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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.

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Useful life of finite-lived intangible asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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Amount, before tax, of realized gain (loss) from foreign currency transaction.

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Amount of valuation reserve for inventory.

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Useful life of property, plant, and equipment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection.

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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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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narratives (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2024
Summary Of Significant Accounting Policies [Line Items]
Research and development expense	$ 151	$ 118	$ 107
Provision for potentially obsolete or slow-moving inventory	357	270
Business acquisition cost	25	6	33
Income Statement Location [Axis]: us-gaap:CostOfGoodsAndServicesSold
Summary Of Significant Accounting Policies [Line Items]
Foreign currency losses or (gains) recognized in cost of sales	$ 2	$ 10	$ 20
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 \| 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
Customer Relationships \| Maximum
Summary Of Significant Accounting Policies [Line Items]
Finite lived intangible asset useful life	20 years
Other Intangible Assets
Summary Of Significant Accounting Policies [Line Items]
Finite lived intangible asset useful life	20 years