Other Financial Information (Accrued Expenses) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021
Accrued Liabilities and Other Liabilities [Abstract]
Customer advances (contract liabilities)	$ 851	$ 730
Employee compensation	$ 428	690
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued expenses
Operating lease liabilities (current)	$ 152	155
Product warranty	$ 136	$ 146

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

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

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Indicates line item in statement of financial position that includes current operating lease liability.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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