v2.3.0.11
Stock-Based Compensation (Details 4) (Stock Option [Member], USD $)
In Millions
3 Months Ended 6 Months Ended
Jun. 30, 2011
Jun. 30, 2010
Jun. 30, 2011
Jun. 30, 2010
Stock Option [Member]
       
Stock Option Aggregate Disclosures [Abstract]        
Intrinsic value of stock options exercised $ 76 $ 8 $ 165 $ 26
Cash received from option exercises 44 11 106 34
Treasury shares repurchased for employee payroll taxes (16) (2) (41) (8)
Tax benefit realized from option exercises 29 3 63 10
Aggregate grant-date fair value of stock options vested $ 1 $ 0 $ 19 $ 19