v3.3.0.814
Summary of Option Activity (Detail)
$ / shares in Units, $ in Millions
 12 Months Ended
Sep. 30, 2015
USD ($)
$ / shares
shares
Options  
Beginning balance | shares 11,649,704
Granted | shares 1,444,376
Forfeited | shares (379,662)
Exercised | shares (3,036,701)
Ending balance | shares 9,677,717
Options exercisable at September 30, 2015 | shares 7,083,305
Options exercisable and expected to be vested at September 30, 2015 | shares 9,392,332 [1]
Weighted average price per share  
Beginning balance $ 22.52
Granted 62.87
Forfeited 50.53
Exercised 20.53
Ending balance 28.07
Options exercisable at September 30, 2015 18.26
Options exercisable and expected to vest at September 30, 2015(2) $ 27.26 [1]
Weighted-Average Remaining Contractual Term  
Outstanding at September 30, 2015 5 years
Options exercisable at September 30, 2015 3 years 8 months 12 days
Options exercisable and expected to vest at September 30, 2015(2) 4 years 10 months 24 days [1]
Aggregate Intrinsic Value  
Outstanding at September 30, 2015 | $ $ 402
Options exercisable at September 30, 2015 | $ 364
Options exercisable and expected to vest at September 30, 2015(2) | $ $ 398 [1]
Stock price used to calculate aggregate intrinsic value $ 69.66
[1] Applies a forfeiture rate to unvested options outstanding at September 30, 2015 to estimate the options expected to vest in the future.