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Details of Selected Financial Statement Captions - Accounts Payable and Accrued Liabilities (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Sep. 30, 2024
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Balance Sheet Related Disclosures [Abstract] |  |
Trade accounts payable | $ 380,999 | $ 341,948
Accrued gas payable | 37,073 | 19,125
Accrued liabilities | 88,444 | 84,324
Total | $ 506,516 | $ 445,397

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- Definition Sum of the carrying values as of the balance sheet date of obligations incurred through that date, including liabilities incurred and payable to vendors for goods and services received, taxes, interest, rent and utilities, compensation costs, payroll taxes and fringe benefits (other than pension and postretirement obligations), contractual rights and obligations, and statutory obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(15)(5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(15)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 + 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(15)(5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 + Details
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