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Summary Of Significant Accounting Policies (Components Of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |  |
Other Comprehensive Gains and Losses Before Reclassifications | $ 108,818 | $ (15,850) | $ (83,082) | $ 172,249
Amounts Reclassified From Other Comprehensive Income (Loss) | (1,650) | (54,440) | (17,249) | (112,139)
Gains and Losses on Derivative Financial Instruments |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |  |
Beginning balance | (151,700) | 135,023 | 55,799 | 4,623
Other Comprehensive Gains and Losses Before Reclassifications | 108,818 | (15,850) | (83,082) | 172,249
Amounts Reclassified From Other Comprehensive Income (Loss) | (1,650) | (54,440) | (17,249) | (112,139)
Ending balance | (44,532) | 64,733 | (44,532) | 64,733
Funded Status of the Pension and Other Post-Retirement Benefit Plans |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |  |
Beginning balance | (71,275) | (59,683) | (71,275) | (59,683)
Other Comprehensive Gains and Losses Before Reclassifications | 0 | 0 | 0 | 0
Amounts Reclassified From Other Comprehensive Income (Loss) | 0 | 0 | 0 | 0
Ending balance | (71,275) | (59,683) | (71,275) | (59,683)
Accumulated Other Comprehensive Income (Loss) |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |  |
Beginning balance | (222,975) | 75,340 | (15,476) | (55,060)
Ending balance | $ (115,807) | $ 5,050 | $ (115,807) | $ 5,050

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