Other Financial Information (Accrued Expenses) (Details) - USD ($) $ in Millions	6 Months Ended
Mar. 31, 2023	Sep. 30, 2022
Accrued Liabilities and Other Liabilities [Abstract]
Customer advances (contract liabilities)	$ 940	$ 751
Employee compensation	445	523
Accrued Income Taxes, Current	$ 390	125
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued expenses
Operating lease liabilities (current)	$ 132	128
Product warranty	91	$ 84
InSinkErator [Member]
Discontinued Operation, Tax Effect of Discontinued Operation	660
Taxes Payable, Current	330
Climate Technologies (excluding Therm-O-Disc)
Discontinued Operation, Tax Effect of Discontinued Operation	$ 245

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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