Debt and Other Obligations Debt Outstanding (Details) - USD ($) $ in Millions |
Jun. 30, 2025 |
Sep. 30, 2024 |
|---|---|---|
| Short-term debt | ||
| Short-term debt, net | $ 319 | $ 1,167 |
| Current maturities of power bonds | 1,370 | 1,022 |
| Current maturities of long-term debt of variable interest entities | 48 | 37 |
| Debt, Current | 1,737 | 2,226 |
| Long-term debt | ||
| Long-term power bonds | 19,389 | 17,995 |
| Unamortized discounts, premiums, issues costs, and other | 160 | 128 |
| Total long-term debt, net | 20,880 | 18,764 |
| Total outstanding debt | 22,617 | 20,990 |
| Long-term debt of variable interest entities, net | 1,651 | 897 |
| Net exchange gain from currency transaction, noncurrent | $ 48 | $ 62 |
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- Definition Carrying value as of the balance sheet date of debt not otherwise defined (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion and excluding the unamortized discount, premiums and other. No definition available.
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- Definition Net exchange gain from currency transaction, noncurrent No definition available.
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- Definition Amount of debt and lease obligation, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of unamortized debt discount (premium) and debt issuance costs. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Represents the aggregate of total long-term debt, including current maturities and short-term debt. No definition available.
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of long-term debt classified as other, payable within one year or the operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of long-term debt classified as other, payable after one year or the operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Carrying value as of the balance sheet date of the portion of long-term, uncollateralized debt obligations due within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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