Annual report pursuant to Section 13 and 15(d)

Roll-forward of Common Stock, Additional Paid-in Capital, and Retained Earnings Accounts (Detail)

v2.4.0.6
Roll-forward of Common Stock, Additional Paid-in Capital, and Retained Earnings Accounts (Detail) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 12 Months Ended
Dec. 31, 2011
Sep. 30, 2011
Jun. 30, 2011
Mar. 31, 2011
Dec. 31, 2010
Sep. 30, 2010
Jun. 30, 2010
Mar. 31, 2010
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Stockholders Equity Note [Line Items]                      
Common stock purchases                 (38.7) (12.4) (10.9)
Balance at beginning of period       $ 7,979         $ 7,979    
Net income attributable to controlling interests 725 1,072 1,092 915 1,025 972 826 515 3,804 3,338 1,968
Common stock purchases                 (2,669) (809) (569)
Balance at end of period 7,035       7,979       7,035 7,979  
Class A common stock
                      
Stockholders Equity Note [Line Items]                      
Balance at beginning of year       258       285 258 285 314
Common stock purchases                 (7.0) (6.0) (10.0)
Stock award plans                 7 6 5
Common stock issuances                 3 3 4
Conversions of class A to class B common stock                 (21) (30) (28)
Balance at end of period 240       258       240 258 285
Balance at beginning of period       3       3 3 3 3
Stock award plans                         
Conversions of class A to class B common stock                         
Balance at end of period 3       3       3 3 3
Class B common stock
                      
Stockholders Equity Note [Line Items]                      
Balance at beginning of year       735       711 735 711 684
Common stock purchases                 (31.0) (6.0) (1.0)
Conversions of class A to class B common stock                 21 30 28
Balance at end of period 725       735       725 735 711
Balance at beginning of period       7       7 7 7 7
Conversions of class A to class B common stock                         
Balance at end of period 7       7       7 7 7
Additional Paid-In Capital
                      
Stockholders Equity Note [Line Items]                      
Balance at beginning of period               2   2  
Stock award plans                 388 398 381
Common stock purchases                 (475) (649) (569)
Common stock issuances                 287 249 190
Option Premiums Paid                 (200)    
Balance at end of period                     2
Retained Earnings
                      
Stockholders Equity Note [Line Items]                      
Balance at beginning of period       10,604       9,335 10,604 9,335 9,186
Net income attributable to controlling interests                 3,804 3,338 1,968
Dividends ($2.08, $1.88 and $1.80 per share)                 (2,086) (1,909) (1,819)
Common stock purchases                 (2,194) (160)  
Balance at end of period $ 10,128       $ 10,604       $ 10,128 $ 10,604 $ 9,335