Other Financial Information (Other Liabilities) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Sep. 30, 2022
Other Liabilities [Abstract]
Deferred income taxes	$ 2,006	$ 1,714
Pension and postretirement liabilities	452	427
Operating lease liabilities (noncurrent)	360	312
Asbestos litigation	178	205
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred income taxes	2,006	$ 1,714
Climate Technologies (excluding Therm-O-Disc)
Other Liabilities [Abstract]
Deferred income taxes	540
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred income taxes	$ 540

Amount of deferred tax liability attributable to taxable temporary differences.

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Carrying amount as of the balance sheet date of reserves for the costs of settling insured claims and costs incurred in the claims settlement process attributable to asbestos and environmental claims, before estimated recoveries from reinsurers.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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