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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narratives (Detail) - USD ($) $ in Millions	12 Months Ended
	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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Summary Of Significant Accounting Policies [Line Items]

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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

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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-Topic 220
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