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Basis of Presentation - Additional Information (Detail)
3 Months Ended
Mar. 31, 2023
Aluminum Segment [Member]  
Basis Of Presentation [Line Items]  
Ownership interest in joint venture 55.00%
AWAC [Member] | Alumina Limited [Member]  
Basis Of Presentation [Line Items]  
Non-controlling interest, ownership percentage 40.00%
AWAC [Member] | Alcoa Corporation [Member]  
Basis Of Presentation [Line Items]  
Ownership interest percentage 60.00%