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Litigation, Claims and Contingencies - Summary of Asbestos Claims Activity (Details) - Claim Claim in Thousands | 12 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2017
Ashland [Member] |  |  |
Asbestos claims [Roll Forward] |  |  |
Open claims - beginning of year | 53 | 54 | 57
New claims filed | 2 | 2 | 2
Claims settled | (1) | (1) | (1)
Claims dismissed | (1) | (2) | (4)
Open claims - end of year | 53 | 53 | 54
Hercules [Member] |  |  |
Asbestos claims [Roll Forward] |  |  |
Open claims - beginning of year | 13 | 12 | 15
New claims filed | 1 | 2 | 1
Claims dismissed | (1) | (1) | (4)
Open claims - end of year | 13 | 13 | 12

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Number of claims dismissed. + References No definition available. + Details
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- Definition Number of claims settled. + References No definition available. + Details
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- Definition The total number of new claims filed pertaining to a loss contingency during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349 + Details
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- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349 + Details
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- Details
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- Details
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