Short-Term Borrowings and Long-Term Debt - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2026	Sep. 30, 2025
Debt Instrument [Line Items]
Less: current portion	$ (27,525)	$ (35,593)
Less: unamortized portion of debt issuance costs	(1,666)	(1,368)
Long-term debt, net current portion and unamortized debt issuance costs	335,172	356,235
Mortgage Facility [Member]
Debt Instrument [Line Items]
Long-term debt	364,363	393,196
Mortgage Facility [Member] \| Mortgage Facility Payable to Flagship Bank [Member]
Debt Instrument [Line Items]
Long-term debt	4,543	4,915
Mortgage Facility [Member] \| Mortgage Facility Payable to Seacoast National Bank [Member]
Debt Instrument [Line Items]
Long-term debt	13,003	14,020
Mortgage Facility [Member] \| Mortgage facility payable to Hancock Whitney Bank [Member]
Debt Instrument [Line Items]
Long-term debt	18,017	19,452
Mortgage Facility [Member] \| Mortgage Facility Payable To M&T Bank [Member]
Debt Instrument [Line Items]
Long-term debt	30,588	36,083
Term Loan [Member] \| Term loan payable to M&T Bank [Member]
Debt Instrument [Line Items]
Long-term debt	297,017	317,500
Term Loan [Member] \| Loan payable to TRANSPORT S.a.s di Taula Vittorio and C. [Member]
Debt Instrument [Line Items]
Long-term debt	$ 1,195	$ 1,226

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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