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The amount of dividends that the company has declared but not yet paid.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
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Period Type:	instant

The amount of dividends paid by the entity on ordinary shares. [Refer: Ordinary shares [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of dividends paid to non-controlling interests. [Refer: Non-controlling interests]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2024-01-01
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The amount of dividends recognised as distributions to non-controlling interests. [Refer: Non-controlling interests]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount, per share, of dividends recognised as distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The increase (decrease) in equity through changes in ownership interests in subsidiaries that do not result in loss of control. [Refer: Total for all subsidiaries [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The number of shares authorised.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The number of shares issued by the entity, for which full payment has been received.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The proportion of ownership interests in a subsidiary held by non-controlling interests. [Refer: Total for all subsidiaries [member]; Non-controlling interests]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
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The decrease in equity resulting from the purchase of treasury shares. [Refer: Treasury shares]

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Authorised Share Capital

No definition available.

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Minimum Percentage Post-Dividend Annual Free Cash Flow

No definition available.

Name:	mt_MinimumPercentagePostDividendAnnualFreeCashFlow
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Number Of Installments Of Dividend Payments

No definition available.

Name:	mt_NumberOfInstallmentsOfDividendPayments
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Stock Repurchased During Period Shares1

No definition available.

Name:	mt_StockRepurchasedDuringPeriodShares1
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Treasury Share Repurchase Program, Authorised Number of Shares

No definition available.

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Treasury Shares Held

No definition available.

Name:	mt_TreasurySharesHeld
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Treasury Stock Acquired, Average Cost Per Share1

No definition available.

Name:	mt_TreasuryStockAcquiredAverageCostPerShare1
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Number of shares authorized to be purchased under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

No definition available.

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Name:	srt_ShareRepurchaseProgramAxis=mt_A85MillionSharesProgramMay2023Member
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