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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narratives (Detail) - USD ($) $ in Millions | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Summary Of Significant Accounting Policies [Line Items] |  |  |
Research and development expense | $ 118.0 | $ 107.0 | $ 105.0
Business acquisition cost | $ 6.0 | $ 33.0 | $ 6.0
Land Improvements | Minimum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 10 years |  |
Land Improvements | Maximum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 20 years |  |
Building and improvements | Minimum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 5 years |  |
Building and improvements | Maximum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 30 years |  |
Machinery and equipment | Minimum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 2 years |  |
Machinery and equipment | Maximum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 10 years |  |
Furniture and Fixtures | Minimum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 3 years |  |
Furniture and Fixtures | Maximum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Property, plant and equipment, useful life | 10 years |  |
Technology Intangible Assets | Minimum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Finite lived intangible asset useful life | 10 years |  |
Technology Intangible Assets | Maximum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Finite lived intangible asset useful life | 22 years |  |
Order backlog |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Finite lived intangible asset useful life | 1 year |  |
Order backlog | Minimum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Finite lived intangible asset useful life | 1 year |  |
Order backlog | Maximum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Finite lived intangible asset useful life | 3 years |  |
Customer Relationships | Minimum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Finite lived intangible asset useful life | 10 years |  |
Other Intangible Assets | Minimum |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Finite lived intangible asset useful life | 20 years |  |

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- Definition Amount of expense for acquisition-related cost incurred to effect business combination. Includes, but is not limited to, finder's fee; advisory, legal, accounting, valuation, and other professional and consulting fees; and general administrative cost, including cost of maintaining internal acquisition department. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479328/805-10-50-7 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 25 -Paragraph 23 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479405/805-10-25-23 + Details
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- Definition Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity. + References Reference 1: 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 2: http://www.xbrl.org/2003/role/exampleRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147476153/220-40-55-14 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 48 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482785/280-10-55-48 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 985 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481283/985-20-50-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 730 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482916/730-10-50-1 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 912 -SubTopic 730 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479532/912-730-25-1 + Details
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