Other Financial Information (Other Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019
Other Liabilities [Abstract]
Pension and postretirement liabilities	$ 774	$ 775
Operating lease liabilities (noncurrent)	361	0
Deferred income taxes	329	327
Asbestos litigation	$ 310	$ 313

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, with jurisdictional netting and classified as noncurrent.

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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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