GOODWILL AND INTANGIBLE ASSETS - Schedule of Intangible Assets Acquired (Detail) $ in Millions	12 Months Ended
Sep. 30, 2026 USD ($)
Intangible Asset, Finite-Lived, Acquired [Line Items]
Intangible assets subject to amortization	$ 1,751
intangible Assets, Acquired During the Period	1,965
Trademarks and trade names
Intangible Asset, Finite-Lived, Acquired [Line Items]
Intangible assets not subject to amortization	214
Technology
Intangible Asset, Finite-Lived, Acquired [Line Items]
Intangible assets subject to amortization	$ 766
Technology \| Minimum
Intangible Asset, Finite-Lived, Acquired [Line Items]
Amortization Period (in years)	10 years
Technology \| Maximum
Intangible Asset, Finite-Lived, Acquired [Line Items]
Amortization Period (in years)	20 years
Order backlog
Intangible Asset, Finite-Lived, Acquired [Line Items]
Intangible assets subject to amortization	$ 26
Order backlog \| Minimum
Intangible Asset, Finite-Lived, Acquired [Line Items]
Amortization Period (in years)	1 year
Order backlog \| Maximum
Intangible Asset, Finite-Lived, Acquired [Line Items]
Amortization Period (in years)	3 years
Customer relationships
Intangible Asset, Finite-Lived, Acquired [Line Items]
Intangible assets subject to amortization	$ 959
Customer relationships \| Minimum
Intangible Asset, Finite-Lived, Acquired [Line Items]
Amortization Period (in years)	10 years

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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 of increase in finite-lived intangible asset acquired in business combination, asset acquisition, and from joint venture formation. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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Amount of increase in indefinite-lived asset acquired in business combination, asset acquisition, and from joint venture formation. Excludes goodwill.

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