Short-Term Borrowings and Long-Term Debt - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2026	Sep. 30, 2025
Debt Instrument [Line Items]
Less: current portion	$ (35,593)	$ (35,593)
Less: unamortized portion of debt issuance costs	(1,039)	(1,368)
Long-term debt, net current portion and unamortized debt issuance costs	338,730	356,235
Mortgage Facility [Member]
Debt Instrument [Line Items]
Long-term debt	375,362	393,196
Mortgage Facility [Member] \| Mortgage Facility Payable to Flagship Bank [Member]
Debt Instrument [Line Items]
Long-term debt	4,667	4,915
Mortgage Facility [Member] \| Mortgage Facility Payable to Seacoast National Bank [Member]
Debt Instrument [Line Items]
Long-term debt	13,341	14,020
Mortgage Facility [Member] \| Mortgage facility payable to Hancock Whitney Bank [Member]
Debt Instrument [Line Items]
Long-term debt	18,496	19,452
Mortgage Facility [Member] \| Mortgage Facility Payable To M&T Bank [Member]
Debt Instrument [Line Items]
Long-term debt	35,170	36,083
Term Loan [Member] \| Term loan payable to M&T Bank [Member]
Debt Instrument [Line Items]
Long-term debt	302,500	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	$ 1,188	$ 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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