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Summary Of Significant Accounting Policies (Components Of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2025 | Mar. 31, 2024
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |  |
Other Comprehensive Gains and Losses Before Reclassifications | $ (152,786) | $ 51,418 | $ (191,899) | $ 188,099
Amounts Reclassified From Other Comprehensive Income (Loss) | 5,964 | (43,459) | (15,600) | (57,699)
Gains and Losses on Derivative Financial Instruments |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |  |
Beginning balance | (4,878) | 127,064 | 55,799 | 4,623
Other Comprehensive Gains and Losses Before Reclassifications | (152,786) | 51,418 | (191,899) | 188,099
Amounts Reclassified From Other Comprehensive Income (Loss) | 5,964 | (43,459) | (15,600) | (57,699)
Ending balance | (151,700) | 135,023 | (151,700) | 135,023
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 | (76,153) | 67,381 | (15,476) | (55,060)
Ending balance | $ (222,975) | $ 75,340 | $ (222,975) | $ 75,340

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