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Litigation, Claims and Contingencies - Summary of Components of Environmental Remediation Expense Included within Selling, General and Administrative Expense (Parenthetical) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Environmental Expense And Liabilities [Abstract] |  |  |  |
Net expense relates to divested businesses | $ 5 | $ 3 | $ 7 | $ 4

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- References No definition available. + Details
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