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Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021	Apr. 01, 2021
Debt Instrument [Line Items]
Total debt	$ 890,673	$ 754,943
Less unamortized deferred financing fees	(9,873)	(11,738)	$ (2,375)
Total net debt	880,800	743,205
Current portion of debt	(17,266)	(12,775)
Total long‑term debt	863,534	730,430
2021 Term Loan
Debt Instrument [Line Items]
Total debt	469,063	473,837
2021 Revolving Credit Facility, due April 2026
Debt Instrument [Line Items]
Total debt	151,254	37,268
Securitization Facility, due April 1, 2024
Debt Instrument [Line Items]
Total debt	150,201	150,061
Notes Payable due July 2023
Debt Instrument [Line Items]
Total debt	0	402
Equipment Financings \| Equipment Financing
Debt Instrument [Line Items]
Total debt	$ 120,155	$ 93,375
Minimum \| Equipment Financings \| Equipment Financing
Debt Instrument [Line Items]
Interest Rate	3.59%
Maximum \| Equipment Financings \| Equipment Financing
Debt Instrument [Line Items]
Interest Rate	8.07%