Expected production commencement year.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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No definition available.

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

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No definition available.

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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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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Amount of liability recognized arising from contingent consideration in a business combination.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Acquisitions - Additional Information (Detail) - USD ($) $ in Millions		1 Months Ended		6 Months Ended	12 Months Ended
	Apr. 01, 2020	Jun. 30, 2020	Sep. 30, 2018	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Business Acquisition [Line Items]
Businesses acquisition, net of cash acquired					$ 92	$ 3	$ 64
Assumed debt repaid					410	75	$ 251
NSCC Carbon (Jiangsu) Co. Ltd [Member]
Business Acquisition [Line Items]
Acquisition date			Sep. 30, 2018
Business acquisition, purchase price			$ 8
Expected production commencement year			2022
Transition related costs					2	$ 4
Shenzhen Sanshun Nano New Materials Co., Ltd [Member]
Business Acquisition [Line Items]
Business acquisition, purchase price	$ 100
Business acquisition, cash consideration	84
Businesses acquisition, net of cash acquired	1
Business acquisition, assumed debt	13
Assumed debt repaid		$ 13
Business combination future contingent consideration milestone payment	3
Business acquisition, revenue				$ 12
Acquisition and integration costs				$ 3	$ 3
Shenzhen Sanshun Nano New Materials Co., Ltd [Member] \| Developed Technologies [Member]
Business Acquisition [Line Items]
Finite-lived intangible assets	$ 9
Intangible assets amortization period	10 years
Shenzhen Sanshun Nano New Materials Co., Ltd [Member] \| Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangible assets	$ 4
Intangible assets amortization period	20 years
Shenzhen Sanshun Nano New Materials Co., Ltd [Member] \| Trademarks [Member]
Business Acquisition [Line Items]
Finite-lived intangible assets	$ 2
Intangible assets amortization period	10 years