Percentage of assets and liabilities current.

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- Definition

Percentage of net sales.

+ References

No definition available.

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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 35
-Paragraph 32
-URI http://asc.fasb.org/extlink&oid=118954474&loc=d3e32787-111569

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521

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- Definition

Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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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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Hyperinflationary Economies - Additional Information (Detail) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019 USD ($)	Sep. 30, 2019 USD ($) $ / $	Sep. 30, 2018 USD ($) $ / $	Sep. 30, 2017 USD ($)
Other Nonoperating Income (Expense) [Member]
Schedule Of Equity Method Investments [Line Items]
Foreign currency transaction gains (losses)			$ (4)	$ (4)
Maximum [Member] \| Other Nonoperating Income (Expense) [Member]
Schedule Of Equity Method Investments [Line Items]
Foreign currency transaction gains (losses)		$ 1
Argentina [Member]
Schedule Of Equity Method Investments [Line Items]
Percentage of net revenue		3.00%	2.00%
Foreign currency exchange rate, translation \| $ / $		57.32	39.70
Argentina [Member] \| Other Nonoperating Income (Expense) [Member]
Schedule Of Equity Method Investments [Line Items]
Foreign currency transaction gains (losses)		$ 2	$ 3
Argentina [Member] \| Maximum [Member]
Schedule Of Equity Method Investments [Line Items]
Percentage of assets and liabilities current		2.00%	2.00%
Venezuela [Member] \| Carbon Black Affiliate [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	49.00%
Venezuela [Member] \| Other Nonoperating Income (Expense) [Member] \| Carbon Black Affiliate [Member]
Schedule Of Equity Method Investments [Line Items]
Impairment charge	$ 11
Carbon Black Operating Entity [Member] \| Argentina [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investment, ownership percentage		100.00%