Debt - Additional Information (Detail) - USD ($) |
12 Months Ended | |
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Sep. 30, 2015 |
Sep. 30, 2014 |
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| Revolving Credit Facility | ||
| Debt Instrument [Line Items] | ||
| Credit Facility Maximum Borrowing Capacity | $ 3,000,000,000 | $ 3,000,000,000 |
| Credit Facility Commitment Fee Percentage | 0.07% | |
| Credit Facility Amount Outanding | $ 0 | |
| Revolving Credit Facility | Minimum | ||
| Debt Instrument [Line Items] | ||
| Credit Facility Interest Rate During Period | 0.00% | |
| Revolving Credit Facility | Maximum | ||
| Debt Instrument [Line Items] | ||
| Credit Facility Interest Rate During Period | 0.75% | |
| Commercial Paper | ||
| Debt Instrument [Line Items] | ||
| Commercial Paper Program, Amount Available | $ 3,000,000,000 | |
| Commercial Paper Program, Maturity Period | P397D | |
| Commercial Paper Program, Amount Outstanding | $ 0 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used. No definition available.
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- Definition The effective interest rate at the end of the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Commercial Paper, Amount Outstanding No definition available.
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- Definition Commercial Paper, Maximum Borrowing Capacity No definition available.
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