XML 171 R143.htm IDEA: XBRL DOCUMENT
v2.4.1.9

SUBSEQUENT EVENTS Narrative (Details) (USD $) | 12 Months Ended | 11 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2013 | Jan. 26, 2015 | Sep. 30, 2014 | May 31, 2015 | Jan. 22, 2015
Subsequent Event [Line Items] |  |  |  |  |  |  |
Debt Instrument, Par Value | $ 4,144,800,000 clf_DebtInstrumentParValue |  | $ 4,814,800,000 clf_DebtInstrumentParValue |  |  |  |
Estimated Capital Costs to Develop Bloom Lake Phase II | 1,200,000,000 clf_EstimatedCapitalCoststoDevelopBloomLakePhaseII |  |  |  |  |  |
Elimination of Dividend [Member] |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Elimination of Dividend |  |  |  | $ 0.15 clf_EliminationofDividend / us-gaap_SubsequentEventTypeAxis = clf_EliminationofDividendMember |  |  |
Free Cash Flow Due to Quarterly Dividend Elimination |  |  |  | 92,000,000 clf_FreeCashFlowDuetoQuarterlyDividendElimination / us-gaap_SubsequentEventTypeAxis = clf_EliminationofDividendMember |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Debt Instrument, Par Value | 1,125,000,000 clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember |  | 1,750,000,000 clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember |  | 1,250,000,000 clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember |  |
Revolving Credit Facility [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Debt Instrument, Face Amount, Subsequent Event - Revolving Credit Facility Amendment |  |  |  |  |  | 750,000,000 clf_DebtInstrumentFaceAmountSubsequentEventRevolvingCreditFacilityAmendment / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_SubsequentEventTypeAxis = us-gaap_RevolvingCreditFacilityMember | 900,000,000 clf_DebtInstrumentFaceAmountSubsequentEventRevolvingCreditFacilityAmendment / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_SubsequentEventTypeAxis = us-gaap_RevolvingCreditFacilityMember
Permit Costs and Expenses in connection with Canadian Restructuring EBITDA Add back- Subsequent Event - Revolving Credit Facility Amendment |  | $ 75,000,000 clf_PermitCostsandExpensesinconnectionwithCanadianRestructuringEBITDAAddbackSubsequentEventRevolvingCreditFacilityAmendment / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_SubsequentEventTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  |  |  |
Limit on Dividend per Share - Subsequent Event - Revolving Credit Facility Amendment |  | $ 0.01 clf_LimitonDividendperShareSubsequentEventRevolvingCreditFacilityAmendment / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_SubsequentEventTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  |  |  |

X
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- Definition Debt Instrument, Par Value + References No definition available. + Details
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- Definition Estimated Capital Costs to Developing Bloom Lake Phase II + References No definition available. + Details
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- Definition Permit Costs and Expenses in connection with Canadian Restructuring EBITDA Add back - Subsequent Event - Revolving Credit Facility Amendment + References No definition available. + Details
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