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Details of Selected Financial Statement Captions - Other Current Liabilities (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Sep. 30, 2024
--- | --- | ---
Balance Sheet Related Disclosures [Abstract] |  |
Customer credit balances and deposits | $ 56,185 | $ 62,085
Accrued employee costs | 69,062 | 64,141
Deferred gas costs | 6,879 | 9,142
Operating lease liabilities (See Note 7) | 45,010 | 34,340
Accrued interest | 122,459 | 106,116
Liabilities from risk management activities | 6,339 | 7,324
Taxes payable | 237,965 | 215,857
Pension and postretirement liabilities | 6,122 | 4,622
Regulatory cost of removal obligation | 108,558 | 99,217
APT annual adjustment mechanism | 68,094 | 35,924
Regulatory excess deferred taxes (See Note 15) | 72,792 | 79,686
Other | 36,092 | 32,166
Total | $ 835,557 | $ 750,620

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