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v3.24.3

Subsequent Events (Details) - USD ($) $ in Millions | Oct. 02, 2024 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2013 | Sep. 30, 2012
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Debt Instrument, Redemption [Line Items] |  |  |  |  |
Non-current regulatory liabilities |  | $ 83 | $ 107 |  |
Regulatory assets |  | 9,408 | 5,566 |  |
Face Amount |  | 40 |  | $ 360 |
Long-term debt of variable interest entities, net |  | 897 | 933 |  |
Current maturities of long-term debt of variable interest entities issued at par |  | 37 | 35 |  |
JACTG |  |  |  |  |
Debt Instrument, Redemption [Line Items] |  |  |  |  |
Face Amount | $ 720 |  |  |  |
Long-term debt of variable interest entities, net | 791 |  |  |  |
Current maturities of long-term debt of variable interest entities issued at par | 9 |  |  |  |
Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |
Debt Instrument, Redemption [Line Items] |  |  |  |  |
Debt and Lease Obligation | 800 |  |  |  |
Holdco |  |  |  |  |
Debt Instrument, Redemption [Line Items] |  |  |  |  |
Face Amount | $ 80 |  |  |  | $ 100
Unrealized gains/losses on commodity derivatives |  |  |  |  |
Debt Instrument, Redemption [Line Items] |  |  |  |  |
Regulatory assets |  | 64 | 52 |  |
Unrealized gains/losses on commodity derivatives |  |  |  |  |
Debt Instrument, Redemption [Line Items] |  |  |  |  |
Non-current regulatory liabilities |  | $ 2 | $ 12 |  |

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