Short-Term Borrowings and Long-Term Debt - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Sep. 30, 2024
Debt Instrument [Line Items]
Less: current portion	$ (35,593)	$ (33,766)
Less: unamortized portion of debt issuance costs	(1,600)	(1,514)
Long-term debt, net current portion and unamortized debt issuance costs	365,070	355,906
Mortgage Facility [Member]
Debt Instrument [Line Items]
Long-term debt	402,263	391,186
Mortgage Facility [Member] \| Mortgage Facility Payable to Flagship Bank [Member]
Debt Instrument [Line Items]
Long-term debt	5,039	5,411
Mortgage Facility [Member] \| Mortgage Facility Payable to Seacoast National Bank [Member]
Debt Instrument [Line Items]
Long-term debt	14,360	15,378
Mortgage Facility [Member] \| Mortgage facility payable to Hancock Whitney Bank [Member]
Debt Instrument [Line Items]
Long-term debt	19,931	21,366
Mortgage Facility [Member] \| Mortgage Facility Payable to M&T Bank [Member]
Debt Instrument [Line Items]
Long-term debt	36,540
Term Loan [Member] \| Term loan payable to M&T Bank [Member]
Debt Instrument [Line Items]
Long-term debt	325,000	347,500
Term Loan [Member] \| Loan payable to TRANSPORT S.a.s di Taula Vittorio and C. [Member]
Debt Instrument [Line Items]
Long-term debt	$ 1,393	$ 1,531

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