BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Equity Method Investments) (Details) (Details) |
Mar. 31, 2020 |
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| Combined Metals of Chicago, LLC [Member] | Ìý |
| Schedule of Equity Method Investments [Line Items] | Ìý |
| Equity Method Investment, Ownership Percentage | 40.00% |
| Hibbing Taconite Company [Member] | Ìý |
| Schedule of Equity Method Investments [Line Items] | Ìý |
| Equity Method Investment, Ownership Percentage | 23.00% |
| Spartan Steel Coating, LLC [Member] | Ìý |
| Schedule of Equity Method Investments [Line Items] | Ìý |
| Equity Method Investment, Ownership Percentage | 48.00% |
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. 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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