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ACQUISITIONS - Preliminary Purchase Price Allocation (Details) - USD ($) $ in Millions | 11 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024 | Nov. 01, 2024
Business Combination [Line Items] |  |  |
Goodwill | $ 1,796 | $ 1,768 |
Stelco Holdings Inc |  |  |
Business Combination [Line Items] |  |  |
Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent | 341 |  | $ 341
Business Combination, Recognized Asset Acquired, Receivable, Current | 104 |  | 104
Business Combination, Recognized Asset Acquired, Inventory, Current | 715 |  | 726
Business Combination, Recognized Asset Acquired, Other Asset, Current | 106 |  | 107
Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment | 1,282 |  | 1,286
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived | 1,025 |  | 1,025
Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent | 249 |  | 250
Business Combination, Recognized Liability Assumed, Accounts Payable, Current | (212) |  | (212)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accrued Employment Costs | (29) |  | (29)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accrued Expenses | (7) |  | (6)
Business Combination, Recognized Liability Assumed, Other Liability, Current | (71) |  | (71)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Non-Current Liabilities, Pension and OPEB liabilities | (14) |  | (14)
Business Combination, Recognized Liability Assumed, Deferred Tax Liability | (439) |  | (449)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Non-Current Liabilities, Asset retirement and environmental obligations | (20) |  | (20)
Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent | (611) |  | (616)
Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less) | 2,419 |  | 2,422
Goodwill | 789 |  | 786
Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill | 3,208 |  | $ 3,208
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Cash and Cash Equivalents | 0 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Accounts Receivable | 0 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory | (11) |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other Current Assets | (1) |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment | (4) |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles | 0 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other Noncurrent Assets | (1) |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Accounts Payable | 0 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Accrued Employment Cost | 0 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Accrued Expenses | (1) |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other Current Liabilities | 0 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Pension and OPEB Liability Non-current | 0 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Income Taxes | 10 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Asset retirement and environmental obligations | 0 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other Non-Current Liabilities | 5 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Net Identifiable Assets Acquired | (3) |  |
Goodwill, Measurement Period Adjustment | 3 |  |
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred | $ 0 |  |

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