Summary Of Significant Accounting Policies (Reclassification Out Of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Reclassification Adjustments out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Operating Revenues	$ 525,361	$ 658,859
Total Before Income Tax	176,107	227,241
Income Tax Expense	(43,087)	(57,552)
Net Income Available for Common Stock	133,020	169,689
Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustments out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Total Before Income Tax	19,708	(159,342)
Income Tax Expense	(5,468)	43,571
Net Income Available for Common Stock	14,240	(115,771)
Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) | Commodity Contracts | Gains and Losses on Derivative Financial Instruments
Reclassification Adjustments out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Operating Revenues	19,755	(159,162)
Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) | Foreign Currency Contracts | Gains and Losses on Derivative Financial Instruments
Reclassification Adjustments out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Operating Revenues	$ (47)	$ (180)