DEBT AND CREDIT FACILITIES (Schedule Of Long-Term Debt) (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, 2013
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Dec. 31, 2014
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Mar. 30, 2015
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Debt Instrument [Line Items] |
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Gain on extinguishment of debt |
$ 313,700,000us-gaap_GainsLossesOnExtinguishmentOfDebt
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$ 0us-gaap_GainsLossesOnExtinguishmentOfDebt
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Total Face Amount |
3,621,500,000us-gaap_DebtInstrumentFaceAmount
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3,980,000,000us-gaap_DebtInstrumentFaceAmount
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Letters of credit outstanding |
136,200,000us-gaap_LettersOfCreditOutstandingAmount
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149,500,000us-gaap_LettersOfCreditOutstandingAmount
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Long-term Debt |
2,880,900,000us-gaap_LongTermDebt
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2,843,300,000us-gaap_LongTermDebt
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Current portion of long-term debt |
0us-gaap_LongTermDebtCurrent
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0us-gaap_LongTermDebtCurrent
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Long-term debt noncurrent portion |
2,880,900,000us-gaap_LongTermDebtNoncurrent
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2,843,300,000us-gaap_LongTermDebtNoncurrent
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$700 Million 4.875% 2021 Senior Note [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Repurchased Face Amount |
58,300,000us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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Stated interest rate |
4.875%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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4.875%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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Debt Repurchase Discount |
52.00%clf_DebtRepurchaseDiscount / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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Debt Instrument, Face Amount Exchanged |
208,500,000clf_DebtInstrumentFaceAmountExchanged / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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Type |
Fixed
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Fixed
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Final Maturity |
2021
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2021
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Total Face Amount |
700,000,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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700,000,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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Debt Instrument, Par Value |
423,200,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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690,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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Long-term Debt |
422,900,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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[1] |
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689,500,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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[1] |
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Debt Instrument, Unamortized Discount |
300,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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500,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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Imputed interest rate |
4.89%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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4.88%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember
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$500 million 4.80% 2020 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Repurchased Face Amount |
43,800,000us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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Stated interest rate |
4.80%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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4.80%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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Debt Repurchase Discount |
54.30%clf_DebtRepurchaseDiscount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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Debt Instrument, Face Amount Exchanged |
137,800,000clf_DebtInstrumentFaceAmountExchanged / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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Type |
Fixed
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Fixed
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Final Maturity |
2020
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2020
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Total Face Amount |
500,000,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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500,000,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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Debt Instrument, Par Value |
308,500,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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490,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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Long-term Debt |
308,100,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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489,400,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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Debt Instrument, Unamortized Discount |
400,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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600,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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Imputed interest rate |
4.83%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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4.83%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember
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$800 Million 6.25% 2040 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Repurchased Face Amount |
45,900,000us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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Stated interest rate |
6.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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Debt Repurchase Discount |
52.50%clf_DebtRepurchaseDiscount / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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Debt Instrument, Face Amount Exchanged |
261,300,000clf_DebtInstrumentFaceAmountExchanged / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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Type |
Fixed
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Fixed
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Final Maturity |
2040
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2040
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Total Face Amount |
800,000,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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Debt Instrument, Par Value |
492,800,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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800,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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Long-term Debt |
487,000,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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790,500,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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[3] |
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Debt Instrument, Unamortized Discount |
5,800,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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9,500,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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Imputed interest rate |
6.34%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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6.34%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember
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$400 Million 5.90% 2020 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Repurchased Face Amount |
1,300,000us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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Stated interest rate |
5.90%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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5.90%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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Debt Repurchase Discount |
58.00%clf_DebtRepurchaseDiscount / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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Debt Instrument, Face Amount Exchanged |
67,000,000clf_DebtInstrumentFaceAmountExchanged / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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Type |
Fixed
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Fixed
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Final Maturity |
2020
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2020
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Total Face Amount |
400,000,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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400,000,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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Debt Instrument, Par Value |
326,800,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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395,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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Long-term Debt |
325,700,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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[4] |
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393,700,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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[4] |
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Debt Instrument, Unamortized Discount |
1,100,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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1,300,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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Imputed interest rate |
5.98%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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5.98%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember
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$500 Million 3.95% 2018 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Repurchased Face Amount |
44,000,000us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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Stated interest rate |
3.95%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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3.95%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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Debt Repurchase Discount |
77.50%clf_DebtRepurchaseDiscount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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Type |
Fixed
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Fixed
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Final Maturity |
2018
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2018
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Total Face Amount |
500,000,000.0us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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500,000,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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Debt Instrument, Par Value |
436,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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480,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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Long-term Debt |
433,800,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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[5] |
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477,400,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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[5] |
Ìý
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Debt Instrument, Unamortized Discount |
2,200,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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2,600,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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Imputed interest rate |
6.32%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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Ìý
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5.17%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember
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Five hundred forty million Eight point two five Twenty twenty First Lien Notes [Member] |
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Debt Instrument [Line Items] |
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Stated interest rate |
8.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_FivehundredfortymillionEightpointtwofiveTwentytwentyFirstLienNotesMember
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Type |
Fixed
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Final Maturity |
2020
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Total Face Amount |
540,000,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FivehundredfortymillionEightpointtwofiveTwentytwentyFirstLienNotesMember
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0us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FivehundredfortymillionEightpointtwofiveTwentytwentyFirstLienNotesMember
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Ìý
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Debt Instrument, Par Value |
540,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_FivehundredfortymillionEightpointtwofiveTwentytwentyFirstLienNotesMember
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Long-term Debt |
503,500,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_FivehundredfortymillionEightpointtwofiveTwentytwentyFirstLienNotesMember
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[5] |
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Debt Instrument, Unamortized Discount |
36,500,000.0us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_FivehundredfortymillionEightpointtwofiveTwentytwentyFirstLienNotesMember
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Imputed interest rate |
9.97%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_FivehundredfortymillionEightpointtwofiveTwentytwentyFirstLienNotesMember
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Five hundred Forty-four Million Seven Point Seven Five Twenty Twenty Second Lien Notes [Member] |
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Debt Instrument [Line Items] |
Ìý
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Stated interest rate |
7.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Discount Received in Debt Exchange of $400M 5.90% Notes |
15,500,000clf_DiscountReceivedinDebtExchangeof400M5.90Notes / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Debt Instrument, Face Amount Received in Debt Exchange of $400M 5.90% Notes |
57,500,000clf_DebtInstrumentFaceAmountReceivedinDebtExchangeof400M5.90Notes / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Debt Instrument, Face Amount Received in Debt Exchange of $800M 6.25% Notes |
203,500,000clf_DebtInstrumentFaceAmountReceivedinDebtExchangeof800M6.25Notes / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Discount Received in Debt Exchange of $800M 6.25% Notes |
55,000,000clf_DiscountReceivedinDebtExchangeof800M6.25Notes / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Discount Received in Debt Exchange of $500M 4.80% Notes |
30,500,000clf_DiscountReceivedinDebtExchangeof500M4.80Notes / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Debt Instrument, Face Amount Received in Debt Exchange of $500M 4.80% Notes |
112,900,000clf_DebtInstrumentFaceAmountReceivedinDebtExchangeof500M4.80Notes / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Discount Received in Debt Exchange of $700M 4.875% Notes |
46,000,000clf_DiscountReceivedinDebtExchangeof700M4.875Notes / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Debt instrument, Face Amount Received in Debt Exchange of $700M 4.875% Notes |
170,300,000clf_DebtinstrumentFaceAmountReceivedinDebtExchangeof700M4.875Notes / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Type |
Fixed
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Final Maturity |
2020
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Total Face Amount |
544,200,000us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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0us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Debt Instrument, Par Value |
544,200,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Long-term Debt |
397,200,000us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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[5] |
Ìý
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Ìý
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Ìý
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Ìý
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Debt Instrument, Unamortized Discount |
147,000,000us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Ìý
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Ìý
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Imputed interest rate |
15.55%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Ìý
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15.55%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = clf_FivehundredFortyfourMillionSevenPointSevenFiveTwentyTwentySecondLienNotesMember
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Ìý
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Revolving Credit Facility [Member] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Debt Instrument [Line Items] |
Ìý
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Ìý
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Ìý
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Ìý
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Type |
Variable
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Ìý
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Variable
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Ìý
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Ìý
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Final Maturity |
2020
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Ìý
|
2017
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Ìý
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Ìý
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Debt Instrument, Par Value |
550,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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Ìý
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Ìý
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1,125,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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|
900,000,000clf_DebtInstrumentParValue / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
|
Credit facility, amount outstanding |
0us-gaap_LineOfCredit / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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[6] |
Ìý
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Ìý
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0us-gaap_LineOfCredit / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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[7] |
Ìý
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Revolving credit facility, borrowing capacity |
441,100,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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Ìý
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Ìý
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Ìý
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Letters of credit outstanding |
136,200,000us-gaap_LettersOfCreditOutstandingAmount / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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Ìý
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149,500,000us-gaap_LettersOfCreditOutstandingAmount / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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Ìý
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Foreign Exchange Hedge Obligations |
5,500,000clf_ForeignExchangeHedgeObligations / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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Ìý
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Ìý
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Ìý
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Ìý
|
Imputed interest rate |
0.00%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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Ìý
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Ìý
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2.94%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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Credit facility remaining capacity |
299,400,000us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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Ìý
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Ìý
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975,500,000us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember
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Ìý
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Interest Rate Swap [Member] |
Ìý
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Ìý
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Ìý
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Ìý
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Debt Instrument [Line Items] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Fair Value Adjustment to Interest Rate Hedge |
2,700,000clf_FairValueAdjustmenttoInterestRateHedge / us-gaap_DebtInstrumentAxis = us-gaap_InterestRateSwapMember
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Ìý
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Ìý
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2,800,000clf_FairValueAdjustmenttoInterestRateHedge / us-gaap_DebtInstrumentAxis = us-gaap_InterestRateSwapMember
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Ìý
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Debt Repurchase [Member] | $700 Million 4.875% 2021 Senior Note [Member] |
Ìý
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Ìý
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Ìý
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Ìý
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Debt Instrument [Line Items] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
|
Gain on extinguishment of debt |
20,000,000us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember / us-gaap_ExtinguishmentOfDebtAxis = clf_DebtRepurchaseMember
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Ìý
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Ìý
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Ìý
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Debt Repurchase [Member] | $500 million 4.80% 2020 Senior Notes [Member] |
Ìý
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Ìý
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Debt Instrument [Line Items] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Gain on extinguishment of debt |
15,600,000us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember / us-gaap_ExtinguishmentOfDebtAxis = clf_DebtRepurchaseMember
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Ìý
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Ìý
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Ìý
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|
Debt Repurchase [Member] | $800 Million 6.25% 2040 Senior Notes [Member] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Debt Instrument [Line Items] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
|
Gain on extinguishment of debt |
15,000,000us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember / us-gaap_ExtinguishmentOfDebtAxis = clf_DebtRepurchaseMember
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Ìý
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Ìý
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Ìý
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Ìý
|
Debt Repurchase [Member] | $400 Million 5.90% 2020 Senior Notes [Member] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
|
Debt Instrument [Line Items] |
Ìý
|
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Ìý
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Ìý
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Ìý
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Ìý
|
Gain on extinguishment of debt |
300,000us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember / us-gaap_ExtinguishmentOfDebtAxis = clf_DebtRepurchaseMember
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Ìý
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Ìý
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Ìý
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Ìý
|
Debt Repurchase [Member] | $500 Million 3.95% 2018 Senior Notes [Member] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Debt Instrument [Line Items] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
|
Gain on extinguishment of debt |
7,100,000us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionThreePointNineFiveTwoThousandEighteenSeniorNoteMember / us-gaap_ExtinguishmentOfDebtAxis = clf_DebtRepurchaseMember
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Ìý
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Ìý
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Ìý
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Ìý
|
Exchange of Debt [Member] | $700 Million 4.875% 2021 Senior Note [Member] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
|
Debt Instrument [Line Items] |
Ìý
|
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Ìý
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Ìý
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Ìý
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Ìý
|
Gain on extinguishment of debt |
83,100,000us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = clf_SevenHundredMillionFourPointEightSevenFiveTwoThousandTwentyoneSeniorNoteMember / us-gaap_ExtinguishmentOfDebtAxis = clf_ExchangeofDebtMember
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Ìý
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Ìý
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Ìý
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Ìý
|
Exchange of Debt [Member] | $500 million 4.80% 2020 Senior Notes [Member] |
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
|
Debt Instrument [Line Items] |
Ìý
|
|
Ìý
|
Ìý
|
Ìý
|
|
Ìý
|
Gain on extinguishment of debt |
54,600,000us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = clf_FiveHundredMillionFourPointEightZeroPercentSeniorNoteMember / us-gaap_ExtinguishmentOfDebtAxis = clf_ExchangeofDebtMember
|
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Ìý
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Ìý
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Ìý
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Ìý
|
Exchange of Debt [Member] | $800 Million 6.25% 2040 Senior Notes [Member] |
Ìý
|
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Ìý
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Ìý
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Ìý
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Ìý
|
Debt Instrument [Line Items] |
Ìý
|
|
Ìý
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Ìý
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Ìý
|
|
Ìý
|
Gain on extinguishment of debt |
107,300,000us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = clf_EightHundredMillionSixPointTwoFivePercentSeniorNotesDueTwoThousandFortyMember / us-gaap_ExtinguishmentOfDebtAxis = clf_ExchangeofDebtMember
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Ìý
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Ìý
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Ìý
|
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Ìý
|
Exchange of Debt [Member] | $400 Million 5.90% 2020 Senior Notes [Member] |
Ìý
|
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Ìý
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Ìý
|
Ìý
|
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Ìý
|
Debt Instrument [Line Items] |
Ìý
|
|
Ìý
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Ìý
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Ìý
|
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Ìý
|
Gain on extinguishment of debt |
$ 24,500,000us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = clf_FourHundredMillionFivePointNineZeroTwoThousandAndTwentySeniorNoteMember / us-gaap_ExtinguishmentOfDebtAxis = clf_ExchangeofDebtMember
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Ìý
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Ìý
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Ìý
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