Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2011
Tax Credit Carryforward [Line Items]
Decrease in deferred tax assets reflecting the current tax deduction related to payments made in connection with the covered litigation	$ 1,600,000,000
US income before taxes	5,992,000,000		1,030,000,000		4,650,000,000
U.S. federal statutory rate	35.00%		35.00%		35.00%
Loss Contingency, Loss in Period	3,000,000		4,100,000,000		7,000,000
Income Taxes Receivable	253,000,000
Income taxes receivable included in prepaid and other current assets	142,000,000		179,000,000
Income taxes payable included in accrued taxes as part of accrued liabilities	64,000,000		58,000,000
Accrued income taxes included in other long-term liabilities	453,000,000	[1]	171,000,000	[1]
Cumulative undistributed earnings of the Company's international subsidiaries intended to be reinvested indefinitely outside the U.S	3,800,000,000
Decreased Singapore tax as a result of the tax incentive agreement	(158,000,000)		(130,000,000)		(111,000,000)
Benefit of the tax incentive agreement on diluted net income per share	$ 0.24		$ 0.19		$ 0.16
Total unrecognized tax benefits exclusive of interest and penalties	1,023,000,000		679,000,000		850,000,000
Unrecognized tax benefits, if recognized, would reduce the effective tax rate in a future period	801,000,000		537,000,000
Interest expense included in interest expense and administrative and other	9,000,000		45,000,000		7,000,000
Reversal of penalties upon the effective settlement of uncertainties surrounding the timing of certain deductions	4,000,000		1,000,000		2,000,000
Accrued interest related to uncertain tax positions in other long term liabilities	29,000,000		20,000,000
Accrued penalties related to uncertain tax positions in other long term liabilities	3,000,000		7,000,000
Non United States Customers
Tax Credit Carryforward [Line Items]
US income before taxes	2,000,000,000		1,600,000,000		1,300,000,000
Federal
Tax Credit Carryforward [Line Items]
Research and development tax credit carryforwards	2,000,000
Alternative minimum tax credits	1,000,000
State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards	56,000,000
Research and development tax credit carryforwards	21,000,000
Foreign Country
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards	$ 115,000,000

[1] The increase in accrued income taxes is primarily related to increases in unrecognized tax benefits.