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SEGMENT REPORTING - Depreciation, Depletion and Amortization and Capital Additions By Segment (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Segment Reporting Information [Line Items] |  |  |
Depreciation, depletion and amortization | $ 308 | $ 85 | $ 89
Depreciation, Depletion and Amortization excluding Depreciation, Amortization and Depletion expense for Discontinued Operations |  |  | 74
Property, Plant and Equipment, Additions | 483 | 690 | 395
Steelmaking [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Depreciation, depletion and amortization | 276 | 80 | 68
Property, Plant and Equipment, Additions | 436 | 687 | 393
Other businesses |  |  |
Segment Reporting Information [Line Items] |  |  |
Depreciation, depletion and amortization | 27 | 0 | 0
Property, Plant and Equipment, Additions | 45 | 0 | 0
Corporate and Other Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Depreciation, depletion and amortization | 5 | 5 | 6
Property, Plant and Equipment, Additions | $ 2 | $ 3 | $ 2

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- References No definition available. + Details
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- Definition The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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- Definition Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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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. + References No definition available. + Details
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