Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Debt Instrument [Line Items]
Total debt	$ 270,577	$ 271,343
Less: current portion	(9,375)	(6,250)
Total long-term debt	261,202	265,093
3.00% Convertible Senior Notes Due 2025
Debt Instrument [Line Items]
Total debt	159,691	156,205
Total long-term debt	159,691
Senior Credit Facilities
Debt Instrument [Line Items]
Total debt	110,886	$ 115,138
Less: current portion	(9,375)
Total long-term debt	$ 101,511

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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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