Inventories - Additional Information (Detail) - Immaterial Reclassification $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)
Inventory [Line Items]
Increase (decrease) in finished goods	$ (9)
Increase (decrease) in work in process	172
Increase (decrease) in bauxite and alumina	$ (163)

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.

No definition available.

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