Summary Of Significant Accounting Policies (Reclassification Out Of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Operating Revenues	$ 717,261	$ 701,720	$ 1,376,119	$ 1,248,277
Income Before Income Taxes	190,817	224,786	418,059	402,076
Income Tax Expense	(49,937)	(57,458)	(107,489)	(102,356)
Net Income Available for Common Stock	140,880	167,328	310,570	299,720
Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Income Before Income Taxes	(18,940)	(130,221)	(178,281)	(292,809)
Income Tax Expense	5,208	35,641	48,779	80,141
Net Income Available for Common Stock	(13,732)	(94,580)	(129,502)	(212,668)
Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member] | Commodity Contracts [Member] | Gains And Losses On Derivative Financial Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Operating Revenues	(18,768)	(130,271)	(177,930)	(292,899)
Foreign Currency Contracts [Member] | Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member] | Gains And Losses On Derivative Financial Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Operating Revenues	$ (172)	$ 50	$ (351)	$ 90