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Long-Term Debt, Net - Summary of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021	Feb. 18, 2020
Debt Instrument [Line Items]
Debt issuance costs, net	$ (2,554)	$ (3,599)
Total long-term debt, net of issuance costs	287,020	200,605
Line of Credit \| Revolving lines of credit to banks under the Senior Secured Credit Facility
Debt Instrument [Line Items]
Long-term debt	185,017	104,396
Exchangeable Notes \| 1.0% Exchangeable Senior Notes due 2025
Debt Instrument [Line Items]
Long-term debt	104,557	$ 99,808
Stated interest rate (percent)			1.00%
Debt issuance costs, net	$ (1,939)