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Regulatory Assets and Liabilities (Tables) | 9 Months Ended
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Jun. 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 (in millions)
| At June 30, 2025 |  | At September 30, 2024
Current regulatory assets |  |  |
Unrealized losses on commodity derivatives | $ | 22 |  |  | $ | 102 |
Unrealized losses on interest rate derivatives | 51 |  |  | 54 |
Fuel cost adjustment receivable | 79 |  |  | 35 |
Total current regulatory assets | 152 |  |  | 191 |
Non-current regulatory assets |  |  |
Non-nuclear decommissioning costs | 6,135 |  |  | 6,187 |
Retirement benefit plans deferred costs | 1,915 |  |  | 1,979 |
Nuclear decommissioning costs | 276 |  |  | 362 |
Unrealized losses on interest rate derivatives | 321 |  |  | 447 |
Environmental compliance and remediation costs | 313 |  |  | 215 |
Unrealized losses on commodity derivatives | 8 |  |  | 64 |
Other non-current regulatory assets | 169 |  |  | 154 |
Total non-current regulatory assets | 9,137 |  |  | 9,408 |
Total regulatory assets | $ | 9,289 |  |  | $ | 9,599 |
Current regulatory liabilities |  |  |
Fuel cost adjustment tax equivalents | $ | 189 |  |  | $ | 169 |
Unrealized gains on commodity derivatives | 13 |  |  | 5 |
Total current regulatory liabilities | 202 |  |  | 174 |
Non-current regulatory liabilities |  |  |
Retirement benefit plans deferred credits | 68 |  |  | 81 |
Unrealized gains on commodity derivatives | 17 |  |  | 2 |
Total non-current regulatory liabilities | 85 |  |  | 83 |
Total regulatory liabilities | $ | 287 |  |  | $ | 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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