Acquisitions - Additional Information (Detail) - USD ($) $ in Millions		12 Months Ended
Feb. 28, 2022	Sep. 30, 2022
Business Acquisition [Line Items]
Businesses acquisition, net of cash acquired		$ 9
Gain on bargain purchase of a business		24
Tokai Carbon Group Tianjin Co
Business Acquisition [Line Items]
Business acquisition, purchase price	$ 9
Business acquisition, cash consideration	14
Businesses acquisition, net of cash acquired	$ 5
Tokai Carbon Group Tianjin Co \| Accounts Payable and Accrued Liabilities [Member]
Business Acquisition [Line Items]
Gain on bargain purchase of a business		$ 24
Tokai Carbon Group Tianjin Co \| Tokai Carbon's Registered Capital [Member]
Business Acquisition [Line Items]
Business acquisition, ownership percentage	100.00%

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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