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Commitments and Contingencies - Additional Information (Detail) | 9 Months Ended |
--- | --- | ---
Jun. 30, 2018 USD ($) claimants | Jun. 30, 2017 USD ($) | Sep. 30, 2017 USD ($) claimants
Respirator Liabilities [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Number of claimants | claimants | 35,000 |  | 37,000
Respirator reserve | $ 17,000,000 |  | $ 18,000,000
Cash payments for respirator reserves |  | $ 3,000,000 |
Maximum [Member] | Respirator Liabilities [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Cash payments for respirator reserves | 1,000,000 |  |
Environmental Matters [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Reserved for environmental matters | 15,000,000 |  | $ 12,000,000
Cash payments for environmental reserves | $ 2,000,000 | $ 2,000,000 |

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- Definition Number of claimants in pending cases asserting claims in connection with respiratory products. + References No definition available. + Details
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- Definition The estimated aggregate amount of losses related to respirator liability claims as of the balance sheet date. + References No definition available. + Details
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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 + Details
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