Annual report [Section 13 and 15(d), not S-K Item 405]

ACQUISITIONS - Consideration (Details)

v3.25.0.1
ACQUISITIONS - Consideration (Details)
$ / shares in Units, $ / shares in Units, $ in Millions, $ in Millions
Nov. 01, 2024
USD ($)
Nov. 01, 2024
CAD ($)
$ / shares
Nov. 18, 2021
USD ($)
Dec. 31, 2024
shares
Nov. 01, 2024
USD ($)
$ / shares
shares
Dec. 31, 2023
shares
Dec. 31, 2022
shares
Dec. 31, 2021
shares
Business Acquisition [Line Items]                
Common shares, outstanding (in shares)       493,948,905   504,886,773    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number       200,000   500,000 600,000 1,000,000.0
Stelco Holdings Inc                
Business Acquisition [Line Items]                
Total cash consideration $ 2,450 $ 3,418            
Total share exchange consideration 343 343            
Total debt consideration | $         $ 415      
Total purchase consideration | $     $ 3,208          
Common shares, outstanding (in shares)         54,448,388      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number         2,516,415      
Total consideration shares         56,964,803      
Foreign Currency Exchange Rate, Translation         0.7168      
Share price (in dollars per share) | (per share)   $ 60.00     $ 13.27      
Business Acquisition, Shares Exchange Ratio 0.454 0.454