v2.4.0.6
Common Stock and Stock Plans, Stock Option Plans (Details) (USD $)
In Millions, except Share data, unless otherwise specified
 12 Months Ended
Dec. 31, 2011
years
Incentive Compensation Plans [Member]
  
Employee Stock Options [Abstract]  
Options outstanding, weighted-average remaining contractual term (in yrs.) 4.3
Options outstanding, aggregate intrinsic value $ 890
Options outstanding, shares, beginning balance 306,770,791
Options granted, shares 953,308
Options, canceled or forfeited, shares (11,457,278)
Options, Exercised, shares (24,968,218)
Options outstanding, shares, ending balance 271,298,603
Options outstanding, weighted-average exercise price, beginning balance $ 38.11
Options granted, weighted-average exercise price $ 30.62
Options, canceled or forfeited, weighted-average exercise price $ 73.47
Options, Exercised, weighted-average exercise price $ 21.28
Options outstanding, weighted-average exercise price, ending balance $ 38.14
Options exercisable and expected to be exercisable, shares 271,298,603
Options exercisable and expected to be exercisable, weighted-average exercise price $ 38.14
Options exercisable and expected to be exercisable, weighted-average remaining contractual term (in yrs.) 4.3
Options exercisable and expected to be exercisable, aggregate intrinsic value 890
Options exercisable, shares 245,592,111
Options exercisable, weighted-average exercise price $ 40.70
Options exercisable, weighted-average remaining contractual term (in yrs.) 4.1
Options exercisable, aggregate intrinsic value 529
PartnerShares Plan [Member]
  
Employee Stock Options [Abstract]  
Options outstanding, weighted-average remaining contractual term (in yrs.) 0.2
Options outstanding, aggregate intrinsic value 17
Options outstanding, shares, beginning balance 8,474,545
Options, canceled or forfeited, shares (137,253)
Options, Exercised, shares (859,820)
Options outstanding, shares, ending balance 7,477,472
Options outstanding, weighted-average exercise price, beginning balance $ 25.21
Options, canceled or forfeited, weighted-average exercise price $ 24.94
Options, Exercised, weighted-average exercise price $ 24.85
Options outstanding, weighted-average exercise price, ending balance $ 25.25
Options exercisable, shares 7,477,472
Options exercisable, weighted-average exercise price $ 25.25
Options exercisable, weighted-average remaining contractual term (in yrs.) 0.2
Options exercisable, aggregate intrinsic value 17
Director Awards [Member]
  
Employee Stock Options [Abstract]  
Options outstanding, weighted-average remaining contractual term (in yrs.) 3.6
Options outstanding, aggregate intrinsic value 1
Options outstanding, shares, beginning balance 797,864
Options granted, shares 21,940
Options, canceled or forfeited, shares (32,412)
Options, Exercised, shares (65,960)
Options outstanding, shares, ending balance 721,432
Options outstanding, weighted-average exercise price, beginning balance $ 29.10
Options granted, weighted-average exercise price $ 28.68
Options, canceled or forfeited, weighted-average exercise price $ 29.12
Options, Exercised, weighted-average exercise price $ 23.90
Options outstanding, weighted-average exercise price, ending balance $ 29.56
Options exercisable, shares 721,432
Options exercisable, weighted-average exercise price $ 29.56
Options exercisable, weighted-average remaining contractual term (in yrs.) 3.6
Options exercisable, aggregate intrinsic value $ 1