XML 52 R40.htm IDEA: XBRL DOCUMENT v3.3.1.900
Stock Based Compensation - Additional Information (Detail)
$ / shares in Units, $ in Millions
3 Months Ended 6 Months Ended
Nov. 30, 2015
USD ($)
$ / shares
shares
Nov. 30, 2014
USD ($)
Nov. 30, 2015
USD ($)
$ / shares
shares
Nov. 30, 2014
USD ($)
$ / shares
Class A Convertible Common Stock        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Common stock, no par value | $ / shares $ 0   $ 0  
Common stock, shares authorized | shares 400,000,000   400,000,000  
Common stock, conversion basis     Each share of Class A Common Stock is convertible into one share of Class B Common Stock.  
Common stock, Class A conversion ratio to Class B (in shares)     1  
Class B Common Stock        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Common stock, no par value | $ / shares $ 0   $ 0  
Common stock, shares authorized | shares 2,400,000,000   2,400,000,000  
Stock Incentive Plan | Class B Common Stock        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Shares available for grant (in shares) | shares 718,000,000   718,000,000  
Stock Incentive Plan | Employee Stock Option | Class B Common Stock        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock options vesting period (in years)     4 years  
Stock options expiration from the date of grant (in years)     10 years  
Accelerated stock option expense | $ $ 8 $ 5 $ 14 $ 9
Unrecognized compensation costs from stock options, net of estimated forfeitures | $ $ 333   $ 333  
Unrecognized compensation costs from stock options, net of estimated forfeitures, to be recognized as operating overhead expense over a weighted average period (in years)     2 years 6 months  
Weighted average fair value per share of the options granted (in dollars per share) | $ / shares     $ 12.67 $ 8.47
Minimum term of market traded options for estimates of expected volatility (in years)     1 year  
Employee Stock Purchase Plans | Employee Stock | Class B Common Stock        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Employee stock purchase plans, payroll deductions (percent) 10.00%   10.00%  
Employee stock purchase plan offering period (in months)     6 months  
Shares purchased, price as percentage of lower of the fair market value (percent) 85.00%   85.00%