根据第13和15(d)条提交的年度报告

退休金及其他退休后福利（退休金计划资产的公允价值）（详情）

v2.4.1.9
养老金及其他退休后福利（养老金计划资产公允价值）（详情）（美元）
除非另有说明，单位为百万
12个月结束
2014年12月31日
2014年9月30日
2013年12月31日
2012年12月31日
设定受益计划及其他退休后福利计划表        
投资承诺准备金 55.5美元clf_ReserveForInvestmentCommitments 45.0美元clf_ReserveForInvestmentCommitments    
计划资产的公允价值 205.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets   188.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets 200.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
退休金福利〔成员〕        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 949.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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股票证券[成员]b|皇冠体育官网大盘股[成员]|养老金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 248.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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股权证券[会员]|美股中小股[会员]|养老金福利[会员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 55.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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股权证券【会员】|国际【会员】|养老金福利【会员】        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 157.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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固定收益投资[成员]b|退休金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 275.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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对冲基金〔成员〕        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 59.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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对冲基金[成员]b|养老金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 59.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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私募股权基金〔成员〕        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 31.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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私募股权基金[成员]b|养老金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 31.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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结构性融资〔委员〕        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 65.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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赎回要求通知期 90天      
结构性金融[成员]b|养老金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 65.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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房地产〔成员〕        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 50.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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赎回要求通知期 45天      
房地产[成员]b|养老金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 50.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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现金[成员]|退休金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 6.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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相同资产/负债在活跃市场的报价（第一级）[成员]|退休金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 712.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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相同资产/负债活跃市场报价（第一级）[成员]|股票证券[成员]|皇冠体育官网大盘股[成员]|退休金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 248.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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相同资产/负债活跃市场报价（一级）[成员]|股权证券[成员]|美股中小盘股[成员]|养老金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 55.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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相同资产/负债活跃市场报价（一级）[会员]|股权证券[会员]|国际[会员]|养老金福利[会员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 157.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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相同资产/负债活跃市场报价（第一级）[成员]|固定收益投资[成员]|退休金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 243.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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相同资产/负债活跃市场报价（第一级）[成员]|对冲基金[成员]|退休金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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相同资产/负债活跃市场报价（第一级）[成员]|私募股权基金[成员]|退休金福利[成员]        
设定受益计划及其他退休后福利计划表        
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相同资产/负债活跃市场报价（第一级）[成员]|结构性金融[成员]|退休金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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相同资产/负债活跃市场报价（第一级）[成员]|房地产[成员]|退休金福利[成员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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相同资产/负债活跃市场报价（一级）[会员]|现金[会员]|养老金福利[会员]        
设定受益计划及其他退休后福利计划表        
计划资产的公允价值 6.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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公允价值，投入，第2级[成员]|养老金福利[成员]        
设定受益计划及其他退休后福利计划表        
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