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Risk Management Activities and Derivative Transactions Counterparty Credit Risk (Details)	12 Months Ended
	Sep. 30, 2023
Derivative
Two Largest Customer Percentage of Total Operating Revenue	17.00%
Moody's, A1 Rating
Derivative
Natural Gas Banking Counterparties Credit Rating	A1
Moody's, B1 Rating
Derivative
Natural Gas Banking Counterparties Credit Rating	B1
Moody's, A2 Rating
Derivative
Banking Counterparties Credit Rating	A2

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Banking Counterparties Credit Rating

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Two Largest Customer Percentage of Total Operating Revenue

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-5

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