Other Financial Information (Other Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Sep. 30, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Pension assets	$ 673	$ 591
Asbestos-related insurance receivables	118	124
Deferred income taxes	$ 83	$ 74

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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