根据第13或15(d)条提交的季度报告

环境和关闭矿井义务（关闭矿井义务摘要）（详情）

v2.4.1.9
环境和矿山关闭义务（矿山关闭义务摘要）（详细信息）（美元）
除非另有说明，单位为百万
2015年3月31日
2014年12月31日
或有损失〔分项〕    
环境 3.7美元us-gaap_AccrualForEnvironmentalLossContingencies 5.5美元us-gaap_AccrualForEnvironmentalLossContingencies
矿山复垦和结算负债，流动和非流动 165.3clf_MineReclamationAndClosingLiabilityCurrentAndNoncurrent 165.3clf_MineReclamationAndClosingLiabilityCurrentAndNoncurrent
环境和矿山关闭的全部义务 169.0clf_EnvironmentalLossContingencyAndMineReclamationAndClosingLiabilityCurrentAndNoncurrent 170.8clf_EnvironmentalLossContingencyAndMineReclamationAndClosingLiabilityCurrentAndNoncurrent
小电流部分 3.4clf_EnvironmentalLossContingencyAndMineReclamationAndClosingLiabilityCurrent 5.2clf_EnvironmentalLossContingencyAndMineReclamationAndClosingLiabilityCurrent
长期的环境和矿山关闭义务 165.6clf_EnvironmentalLossContingencyAndMineReclamationAndClosingLiabilityNoncurrent 165.6clf_EnvironmentalLossContingencyAndMineReclamationAndClosingLiabilityNoncurrent
皇冠体育官网铁矿石[成员]bbb100拥有或经营的设施[成员]    
或有损失〔分项〕    
矿山复垦和结算负债，流动和非流动 121.8clf_MineReclamationAndClosingLiabilityCurrentAndNoncurrent
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= clf_OwnedOrOperatingFacilitiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= clf_USIronOreMember 		120.9clf_MineReclamationAndClosingLiabilityCurrentAndNoncurrent
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= clf_OwnedOrOperatingFacilitiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= clf_USIronOreMember
亚太地区铁矿石[成员]|自有或营运设施[成员]    
或有损失〔分项〕    
矿山复垦和结算负债，流动和非流动 20.3clf_MineReclamationAndClosingLiabilityCurrentAndNoncurrent
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= clf_OwnedOrOperatingFacilitiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= clf_AsiaPacificIronOreMember 		21.5clf_MineReclamationAndClosingLiabilityCurrentAndNoncurrent
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= clf_OwnedOrOperatingFacilitiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= clf_AsiaPacificIronOreMember
LTV钢铁矿业公司[成员]|以前拥有或经营的设施[成员]    
或有损失〔分项〕    
矿山复垦和结算负债，流动和非流动 23.2美元clf_MineReclamationAndClosingLiabilityCurrentAndNoncurrent
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= clf_PreviouslyOwnedOrOperatingFacilitiesMember
/ clf_MineClosureAxis
= clf_LTVSteelMiningCompanyMember 		22.9美元clf_MineReclamationAndClosingLiabilityCurrentAndNoncurrent
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= clf_PreviouslyOwnedOrOperatingFacilitiesMember
/ clf_MineClosureAxis
= clf_LTVSteelMiningCompanyMember