Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Total debt	$ 271,622	$ 273,122
Less: current portion	(6,250)	(6,250)
Total long-term debt	265,372	266,872
3.00% Convertible Senior Notes Due 2025
Debt Instrument [Line Items]
Total debt	155,066	151,791
Total long-term debt	155,066
Senior Credit Facilities
Debt Instrument [Line Items]
Total debt	116,556	$ 121,331
Less: current portion	(6,250)
Total long-term debt	$ 110,306

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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