DISCONTINUED OPERATIONS - Net Cash from Operating and Investing Activities (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash from operating activities	$ (578)	$ 15	$ (2,073)
Cash from investing activities	0	3,436	12,530
Climate Technologies
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash from operating activities	(578)	15	(1,314)
Cash from investing activities	0	3,436	9,475
ISE
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash from operating activities	0	0	(759)
Cash from investing activities	$ 0	$ 0	$ 3,055

Amount of cash inflow (outflow) from investing activity attributable to discontinued operation. Investing activity includes, but is not limited to, making and collecting loan, acquiring and disposing of debt and equity instruments, property, plant, and equipment, and other productive assets.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
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-Subparagraph (c)(1)
-Publisher FASB
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Amount of cash inflow (outflow) from operating activity attributable to discontinued operation. Operating activity includes, but is not limited to, transaction, adjustment, and change in value not defined as investing or financing activity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 360
-SubTopic 10
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