COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Loss Contingencies [Line Items] | |||
| Loans to and accounts receivables from the Canadian Entities | $ 51.6 | $ 48.6 | |
| Contingent claims | 55.6 | 0.0 | |
| Short-term loan receivable | 7.7 | ||
| LOSS FROM DISCONTINUED OPERATIONS, net of tax | (18.7) | (19.9) | $ (892.1) |
| Accrual for Environmental Loss Contingencies | 2.9 | 2.8 | |
| Michigan Electricity Matters [Member] | |||
| Loss Contingencies [Line Items] | |||
| Loss Contingency Accrual | 12.3 | $ 13.6 | |
| Wabush Scully Mine Sale [Member] | |||
| Loss Contingencies [Line Items] | |||
| LOSS FROM DISCONTINUED OPERATIONS, net of tax | $ 31.4 | ||
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- Definition Loans to and accounts receivables from the Canadian Entities No definition available.
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- Definition Reserve for unasserted claims in CCAA No definition available.
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- Definition Short-term loan receivable No definition available.
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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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 loss contingency liability. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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