v3.25.2
REVENUE - Disclosure of revenue disaggregated by product line (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Disaggregation of Revenue [Line Items]        
Total revenue by product line $ 2,103 $ 1,932 $ 4,082 $ 3,812
Aerospace rolled products        
Disaggregation of Revenue [Line Items]        
Total revenue by product line 267 262 534 548
Transportation, industry, defense and other rolled products        
Disaggregation of Revenue [Line Items]        
Total revenue by product line 200 212 368 396
Packaging rolled products        
Disaggregation of Revenue [Line Items]        
Total revenue by product line 912 729 1,780 1,400
Automotive rolled products        
Disaggregation of Revenue [Line Items]        
Total revenue by product line 295 320 586 631
Specialty and other thin-rolled products        
Disaggregation of Revenue [Line Items]        
Total revenue by product line 26 28 50 60
Automotive extruded products        
Disaggregation of Revenue [Line Items]        
Total revenue by product line 249 250 483 513
Other extruded products        
Disaggregation of Revenue [Line Items]        
Total revenue by product line $ 154 $ 131 $ 281 $ 264