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Regulatory Matters (Tables) | 12 Months Ended
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Sep. 30, 2025
Regulatory Assets and Liabilities, Other Disclosure [Abstract] |
Schedule of Regulatory Assets and Liabilities | The Company has recorded the following regulatory assets and liabilities:
| At September 30
| 2025 |  | 2024
| (Thousands)
Regulatory Assets: |  |  |
Recoverable Future Taxes (Note G) | $ | 89,247 |  |  | $ | 80,084 |
Unamortized Debt Expense (Note A) | 6,236 |  |  | 5,604 |
Other Regulatory Assets: |  |  |
Pension Costs (Note K) | 42,602 |  |  | 30,259 |
NY Rate Case Levelization and Tracking Mechanisms(1) | 28,688 |  |  | — |
Asset Retirement Obligations (Note E) | 24,634 |  |  | 21,951 |
Post-Retirement Benefit Costs (Note K) | 13,306 |  |  | 7,932 |
System Modernization / Improvement Tracker (See Regulatory Mechanisms in Note A) | 12,625 |  |  | 31,362 |
Other | 13,631 |  |  | 16,518 |
Total Long-Term Regulatory Assets | $ | 230,969 |  |  | $ | 193,710 |
Current Regulatory Assets: |  |  |
Unrecovered Purchased Gas Costs (See Regulatory Mechanisms in Note A) | 5,769 |  |  | — |
Other Current Assets: |  |  |
System Modernization / Improvement Tracker (See Regulatory Mechanisms in Note A) | 14,481 |  |  | 15,681 |
Other | 20,881 |  |  | 22,583 |
Total Regulatory Assets | $ | 272,100 |  |  | $ | 231,974 |
(1)New York Rate Case Levelization and Tracking Mechanisms were approved in accordance with Distribution Corporation’s New York rate settlement on December 19, 2024, as discussed below. The mechanisms include: (a) levelization deferral of $17.8 million which relates to a volumetric surcredit within the Company’s delivery adjustment charge that minimizes customer bill impacts, (b) uncollectible expense tracker of $9.8 million, which tracks and reconciles the actual uncollectible expense to the amounts recovered in base rates and, (c) property tax tracker of $1.1 million, which represents the amount deferred between actual property taxes incurred and the level included in customer rates.
| At September 30
| 2025 |  | 2024
| (Thousands)
Regulatory Liabilities: |  |  |
Taxes Refundable to Customers (Note G) | $ | 306,335 |  |  | $ | 305,645 |
Cost of Removal Regulatory Liability | 307,659 |  |  | 292,477 |
Other Regulatory Liabilities: |  |  |
Post-Retirement Benefit Costs (Note K) | 108,714 |  |  | 135,399 |
Environmental Site Remediation Costs (Note L) | 1,800 |  |  | 5,390 |
Other | 11,430 |  |  | 10,663 |
Total Long-Term Regulatory Liabilities | $ | 735,938 |  |  | $ | 749,574 |
Current Regulatory Liabilities: |  |  |
Amounts Payable to Customers (See Regulatory Mechanisms in Note A) | 968 |  |  | 42,720 |
Other Current and Accrued Liabilities: |  |  |
Post-Retirement Benefit Costs (Note K) | 5,800 |  |  | 5,800 |
Other | 14,824 |  |  | 23,552 |
Total Regulatory Liabilities | $ | 757,530 |  |  | $ | 821,646 |

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- Definition Detailed information about assets created when regulatory agencies permit public utilities to defer certain costs included in rate-setting to the balance sheet and detailed information about liabilities 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. + References No definition available. + Details
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- References No definition available. + Details
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