Supporting Financial Information - Debt Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Debt Instrument [Line Items]
Long-term debt	$ 203,377
Less: unamortized deferred financing costs	(8,930)	$ (1,584)
Long-term portion of debt obligations, net of deferred financing costs	194,447	20,416
Less: current portion of debt obligations, net of deferred financing costs	(28,505)	0
Long-term portion of debt obligations, net of deferred financing costs	165,942	20,416
Secured Debt
Debt Instrument [Line Items]
Long-term debt	186,438	22,000
Less: current portion of debt obligations, net of deferred financing costs	(28,505)	0
Secured Revolving Line of Credit
Debt Instrument [Line Items]
Long-term debt	16,939	$ 0
Revolving Line of Credit \| Secured Debt
Debt Instrument [Line Items]
Long-term debt	$ 186,400

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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