Commitments and Contingencies - Additional Information (Detail)	6 Months Ended
Mar. 31, 2017 USD ($) claimants	Mar. 31, 2016 USD ($)	Sep. 30, 2016 USD ($) claimants
Respirator Liabilities [Member]
Loss Contingencies [Line Items]
Number of claimants \| claimants	37,000		38,000
Respirator reserve	$ 19,000,000		$ 21,000,000
Cash payments for respirator reserves	2,000,000	$ 2,000,000
Environmental Matters [Member]
Loss Contingencies [Line Items]
Reserved for environmental matters	13,000,000		$ 14,000,000
Environmental Matters [Member] \| Maximum [Member]
Loss Contingencies [Line Items]
Cash payments for environmental reserves	$ 1,000,000	$ 1,000,000

Number of claimants in pending cases asserting claims in connection with respiratory products.

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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

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- Definition

Amount of cash outflow to settle environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.Y.Q2)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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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.

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- Definition

Amount of cash outflow reducing loss contingency liability.

+ References

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