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Summary Of Significant Accounting Policies (Components Of Other Current Assets) (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Sep. 30, 2024
--- | --- | ---
Summary Of Significant Accounting Policies [Line Items] |  |
Prepayments | $ 22,810 | $ 18,463
Prepaid Property and Other Taxes | 11,703 | 14,187
Regulatory Assets | 27,656 | 38,264
Other Current Assets | 64,241 | 92,229
Federal |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Income Taxes Receivable | 0 | 8,154
State |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Income Taxes Receivable | $ 2,072 | $ 13,161

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