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Variable Interest Entities (Details) - USD ($) $ in Millions | 12 Months Ended | 348 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2053 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2052 | Sep. 30, 2013 | Sep. 30, 2012
Liabilities |  |  |  |  |  |  |
Current maturities of long-term debt of variable interest entities issued at par |  | $ 35 | $ 39 |  |  |  |
Liabilities, Current |  | 4,873 | 4,645 |  |  |  |
Other long-term liabilities |  | 1,211 | 1,485 |  |  |  |
Long-term debt of variable interest entities, net |  | 933 | 968 |  |  |  |
VIE Financing |  |  |  |  |  |  |
Face Amount |  | $ 40 |  |  |  | $ 360 |
Rate of Return SHLLC |  | 7.00% |  |  |  |  |
Accrued interest |  | $ 9 | 10 |  |  |  |
Minimum payments on membership interests subject to mandatory redemption, due in next twelve months |  | 1 |  |  |  |  |
Minimum payments on membership interests subject to mandatory redemption, due in year two |  | 1 |  |  |  |  |
Minimum payments on membership interests subject to mandatory redemption, due in year three |  | 1 |  |  |  |  |
Minimum payments on membership interests subject to mandatory redemption, due in year four |  | 1 |  |  |  |  |
Minimum payments on membership interests subject to mandatory redemption, due in year five |  | 1 |  |  |  |  |
Minimum payments on membership interests subject to mandatory redemption, due thereafter |  | 13 |  |  |  |  |
Other Long-term Debt, Maturity, Year One |  | 35 |  |  |  |  |
Other Long-term Debt, Maturity, Year Two |  | 37 |  |  |  |  |
Other Long-term Debt, Maturity, Year Three |  | 39 |  |  |  |  |
Other Long-term Debt, Maturity, Year Four |  | 40 |  |  |  |  |
Other Long-term Debt, Maturity, Year Five |  | 42 |  |  |  |  |
Other Long-term Debt, Maturity, Year Six |  | 781 |  |  |  |  |
Long-term debt of variable interest entities (including current maturities) |  | 927 | 989 |  |  |  |
Amount of letters of credit outstanding |  | 6 |  |  |  |  |
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net |  | 126 | 124 |  |  |  |
Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |
VIE Financing |  |  |  |  |  |  |
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net |  | 6 |  |  |  |  |
Portion at Other than Fair Value Measurement [Member] |  |  |  |  |  |  |
VIE Financing |  |  |  |  |  |  |
Long-term debt of variable interest entities (including current maturities) |  | 968 | 1,007 |  |  |  |
Lagoon Creek [Member] |  |  |  |  |  |  |
VIE Financing |  |  |  |  |  |  |
Amortization of reacquired rights |  | 3 |  |  |  |  |
Lagoon Creek [Member] | Scenario, Forecast |  |  |  |  |  |  |
VIE Financing |  |  |  |  |  |  |
Amortization of reacquired rights | $ 2 |  |  |  | $ 5 |  |
Letter of Credit |  |  |  |  |  |  |
VIE Financing |  |  |  |  |  |  |
Amount of letters of credit outstanding |  | 535 | 704 |  |  |  |
SCCG |  |  |  |  |  |  |
VIE Financing |  |  |  |  |  |  |
Debt and Lease Obligation |  |  |  |  |  | $ 400 |
Holdco |  |  |  |  |  |  |
VIE Financing |  |  |  |  |  |  |
Face Amount |  |  |  |  |  |  | $ 100
JSCCG |  |  |  |  |  |  |
VIE Financing |  |  |  |  |  |  |
Face Amount |  |  |  |  |  |  | 900
Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |
Liabilities |  |  |  |  |  |  |
Liabilities, Current |  | 45 | 51 |  |  |  |
Other long-term liabilities |  | 17 | 18 |  |  |  |
VIE Financing |  |  |  |  |  |  |
Accounts Payable and Accrued Liabilities |  | 1 | 2 |  |  |  |
Liabilities |  | 995 | 1,037 |  |  |  | $ 1,000
Interest Expense |  | $ 48 | $ 50 | $ 52 |  |  |

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