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, classified as current.

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

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Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2022	Sep. 30, 2021
Debt Instrument [Line Items]
Total debt	$ 945,374		$ 945,374	$ 754,943
Less unamortized deferred financing fees	(10,812)		(10,812)	(11,738)
Total net debt	934,562		934,562	743,205
Current portion of debt	(14,219)		(14,219)	(12,775)
Total long‑term debt	$ 920,343		$ 920,343	730,430
Prime Rate \| Rate three
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.50%
Prime Rate \| Rate four
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.95%
Securitization Facility, due April 1, 2024
Debt Instrument [Line Items]
Debt , interest rate, effective percentage	1.70%		1.70%
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			0.45%
2021 Revolving Credit Facility, due April 2026
Debt Instrument [Line Items]
Total debt	$ 221,106		$ 221,106	37,268
Debt instrument, basis spread on variable rate		2.25%	1.95%
Interest payable	106		$ 106	268
2021 Revolving Credit Facility, due April 2026 \| Rate one
Debt Instrument [Line Items]
Total debt	$ 187,000		$ 187,000
Debt , interest rate, effective percentage	2.20%		2.20%
2021 Revolving Credit Facility, due April 2026 \| Rate two
Debt Instrument [Line Items]
Total debt	$ 34,000		$ 34,000
Debt , interest rate, effective percentage	4.45%		4.45%
2021 Revolving Credit Facility, due April 2026 \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			0.25%
Securitization Facility, due April 1, 2024
Debt Instrument [Line Items]
Total debt	$ 150,078		$ 150,078	150,061
Interest payable	78		78	61
Equipment Financing, due September 30, 2023 to July 31, 2029, interest rates ranging from 3.13% to 8.07% \| Equipment Financings
Debt Instrument [Line Items]
Total debt	102,752		102,752	93,375
Notes Payable, due July 31, 2023 (4)
Debt Instrument [Line Items]
Total debt	0		0	402
2021 Term Loan
Debt Instrument [Line Items]
Total debt	$ 471,438		$ 471,438	473,837
Debt , interest rate, effective percentage	2.75%		2.75%
Debt instrument, basis spread on variable rate			2.50%
Interest payable	$ 0		$ 0	$ 25
2021 Term Loan \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			0.25%
Minimum \| Equipment Financing, due September 30, 2023 to July 31, 2029, interest rates ranging from 3.13% to 8.07% \| Equipment Financings
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	3.13%		3.13%
Maximum \| Equipment Financing, due September 30, 2023 to July 31, 2029, interest rates ranging from 3.13% to 8.07% \| Equipment Financings
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	8.07%		8.07%