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Regulatory Assets and Liabilities Regulatory Assets and Liabilities (Tables) | 12 Months Ended
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Sep. 30, 2025
Regulatory Assets and Liabilities Disclosure [Abstract] |
Regulatory Assets and Liabilities | Components of regulatory assets and regulatory liabilities are summarized in the table below.
Regulatory Assets and Liabilities At September 30 (in millions)
| 2025 |  | 2024
Current regulatory assets |  |  |
Unrealized losses on commodity contract derivatives | $ | 59 |  |  | $ | 102 |
Unrealized losses on interest rate derivatives | 57 |  |  | 54 |
Fuel cost adjustment receivable | — |  |  | 35 |
Other current regulatory assets | 11 |  |  | — |
Total current regulatory assets | 127 |  |  | 191 |
Non-current regulatory assets |  |  |
Non-nuclear decommissioning costs | 5,563 |  |  | 6,187 |
Retirement benefit plans deferred costs | 1,531 |  |  | 1,979 |
Unrealized losses on interest rate derivatives | 316 |  |  | 447 |
Environmental compliance and remediation costs | 308 |  |  | 215 |
Nuclear decommissioning costs | 149 |  |  | 362 |
Unrealized losses on commodity contract derivatives | 12 |  |  | 64 |
Other non-current regulatory assets | 168 |  |  | 154 |
Total non-current regulatory assets | 8,047 |  |  | 9,408 |
Total regulatory assets | $ | 8,174 |  |  | $ | 9,599 |
Current regulatory liabilities |  |  |
Fuel cost adjustment tax equivalents | $ | 203 |  |  | $ | 169 |
Unrealized gains on commodity contract derivatives | 14 |  |  | 5 |
Fuel cost adjustment payable | 11 |  |  | — |
Total current regulatory liabilities | 228 |  |  | 174 |
Non-current regulatory liabilities |  |  |
Retirement benefit plans deferred credits | 131 |  |  | 81 |
Unrealized gains on commodity contract derivatives | 10 |  |  | 2 |
Total non-current regulatory liabilities | 141 |  |  | 83 |
Total regulatory liabilities | $ | 369 |  |  | $ | 257 |

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- Definition Tabular disclosure of assets and liabilities that are created when regulatory agencies permit public utilities to defer certain costs included in rate-setting to the balance sheet or that result from rate actions of a regulator. Rate actions of a regulator can impose a liability on a regulated enterprise resulting in a regulatory liability. Regulatory liabilities can result from obligations to make refunds to customers or deferral of gains that will be credited to customers in future periods + References No definition available. + Details
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- References No definition available. + Details
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