Commitments And Contingencies (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Sep. 30, 2024
Other Commitments [Line Items]
Estimated minimum liability for environmental remediation	$ 3,700
Other Regulatory Liabilities	140,828	$ 151,452
Environmental Site Remediation Costs
Other Commitments [Line Items]
Other Regulatory Liabilities	$ 2,700

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant