Summary Of Significant Accounting Policies (Schedule Of Other Accruals And Current Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023
Accounting Policies [Abstract]
Accrued Capital Expenditures	$ 75,485	$ 43,323
Regulatory Liabilities	35,770	38,105
Reserve for Gas Replacement	1,247	0
Liability for Royalty and Working Interests	25,529	17,679
Non-Qualified Benefit Plan Liability	13,052	13,052
Other	48,926	48,815
Other Accruals and Current Liabilities	$ 200,009	$ 160,974