PENSIONS AND OTHER POSTRETIREMENT BENEFITS (Weighted-Average Assumptions Used to Determine Net Benefit Cost) (Details)
|
12 Months Ended | 2 Months Ended | 10 Months Ended | ||
---|---|---|---|---|---|
Dec. 31, 2014
|
Dec. 31, 2013
|
Dec. 31, 2012
|
Dec. 31, 2012
|
Oct. 31, 2012
|
|
Pension Benefits [Member] | United States [Member] | |||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||||
Discount rate |
4.57%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
3.70%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
4.28%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
||
Expected return on plan assets |
8.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
8.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
8.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
||
Pension Benefits [Member] | Canada [Member] | |||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||||
Discount rate |
4.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_CanadaMember |
3.75%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_CanadaMember |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_CanadaMember |
||
Expected return on plan assets |
7.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_CanadaMember |
7.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_CanadaMember |
7.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_CanadaMember |
||
Other Benefits [Member] | United States [Member] | |||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||||
Discount rate |
4.57%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
3.70%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
|||
Expected return on plan assets |
7.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
8.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
8.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
||
Other Benefits [Member] | Canada [Member] | |||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||||
Discount rate |
4.75%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_CanadaMember |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_CanadaMember |
4.25%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_RegionReportingInformationByRegionAxis = clf_CanadaMember |
||
Hourly [Member] | Pension Benefits [Member] | |||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||||
Rate of compensation increase |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_TypeofCompensationAxis = clf_HourlyMember |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_TypeofCompensationAxis = clf_HourlyMember |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_TypeofCompensationAxis = clf_HourlyMember |
||
Salary [Member] | Pension Benefits [Member] | |||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||||
Rate of compensation increase |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_TypeofCompensationAxis = clf_SalaryMember |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_TypeofCompensationAxis = clf_SalaryMember |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / clf_TypeofCompensationAxis = clf_SalaryMember |
||
Salary [Member] | Other Benefits [Member] | |||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||||
Rate of compensation increase |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_TypeofCompensationAxis = clf_SalaryMember |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_TypeofCompensationAxis = clf_SalaryMember |
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember / clf_TypeofCompensationAxis = clf_SalaryMember |
||
Salaried Plan [Member] | United States [Member] | |||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||||
Discount rate |
4.28%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / clf_PlanTypeAxis = clf_SalariedPlanMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
||||
Hourly Plan [Member] | United States [Member] | |||||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||||
Discount rate |
3.51%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / clf_PlanTypeAxis = clf_HourlyPlanMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
4.28%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / clf_PlanTypeAxis = clf_HourlyPlanMember / clf_RegionReportingInformationByRegionAxis = clf_UnitedStatesMember |
X | ||||||||||
- Definition
The interest rate used to adjust for the time value of money. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Definition
An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Definition
Expected rate of compensation increases (for pay-related plans). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|