Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2022	Sep. 30, 2022
Debt Instrument [Line Items]
Total debt	$ 881,187	$ 890,673
Less unamortized deferred financing fees	(9,396)	(9,873)
Total net debt	871,791	880,800
Current portion of debt	(19,322)	(17,266)
Total long‑term debt	$ 852,469	863,534
Securitization Facility, due April 1, 2024
Debt Instrument [Line Items]
Debt , interest rate, effective percentage	5.64%
Securitization Facility, due April 1, 2024 \| Rate three
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.25%
Securitization Facility, due April 1, 2024 \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	4.39%
2021 Term Loan
Debt Instrument [Line Items]
Total debt	$ 467,900	469,063
Debt , interest rate, effective percentage	6.38%
Debt instrument, basis spread on variable rate	2.25%
Interest payable	$ 25	0
2021 Term Loan \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	4.13%
2021 Revolving Credit Facility, due April 2026
Debt Instrument [Line Items]
Total debt	$ 136,502	151,254
Interest payable	502	254
2021 Revolving Credit Facility, due April 2026 \| Rate one
Debt Instrument [Line Items]
Total debt	$ 136,000
Debt , interest rate, effective percentage	6.33%
2021 Revolving Credit Facility, due April 2026 \| Rate two
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.20%
2021 Revolving Credit Facility, due April 2026 \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	4.13%
Securitization Facility, due April 1, 2024
Debt Instrument [Line Items]
Total debt	$ 150,282	150,201
Interest payable	282	201
Equipment Financing, due September 30, 2023 to September 30, 2032, interest rates ranging from 3.59% to 8.07% \| Equipment Financings
Debt Instrument [Line Items]
Total debt	$ 126,503	$ 120,155
Minimum \| Equipment Financing, due September 30, 2023 to September 30, 2032, interest rates ranging from 3.59% to 8.07% \| Equipment Financings
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	3.59%
Maximum \| Equipment Financing, due September 30, 2023 to September 30, 2032, interest rates ranging from 3.59% to 8.07% \| Equipment Financings
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	8.07%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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 of unamortized debt discount (premium) and debt issuance costs.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, including portion classified as current.

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