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DISCONTINUED OPERATIONS Discontinued Operations, Items Measured at Fair Value on a Non-Recurring Basis - North American Coal (Details) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | 12 Months Ended |
|---|---|---|
|
Mar. 31, 2015
|
Dec. 31, 2014
|
|
| Discontinued Operations, Items Measured at Fair Value on a Non-Recurring Basis [Line Items] | Ìý | Ìý |
| Assets, Fair Value Disclosure, Nonrecurring | $ 397.2us-gaap_AssetsFairValueDisclosureNonrecurring | $ 79.4us-gaap_AssetsFairValueDisclosureNonrecurring |
| Impairment Charges | 269.5clf_ImpairmentCharges | 644.7clf_ImpairmentCharges |
| North American Coal [Member] | Ìý | Ìý |
| Discontinued Operations, Items Measured at Fair Value on a Non-Recurring Basis [Line Items] | Ìý | Ìý |
| Property, Plant, and Equipment, Fair Value Disclosure |
20.4us-gaap_PropertyPlantAndEquipmentFairValueDisclosure / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
| Tangible Asset Impairment Charges |
(73.4)us-gaap_TangibleAssetImpairmentCharges / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
| Assets, Fair Value Disclosure, Nonrecurring |
20.4us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
| Impairment Charges |
(73.4)clf_ImpairmentCharges / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
| Fair Value, Inputs, Level 1 [Member] | Ìý | Ìý |
| Discontinued Operations, Items Measured at Fair Value on a Non-Recurring Basis [Line Items] | Ìý | Ìý |
| Assets, Fair Value Disclosure, Nonrecurring |
0us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
0us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
| Fair Value, Inputs, Level 1 [Member] | North American Coal [Member] | Ìý | Ìý |
| Discontinued Operations, Items Measured at Fair Value on a Non-Recurring Basis [Line Items] | Ìý | Ìý |
| Property, Plant, and Equipment, Fair Value Disclosure |
0us-gaap_PropertyPlantAndEquipmentFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
| Assets, Fair Value Disclosure, Nonrecurring |
0us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
| Fair Value, Inputs, Level 2 [Member] | Ìý | Ìý |
| Discontinued Operations, Items Measured at Fair Value on a Non-Recurring Basis [Line Items] | Ìý | Ìý |
| Assets, Fair Value Disclosure, Nonrecurring |
397.2us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
0us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
| Fair Value, Inputs, Level 2 [Member] | North American Coal [Member] | Ìý | Ìý |
| Discontinued Operations, Items Measured at Fair Value on a Non-Recurring Basis [Line Items] | Ìý | Ìý |
| Property, Plant, and Equipment, Fair Value Disclosure |
0us-gaap_PropertyPlantAndEquipmentFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
| Assets, Fair Value Disclosure, Nonrecurring |
0us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
| Fair Value, Inputs, Level 3 [Member] | Ìý | Ìý |
| Discontinued Operations, Items Measured at Fair Value on a Non-Recurring Basis [Line Items] | Ìý | Ìý |
| Assets, Fair Value Disclosure, Nonrecurring |
0us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
79.4us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
| Fair Value, Inputs, Level 3 [Member] | North American Coal [Member] | Ìý | Ìý |
| Discontinued Operations, Items Measured at Fair Value on a Non-Recurring Basis [Line Items] | Ìý | Ìý |
| Property, Plant, and Equipment, Fair Value Disclosure |
20.4us-gaap_PropertyPlantAndEquipmentFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
| Assets, Fair Value Disclosure, Nonrecurring |
$ 20.4us-gaap_AssetsFairValueDisclosureNonrecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = clf_NorthAmericanCoalMember |
Ìý |
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- Definition
Impairment charges including, but not limited to, impairment charges related to intangible and tangible assets, investment, and goodwill. No definition available.
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- Definition
This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. No definition available.
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- Definition
Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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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