Summary Of Significant Accounting Policies (Schedule Of Other Accruals And Current Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Sep. 30, 2024
Summary Of Significant Accounting Policies [Line Items]
Accrued Capital Expenditures	$ 52,852	$ 47,344
Regulatory Liabilities	24,235	29,352
Reserve for Gas Replacement	1,316	0
Liability for Royalty and Working Interests	23,673	15,007
Non-Qualified Benefit Plan Liability	14,135	14,135
Other	50,949	57,065
Other Accruals and Current Liabilities	172,409	162,903
Federal
Summary Of Significant Accounting Policies [Line Items]
Federal Income Taxes Payable	$ 5,249	$ 0