DISCONTINUED OPERATIONS DISCONTINUED OPERATIONS (Narrative) (Details) (USD $)
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3 Months Ended | 12 Months Ended | |
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Mar. 31, 2015
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Mar. 31, 2014
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Dec. 31, 2014
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Canadian Entities [Member] | Ìý | Ìý | Ìý |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | Ìý | Ìý | Ìý |
Discontinued Operation, Tax Effect of Discontinued Operation |
$ 0us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_CanadianEntitiesMember |
$ 44,300,000us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_CanadianEntitiesMember |
Ìý |
Business Exit Costs |
(818,700,000)us-gaap_BusinessExitCosts1 / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_CanadianEntitiesMember |
0us-gaap_BusinessExitCosts1 / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_CanadianEntitiesMember |
Ìý |
Cost Method Investments |
0us-gaap_CostMethodInvestments / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_CanadianEntitiesMember |
Ìý | Ìý |
North American Coal [Member] | Ìý | Ìý | Ìý |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | Ìý | Ìý | Ìý |
Pension and Other Postretirement Defined Benefit Plans, Liabilities |
330,000,000us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý | Ìý |
Discontinued Operation, Tax Effect of Discontinued Operation |
100,000us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
7,200,000us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
Tangible Asset Impairment Charges |
(73,400,000)us-gaap_TangibleAssetImpairmentCharges / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý | Ìý |
Asia Pacific Iron Ore [Member] | Asia Pacific Iron Ore [Member] | Ìý | Ìý | Ìý |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | Ìý | Ìý | Ìý |
Tangible Asset Impairment Charges | Ìý | Ìý |
526,500,000us-gaap_TangibleAssetImpairmentCharges / clf_AssetgroupAxis = clf_AsiaPacificIronOreMember / clf_ReportingUnitAxis = clf_AsiaPacificIronOreMember |
Other Current Assets [Member] | Canadian Entities [Member] | Ìý | Ìý | Ìý |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | Ìý | Ìý | Ìý |
Loans, Associated Interest and Accounts Receivable recognized in Consolidated Financials at Fair Value |
112,100,000clf_LoansAssociatedInterestandAccountsReceivablerecognizedinConsolidatedFinancialsatFairValue / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherCurrentAssetsMember / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_CanadianEntitiesMember |
Ìý | Ìý |
Other Current Liabilities [Member] | Bloom Lake Group [Member] | Ìý | Ìý | Ìý |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | Ìý | Ìý | Ìý |
Contingent Liabilities recognized in Consolidated Financials |
166,100,000clf_ContingentLiabilitiesrecognizedinConsolidatedFinancials / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherCurrentLiabilitiesMember / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_BloomLakeGroupMember |
Ìý | Ìý |
Short-term Liabilities of Discontinued Operations [Member] | Canadian Entities [Member] | Ìý | Ìý | Ìý |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | Ìý | Ìý | Ìý |
Liabilities Recorded for Wholly-owned Subsidiaries of Bloom Lake Group that did not file CCAA |
51,400,000clf_LiabilitiesRecordedforWhollyownedSubsidiariesofBloomLakeGroupthatdidnotfileCCAA / us-gaap_BalanceSheetLocationAxis = clf_ShorttermLiabilitiesofDiscontinuedOperationsMember / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_CanadianEntitiesMember |
Ìý | Ìý |
Long-term Liabilities of Discontinued Operations [Member] | Canadian Entities [Member] | Ìý | Ìý | Ìý |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | Ìý | Ìý | Ìý |
Liabilities Recorded for Wholly-owned Subsidiaries of Bloom Lake Group that did not file CCAA |
$ 125,200,000clf_LiabilitiesRecordedforWhollyownedSubsidiariesofBloomLakeGroupthatdidnotfileCCAA / us-gaap_BalanceSheetLocationAxis = clf_LongtermLiabilitiesofDiscontinuedOperationsMember / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_CanadianEntitiesMember |
Ìý | Ìý |
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- Definition
Contingent Liabilities recognized in Consolidated Financials No definition available.
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Liabilities Recorded for Wholly-owned Subsidiaries of Bloom Lake Group that did not file CCAA No definition available.
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- Definition
Loans, Associated Interest and Accounts Receivable recognized in Consolidated Financials at Fair Value No definition available.
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- Definition
Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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This represents the entire liability recognized in the balance sheet that is associated with the defined benefit plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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