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DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES -Long-lived assets, including definite intangible assets (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Description Of Business And Summary Of Significant Accounting Policies [Line Items] |  |  |
Depreciation, depletion and amortization, nonproduction | $ 39,734 | $ 37,901 | $ 43,056
Accumulated capitalized interest costs | 3,489 | 2,228 | 1,463
Original cost of fully depreciated property plant and equipment | $ 265,931 |  |
Minimum |  |  |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] |  |  |
Long-lived assets, useful life | 8 years |  |
Minimum | Building and Building Improvements |  |  |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 25 years |  |
Minimum | Machinery and equipment |  |  |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 2 years |  |
Maximum |  |  |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] |  |  |
Long-lived assets, useful life | 25 years |  |
Maximum | Building and Building Improvements |  |  |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 40 years |  |
Maximum | Machinery and equipment |  |  |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 15 years |  |
Selling, general and administrative expenses |  |  |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] |  |  |
Depreciation | $ 17,007 | $ 16,510 | $ 17,598

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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147476153/220-40-55-18 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147476153/220-40-55-11 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 24 -Publisher FASB -URI https://asc.fasb.org/1943274/2147476153/220-40-55-24 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-12 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-6 + Details
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