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Summary of Significant Accounting Policies - Schedule of Other Accruals and Current Liabilities (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Sep. 30, 2024
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Accounting Policies [Abstract] |  |
Accrued Capital Expenditures | $ 45,932 | $ 47,344
Regulatory Liabilities | 20,624 | 29,352
Liability for Royalty and Working Interests | 28,076 | 15,007
Pennsylvania Impact Fee | 14,923 | 9,972
Non-Qualified Benefit Plan Liability | 11,567 | 14,135
Other | 53,567 | 47,093
Other Accruals and Current Liabilities | $ 174,689 | $ 162,903

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- Definition Carrying value as of the balance sheet date of obligations incurred through that date and payable for obligations incurred for oil and gas properties with joint interest partners. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References No definition available. + Details
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- Definition Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(20)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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