v2.4.0.6
Total Stock-Based Compensation Expense (Detail) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
May 31, 2012
May 31, 2011
May 31, 2010
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]      
Stock-based compensation expense $ 130 $ 105 $ 159
Stock Options
      
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]      
Stock-based compensation expense 96 [1] 77 [1] 135 [1]
ESPPs
      
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]      
Stock-based compensation expense 16 14 14
Restricted Stock
      
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]      
Stock-based compensation expense $ 18 $ 14 $ 10
[1] Expense for stock options includes the expense associated with stock appreciation rights. Accelerated stock option expense is recorded for employees eligible for accelerated stock option vesting upon retirement. In the first quarter of fiscal 2011, the Company changed the accelerated vesting provisions of its stock option plan. Under the new provisions, accelerated stock option expense for years ended May 31, 2012 and 2011 was $17 million and $12 million, respectively. The accelerated stock option expense for the year ended May 31, 2010 was $74 million.