Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2021	Sep. 30, 2021
Debt Instrument [Line Items]
Total debt	$ 741,515	$ 754,943
Less unamortized deferred financing fees	(11,272)	(11,738)
Total net debt	730,243	743,205
Current portion of debt	(13,296)	(12,775)
Total long‑term debt	$ 716,947	730,430
Securitization Facility, due April 1, 2024
Debt Instrument [Line Items]
Debt , interest rate, effective percentage	1.35%
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	0.10%
2021 Revolving Credit Facility, due April 2026
Debt Instrument [Line Items]
Total debt	$ 27,269	$ 37,268
Debt , interest rate, effective percentage	2.33%
Debt instrument, basis spread on variable rate	2.20%	2.25%
Interest payable	$ 269	$ 268
2021 Revolving Credit Facility, due April 2026 \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.13%
Securitization Facility, due April 1, 2024
Debt Instrument [Line Items]
Total debt	$ 144,168	150,061
Interest payable	68	61
Equipment Financing, due September 30, 2023 to July 5, 2029, interest rates ranging from 3.13% to 8.07% \| Equipment Financings
Debt Instrument [Line Items]
Total debt	97,081	93,375
Notes Payable, due July 31, 2023
Debt Instrument [Line Items]
Total debt	347	402
2021 Term Loan
Debt Instrument [Line Items]
Total debt	$ 472,650	$ 473,837
Debt , interest rate, effective percentage	2.63%
Debt instrument, basis spread on variable rate	2.50%
Interest payable	$ 25
2021 Term Loan \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.13%
Minimum \| Equipment Financing, due September 30, 2023 to July 5, 2029, interest rates ranging from 3.13% to 8.07% \| Equipment Financings
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	3.13%
Maximum \| Equipment Financing, due September 30, 2023 to July 5, 2029, interest rates ranging from 3.13% 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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