FINANCING AND FINANCIAL INSTRUMENTS - Risk management policy - Raw Materials, Freight, Energy Risks and Emission Rights (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Emission rights
Disclosure of detailed information about financial instruments [line items]
Net financial derivatives	$ 0
Level 2
Disclosure of detailed information about financial instruments [line items]
Derivative financial assets	298	$ 438
Derivative financial liabilities	(416)	(638)
Level 2 \| Total raw materials (base metals), freight, energy, emission rights
Disclosure of detailed information about financial instruments [line items]
Net financial derivatives	(56)	52
Derivative financial assets	195	172
Derivative financial liabilities	(251)	(120)
Level 2 \| Base Metals
Disclosure of detailed information about financial instruments [line items]
Net financial derivatives	11	(11)
Level 2 \| Freight
Disclosure of detailed information about financial instruments [line items]
Net financial derivatives	22	3
Level 2 \| Energy (oil, gas, electricity)
Disclosure of detailed information about financial instruments [line items]
Net financial derivatives	(89)	60
Level 2 \| Emission rights
Disclosure of detailed information about financial instruments [line items]
Net financial derivatives	$ 0	$ 0

The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2027-01-01
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- Definition

The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

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Derivative Financial Assets (Liabilities)

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