Long-Term Debt (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Debt Instrument [Line Items]
Long-term debt	$ 4,322	$ 4,347
Less: Current maturities	267	560
Total, net	4,055	3,787
Long-term debt maturing during year two	520
Long-term debt maturing during year three	289
Long-term debt maturing during year four	250
Long-term debt maturing during year five	250
Interest paid related to short-term borrowings and long-term debt	226	234	239
4.625% Notes Due October 2012 [Member]
Debt Instrument [Line Items]
Long-term debt	0	250
Notes interest rate, percentage	4.625%	4.625%
Debt Instruments Maturity Date	October 2012	October 2012
4.5% Notes Due May 2013 [Member]
Debt Instrument [Line Items]
Long-term debt	0	250
Notes interest rate, percentage	4.50%	4.50%
Debt Instruments Maturity Date	May 2013	May 2013
5.625% Notes Due November 2013 [Member]
Debt Instrument [Line Items]
Long-term debt	250	250
Notes interest rate, percentage	5.625%	5.625%
Debt Instruments Maturity Date	November 2013	November 2013
5.0% Notes Due December 2014 [Member]
Debt Instrument [Line Items]
Long-term debt	250	250
Notes interest rate, percentage	5.00%	5.00%
Debt Instruments Maturity Date	December 2014	December 2014
4.125% Notes Due April 2015 [Member]
Debt Instrument [Line Items]
Long-term debt	250	250
Notes interest rate, percentage	4.125%	4.125%
Debt Instruments Maturity Date	April 2015	April 2015
4.75% Notes Due October 2015 [Member]
Debt Instrument [Line Items]
Long-term debt	250	250
Notes interest rate, percentage	4.75%	4.75%
Debt Instruments Maturity Date	October 2015	October 2015
5.125% Notes Due December 2016 [Member]
Debt Instrument [Line Items]
Long-term debt	250	250
Notes interest rate, percentage	5.125%	5.125%
Debt Instruments Maturity Date	December 2016	December 2016
5.375% Notes Due October 2017 [Member]
Debt Instrument [Line Items]
Long-term debt	250	250
Notes interest rate, percentage	5.375%	5.375%
Debt Instruments Maturity Date	October 2017	October 2017
5.25% Notes Due October 2018[Member]
Debt Instrument [Line Items]
Long-term debt	400	400
Notes interest rate, percentage	5.25%	5.25%
Debt Instruments Maturity Date	October 2018	October 2018
5.0% Notes Due April 2019 [Member]
Debt Instrument [Line Items]
Long-term debt	250	250
Notes interest rate, percentage	5.00%	5.00%
Debt Instruments Maturity Date	April 2019	April 2019
4.875% Notes Due October 2019 [Member]
Debt Instrument [Line Items]
Long-term debt	500	500
Notes interest rate, percentage	4.875%	4.875%
Debt Instruments Maturity Date	October 2019	October 2019
4.25% Notes Due November 2020 [Member]
Debt Instrument [Line Items]
Long-term debt	300	300
Notes interest rate, percentage	4.25%	4.25%
Debt Instruments Maturity Date	November 2020	November 2020
2.625% Notes Due February 2023 [Member]
Debt Instrument [Line Items]
Long-term debt	500	0
Notes interest rate, percentage	2.625%	2.625%
Debt Instruments Maturity Date	February 2023	February 2023
6.0% Notes Due August 2032 [Member]
Debt Instrument [Line Items]
Long-term debt	250	250
Notes interest rate, percentage	6.00%	6.00%
Debt Instruments Maturity Date	August 2032	August 2032
6.125% Notes Due April 2039 [Member]
Debt Instrument [Line Items]
Long-term debt	250	250
Notes interest rate, percentage	6.125%	6.125%
Debt Instruments Maturity Date	April 2039	April 2039
5.25% Notes Due November 2039 [Member]
Debt Instrument [Line Items]
Long-term debt	300	300
Notes interest rate, percentage	5.25%	5.25%
Debt Instruments Maturity Date	November 2039	November 2039
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Long-term debt	$ 72	$ 97

Debt instruments maturity date.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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The amount of cash paid for interest during the period.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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