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Long-Term Debt - Net (Details) - USD ($) $ in Thousands	Nov. 25, 2020	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019
Long-term debt
Debt, gross		$ 691,240
Total debt, net		667,584	$ 681,129
Less short-term borrowings and current portion of long-term debt		(81,314)	(88,189)
Long-term debt, net		$ 586,270	592,940
Weighted average interest rate (as a percent)		8.00%		8.80%
Term Loan A due 2020
Long-term debt
Debt, gross		$ 41,969	48,844
Unamortized discount and other debt issuance costs		(97)	(433)
Total debt, net	$ 42,000	$ 41,872	48,411
Interest rate (as a percent)		6.00%
Term Loan B due 2022
Long-term debt
Debt, gross		$ 563,021	572,857
Unamortized discount and other debt issuance costs		(20,573)	(23,278)
Total debt, net		$ 542,448	549,579
Interest rate (as a percent)		6.38%
4.50% Convertible Senior Notes due 2026
Long-term debt
Debt, gross		$ 86,250	86,250
Unamortized discount and other debt issuance costs		(2,986)	(3,111)
Total debt, net		$ 83,264	$ 83,139
Interest rate (as a percent)		4.50%
Revolving Credit Facility due 2020
Long-term debt
Maximum borrowing capacity		$ 125,000