Other Financial Information (Accrued Expenses & Other Liabilities) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Sep. 30, 2017
Other Financial Information [Line Items]
Employee compensation	$ 606	$ 531
Customer advanced payments	533	505
Product warranty	130	120
Pension and postretirement liabilities	661	664
Deferred income taxes	262	425
Asbestos litigation	333	340
Other	690	551
Total	1,946	$ 1,980
Asbestos Issue [Member]
Other Financial Information [Line Items]
Recorded Third-Party Environmental Recoveries Receivable	$ 131

Other Financial Information [Line Items]

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The current portion of money or property received from customers which is either to be returned upon satisfactory contract completion or applied to customer receivables in accordance with the terms of the contract or the understandings.

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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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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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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Amount of liability, recognized in statement of financial position, for pension, other postretirement and postemployment benefits, classified as noncurrent.

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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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