Venezuela - Additional Information (Detail) $ in Millions	6 Months Ended
Mar. 31, 2017 USD ($) VEB / $	Mar. 31, 2016 USD ($)
Schedule Of Equity Method Investments [Line Items]
Operating affiliate investment	$ 13
Conversion of Bolivars to USD \| VEB / $	709
Subsidiaries
Schedule Of Equity Method Investments [Line Items]
Cash dividends received from subsidiary	$ 2	$ 2
Venezuela [Member] \| Carbon Black Affiliate [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	49.00%

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section S99
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Amount of Equity in net profit and loss for the period. Give totals for each group. If operations of any controlled companies are different in character from those of the company, group such affiliates (1) within divisions and (2) by type of activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14(Column C))
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611322-123010

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-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611322-123010

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-Name Accounting Standards Codification
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- Definition

Dividends received on equity and other investments during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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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.

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No definition available.

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