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DERIVATIVE INSTRUMENTS AND HEDGING (Details) |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jul. 12, 2024 USD ($) | Sep. 30, 2024 USD ($) MMBtu MWh | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) MMBtu MWh | Sep. 30, 2023 USD ($) | Dec. 31, 2023 MWh MMBtu
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |
Reclassification of net losses |  |  |  | $ 97,000,000 |  |
Changes in fair value of foreign currency contracts, net |  | $ (7,000,000) | $ 0 | (7,000,000) | $ 0 |
Stelco Holdings Inc |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |
Expected enterprise value of acquisition | $ 2,500,000,000 |  |  |  |  |
Other current assets |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value |  | $ 3,000,000 |  | $ 3,000,000 |  |
Commodity Contract | Natural Gas |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |
Notional Amount | MMBtu |  | 157,430,000 |  | 157,430,000 |  | 168,590,000
Commodity Contract | Electricity |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |
Notional Amount | MWh |  | 3,499,413 |  | 3,499,413 |  | 3,501,898
Foreign Exchange Option | Canada, Dollars |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |
Derivative, Notional Amount |  | $ 1,500,000,000 |  | $ 1,500,000,000 |  |

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