Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Allowance for credit losses
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation allowances and reserves, beginning balance	$ 237	$ 59
Additions (Reductions) Charged to Expense	(90)	194
Additions (Reductions) Charged to Other Accounts	0	0
Deductions	(30)	(16)
Valuation allowances and reserves, ending balance	117	237
Inventory valuation accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation allowances and reserves, beginning balance	2,164	3,337
Additions (Reductions) Charged to Expense	489	(304)
Additions (Reductions) Charged to Other Accounts	0	0
Deductions	80	(869)
Valuation allowances and reserves, ending balance	2,733	2,164
Inventory LIFO reserve
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation allowances and reserves, beginning balance	9,634	9,940
Additions (Reductions) Charged to Expense	862	(306)
Additions (Reductions) Charged to Other Accounts	0	0
Deductions	0	0
Valuation allowances and reserves, ending balance	10,496	9,634
Deferred tax valuation allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation allowances and reserves, beginning balance	9,112	6,977
Additions (Reductions) Charged to Expense	2,000	2,534
Additions (Reductions) Charged to Other Accounts	(212)	(399)
Deductions	0	0
Valuation allowances and reserves, ending balance	10,900	9,112
Workers’ compensation reserve
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation allowances and reserves, beginning balance	559	912
Additions (Reductions) Charged to Expense	(49)	285
Additions (Reductions) Charged to Other Accounts	0	0
Deductions	(207)	(638)
Valuation allowances and reserves, ending balance	$ 303	$ 559

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column B))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column E))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-4

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Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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