BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions |
3 Months Ended | |
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Dec. 31, 2020 |
Sep. 30, 2020 |
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Business Acquisition [Line Items] | Ìý | Ìý |
Common shares, par value | Ìý | $ 0.125 |
Forecast [Member] | ArcelorMittal USA [Member] | Ìý | Ìý |
Business Acquisition [Line Items] | Ìý | Ìý |
Business Combination, Consideration Transferred | $ 1,400 | Ìý |
Payments to Acquire Businesses, Gross | $ 505 | Ìý |
Forecast [Member] | ArcelorMittal USA [Member] | Common Stock [Member] | Ìý | Ìý |
Business Acquisition [Line Items] | Ìý | Ìý |
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | 78,186,671 | Ìý |
Forecast [Member] | ArcelorMittal USA [Member] | Series B Participating Redeemable Preferred Stock [Member] | Ìý | Ìý |
Business Acquisition [Line Items] | Ìý | Ìý |
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | 583,273 | Ìý |
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- Definition Number of shares of equity interests issued or issuable to acquire entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. 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 Face amount or stated value per share of common stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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