $)
In Millions, unless otherwise specified
6 Months Ended
Jun. 30, 2013
Dec. 31, 2012
Jun. 30, 2013
Treasury Stock [Member]
Jun. 30, 2012
Treasury Stock [Member]
Jun. 30, 2013
Deferred Compensation Obligations
Jun. 30, 2012
Deferred Compensation Obligations
Stockholders Equity Note [Roll Forward]            
Balance at beginning of period (1) (1) (1) (2)    
Reinvested dividends     0 0    
Benefit payments     0 0    
Balance at end of period (1) (1) (1) (2)    
Balance at beginning of period $ 3,617 $ 4,653 $ (78) $ (88) $ 78 $ 88
Reinvested dividends     (2) (2) 2 2
Benefit payments     13 14 (13) (14)
Balance at end of period $ 3,617 $ 4,653 $ (67) $ (76) $ 67 $ 76