Awards Granted to Company Employees and Non-employee Directors Under the 2007 Equity Incentive Compensation Plan (Detail) (USD $)	6 Months Ended
	Mar. 31, 2013
Non-qualified stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	553,034
Weighted-Average Grant Date Fair Value	$ 38.79
Weighted-Average Exercise Price	$ 145.81
Restricted stock awards (RSAs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	863,383
Weighted-Average Grant Date Fair Value	$ 145.89
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	325,232
Weighted-Average Grant Date Fair Value	$ 145.67
Performance-based shares(1)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	230,518	[1]
Weighted-Average Grant Date Fair Value	$ 164.14	[1]

[1] Represents the maximum number of performance-based shares which could be earned.