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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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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Acquisitions - Additional Information (Detail) - USD ($) $ in Millions		1 Months Ended	6 Months Ended	12 Months Ended
	Apr. 01, 2020	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Business Acquisition [Line Items]
Businesses acquisition, net of cash acquired					$ 92	$ 3
Assumed debt repaid				$ 222	$ 410	$ 75
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
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