Risk Management Activities and Derivative Transactions Offsetting for Derivative Liabilities (Details) $ in Millions |
Jun. 30, 2025
USD ($)
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Sep. 30, 2024
USD ($)
Bond_issues
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|---|---|---|
| Offsetting Liabilities [Line Items] | ||
| Number of currency swaps outstanding | Bond_issues | 2 | |
| Accounts Receivable, before Allowance for Credit Loss, Current | $ 1,791 | $ 1,683 |
| Amount of letters of credit outstanding | 6 | |
| Forward Contract Derivative Asset, at Fair Value | 18 | 11 |
| Letter of Credit | ||
| Offsetting Liabilities [Line Items] | ||
| Amount of letters of credit outstanding | 517 | 566 |
| Interest Swap Collateral | ||
| Offsetting Liabilities [Line Items] | ||
| Amount of letters of credit outstanding | 411 | |
| Fair Value, Inputs, Level 2 | ||
| Offsetting Liabilities [Line Items] | ||
| Forward Contract Derivative Asset, at Fair Value | $ 18 | $ 11 |
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- Definition Fair value as of the balance sheet date of forward contract derivative assets. No definition available.
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- Definition Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Number of foreign currency exchange rate derivatives held by the entity at the reporting date. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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