Long-term Debt and Line of Credit - Summary of Long-term Debt and Line of Credit (Details) - USD ($)	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Debt Instrument [Line Items]
Total debt outstanding	$ 430,306,000	$ 465,140,000
Less current portion (net of current debt issuance costs)	(7,874,000)	(29,324,000)
Less unamortized portion of debt issuance costs	(7,498,000)	(7,377,000)
Long-term debt, net of current portion and unamortized debt issuance costs	414,934,000	428,439,000
Term Note Payable on August 9, 2027
Debt Instrument [Line Items]
Total debt outstanding	$ 375,469,000	$ 428,313,000
Debt instrument, interest rate, stated percentage	7.85%	7.53%
Revolving Note Payable
Debt Instrument [Line Items]
Total debt outstanding	$ 51,150,000	$ 30,000,000
Debt instrument, interest rate, stated percentage	7.75%	7.50%
Line of credit facility, maximum borrowing capacity	$ 65,000,000.0
Note Payable Due On September 2028
Debt Instrument [Line Items]
Total debt outstanding	$ 2,561,000	$ 3,645,000
Note Payable Due On September 2028 \| Minimum
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	0.00%
Debt instrument, periodic payment	$ 200,000
Note Payable Due On September 2028 \| Maximum
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	10.80%
Debt instrument, periodic payment	$ 3,100,000
Note Payable 5.5% Due on December 1, 2023
Debt Instrument [Line Items]
Total debt outstanding	$ 0	2,056,000
Debt instrument, interest rate, stated percentage	5.50%
Note payable, 4.0% due on December 1, 2024
Debt Instrument [Line Items]
Total debt outstanding	$ 1,126,000	$ 1,126,000
Debt instrument, interest rate, stated percentage	4.00%

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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