Other Financial Information (Other Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Other Liabilities [Abstract]
Pension and postretirement liabilities	$ 790	$ 769
Deferred income taxes	411	261
Operating lease liabilities (noncurrent)	398	373
Asbestos litigation	$ 276	$ 295

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

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