Long-Term Debt - Summary (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Long-term debt
Debt, gross	$ 640,541
Total debt, net	596,975		$ 590,683
Long-term debt, net	596,975		590,683
Accrual of payment-in-kind interest on Second Lien Credit Facility	$ 4,949
Weighted average interest rate (as a percent)	8.80%	8.00%
7.750% Senior Secured Notes due 2026
Long-term debt
Debt, gross	$ 350,000		350,000
Unamortized discount and other debt issuance costs	(5,352)		(5,594)
Total debt, net	$ 344,648		344,406
Interest rate (as a percent)	7.75%
Second Lien Facility
Long-term debt
Debt, gross	$ 204,291		199,342
Unamortized discount and other debt issuance costs	(35,726)		(36,701)
Total debt, net	168,565		162,641
Principal Amount	190,000
Exit fee	5,700
Accrual of payment-in-kind interest on Second Lien Credit Facility	8,600		3,600
4.50% Convertible Senior Notes due 2026
Long-term debt
Debt, gross	86,250		86,250
Unamortized discount and other debt issuance costs	(2,488)		(2,614)
Total debt, net	$ 83,762		$ 83,636
Interest rate (as a percent)	4.50%
ABL Credit Facility
Long-term debt
Maximum borrowing capacity	$ 45,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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