Other Financial Information (Accrued Expenses) (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2022	Sep. 30, 2022
Accrued Liabilities and Other Liabilities [Abstract]
Customer advances (contract liabilities)	$ 901	$ 751
Employee compensation	$ 372	523
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued expenses
Operating lease liabilities (current)	$ 131	128
Product warranty	89	84
Accrued Income Taxes, Current	1,080	$ 125
InSinkErator [Member]
Discontinued Operation, Tax Effect of Discontinued Operation	660
Climate Technologies (excluding Therm-O-Disc)
Discontinued Operation, Tax Effect of Discontinued Operation	$ 275

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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