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Property, Plant and Equipment - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2017
Property Plant And Equipment [Line Items] |  |  |
Accelerated depreciation |  |  | $ 13
Selling, General and Administrative Expenses [Member] | Unallocated and other [Member] |  |  |
Property Plant And Equipment [Line Items] |  |  |
Accelerated depreciation | $ 1 | $ 8 | 5
Machinery and Equipment [Member] |  |  |
Property Plant And Equipment [Line Items] |  |  |
Accelerated depreciation | $ 38 |  |
Machinery and Equipment [Member] | Equity and Other Income (Expense) [Member] | Specialty Solutions [Member] |  |  |
Property Plant And Equipment [Line Items] |  |  |
Accelerated depreciation |  | $ 6 | 1
Machinery and Equipment [Member] | Cost of Sales [Member] | Functional Materials [Member] |  |  |
Property Plant And Equipment [Line Items] |  |  |
Accelerated depreciation |  |  | $ 13

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of accelerated depreciation charged against earnings associated with exit from or disposal of business activities or restructuring plan. + References No definition available. + Details
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- Details
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