ACQUISITIONS - Consideration (Details) $ / shares in Units, $ / shares in Units, $ in Millions, $ in Millions |
Nov. 01, 2024
USD ($)
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Nov. 01, 2024
CAD ($)
$ / shares
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Nov. 18, 2021
USD ($)
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Dec. 31, 2024
shares
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Nov. 01, 2024
USD ($)
$ / shares
shares
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Dec. 31, 2023
shares
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Dec. 31, 2022
shares
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Dec. 31, 2021
shares
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| Business Acquisition [Line Items] | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Common shares, outstanding (in shares) | Ìý | Ìý | Ìý | 493,948,905 | Ìý | 504,886,773 | Ìý | Ìý |
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | Ìý | Ìý | Ìý | 200,000 | Ìý | 500,000 | 600,000 | 1,000,000.0 |
| Stelco Holdings Inc | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Business Acquisition [Line Items] | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Total cash consideration | $ 2,450 | $ 3,418 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Total share exchange consideration | 343 | 343 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Total debt consideration | $ | Ìý | Ìý | Ìý | Ìý | $ 415 | Ìý | Ìý | Ìý |
| Total purchase consideration | $ | Ìý | Ìý | $ 3,208 | Ìý | Ìý | Ìý | Ìý | Ìý |
| Common shares, outstanding (in shares) | Ìý | Ìý | Ìý | Ìý | 54,448,388 | Ìý | Ìý | Ìý |
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | Ìý | Ìý | Ìý | Ìý | 2,516,415 | Ìý | Ìý | Ìý |
| Total consideration shares | Ìý | Ìý | Ìý | Ìý | 56,964,803 | Ìý | Ìý | Ìý |
| Foreign Currency Exchange Rate, Translation | Ìý | Ìý | Ìý | Ìý | 0.7168 | Ìý | Ìý | Ìý |
| Share price (in dollars per share) | (per share) | Ìý | $ 60.00 | Ìý | Ìý | $ 13.27 | Ìý | Ìý | Ìý |
| Business Acquisition, Shares Exchange Ratio | 0.454 | 0.454 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
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- Definition Business Acquisition, Shares Exchange Ratio No definition available.
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- Definition Business Combination, Consideration Transferred, Debt Consideration No definition available.
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- Definition Total consideration shares No definition available.
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination. No definition available.
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The method of determining the fair value of the equity interests of the acquirer, including the number of instruments or interests issued or issuable in consideration for the business combination. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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