$CLF
CLEVELAND-CLIFFS INC. Stock $clf

$clf Overview Financials Valuation SEC Filings Company Website

2019 Q2 Form 10-Q Financial Statement

#000076406519000134 Filed on July 19, 2019

Income Statement

Concept	2019 Q2	2018 Q4	2018 Q2
Revenue	$743.2M	$696.3M	$714.3M
YoY Change	4.05%	36.05%	51.56%
Cost Of Revenue	$480.2M	$493.3M	$429.8M
YoY Change	11.73%	25.46%	31.6%
Gross Profit	$263.0M	$202.0M	$284.5M
YoY Change	-7.56%	73.99%	96.61%
Gross Profit Margin	35.39%	29.01%	39.83%
Selling, General & Admin	$29.40M	$35.40M	$26.20M
YoY Change	12.21%	29.2%	-1.5%
% of Gross Profit	11.18%	17.52%	9.21%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$20.90M	$20.40M	$25.50M
YoY Change	-18.04%	-4.67%	18.06%
% of Gross Profit	7.95%	10.1%	8.96%
Operating Expenses	$36.20M	$39.60M	$30.30M
YoY Change	19.47%	382.93%	2.71%
Operating Profit	$226.8M	$162.4M	$254.2M
YoY Change	-10.78%	50.51%	120.66%
Interest Expense	-$26.10M	-$26.00M	-$31.30M
YoY Change	-16.61%	3.17%	5.74%
% of Operating Profit	-11.51%	-16.01%	-12.31%
Other Income/Expense, Net	-$43.40M	$4.100M	-$26.60M
YoY Change	63.16%	57.69%	-18.15%
Pretax Income	$183.4M	$134.5M	$227.6M
YoY Change	-19.42%	53.19%	175.21%
Income Tax	$22.00M	-$489.6M	-$1.800M
% Of Pretax Income	12.0%	-364.01%	-0.79%
Net Earnings	$160.8M	$609.5M	$165.1M
YoY Change	-2.6%	96.68%	419.18%
Net Earnings / Revenue	21.64%	87.53%	23.11%
Basic Earnings Per Share	$0.59	$2.06	$0.55
Diluted Earnings Per Share	$0.57	$1.98	$0.55
COMMON SHARES
Basic Shares Outstanding	275.8M shares	298.0M shares	297.6M shares
Diluted Shares Outstanding	285.5M shares		301.3M shares

Balance Sheet

Concept	2019 Q2	2018 Q4	2018 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$377.0M	$823.0M	$803.0M
YoY Change	-53.05%	-15.85%	149.38%
Cash & Equivalents	$377.2M	$823.2M	$802.5M
Short-Term Investments
Other Short-Term Assets	$42.30M	$39.80M	$26.80M
YoY Change	57.84%	258.56%	-69.82%
Inventory	$219.0M	$181.1M	$256.4M
Prepaid Expenses
Receivables	$193.1M	$226.7M	$152.6M
Other Receivables	$59.00M	$117.0M	$0.00
Total Short-Term Assets	$1.119B	$1.480B	$1.547B
YoY Change	-27.64%	-4.21%	70.31%
LONG-TERM ASSETS
Property, Plant & Equipment	$1.597B	$1.286B	$1.081B
YoY Change	47.72%	24.4%	8.23%
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$118.3M	$177.9M	$117.7M
YoY Change	0.51%	75.1%	-4.07%
Total Long-Term Assets	$2.274B	$2.050B	$1.505B
YoY Change	51.12%	45.51%	34.12%
TOTAL ASSETS
Total Short-Term Assets	$1.119B	$1.480B	$1.547B
Total Long-Term Assets	$2.274B	$2.050B	$1.505B
Total Assets	$3.393B	$3.530B	$3.052B
YoY Change	11.2%	19.51%	50.31%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$188.1M	$186.8M	$119.0M
YoY Change	58.07%	87.74%	6.54%
Accrued Expenses	$90.00M	$158.9M	$85.10M
YoY Change	5.76%	100.88%	-24.56%
Deferred Revenue	$15.50M	$21.00M
YoY Change		-11.76%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$437.4M	$468.2M	$474.9M
YoY Change	-7.9%	3.54%	14.9%
LONG-TERM LIABILITIES
Long-Term Debt	$2.105B	$2.093B	$2.297B
YoY Change	-8.38%	-9.17%	42.51%
Other Long-Term Liabilities	$149.7M	$123.6M	$158.3M
YoY Change	-5.43%	-24.4%	-18.28%
Total Long-Term Liabilities	$2.254B	$2.217B	$2.455B
YoY Change	-8.19%	-10.18%	35.99%
TOTAL LIABILITIES
Total Short-Term Liabilities	$437.4M	$468.2M	$474.9M
Total Long-Term Liabilities	$2.254B	$2.217B	$2.455B
Total Liabilities	$3.108B	$3.105B	$3.358B
YoY Change	-7.45%	-8.6%	24.51%
SHAREHOLDERS EQUITY
Retained Earnings	-$2.953B	-$3.060B	-$4.093B
YoY Change	-27.85%	-27.26%	-10.46%
Common Stock
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)	$391.3M	$186.1M	$147.5M
YoY Change	165.29%	9.73%	-37.63%
Treasury Stock Shares	3.879M shares	9.275M shares	4.040M shares
Shareholders Equity	$285.6M	$424.2M	-$306.3M
YoY Change
Total Liabilities & Shareholders Equity	$3.393B	$3.530B	$3.052B
YoY Change	11.2%	19.51%	50.31%

Cashflow Statement

Concept	2019 Q2	2018 Q4	2018 Q2
OPERATING ACTIVITIES
Net Income	$160.8M	$609.5M	$165.1M
YoY Change	-2.6%	96.68%	419.18%
Depreciation, Depletion And Amortization	$20.90M	$20.40M	$25.50M
YoY Change	-18.04%	-4.67%	18.06%
Cash From Operating Activities	$263.9M	$293.0M	$93.60M
YoY Change	181.94%	115.92%	78.63%
INVESTING ACTIVITIES
Capital Expenditures	-$161.7M	-$97.20M	-$29.70M
YoY Change	444.44%	34.63%	81.1%
Acquisitions
YoY Change
Other Investing Activities	-$5.100M	-$2.200M	$1.300M
YoY Change	-492.31%	-466.67%	-128.89%
Cash From Investing Activities	-$166.8M	-$99.40M	-$28.40M
YoY Change	487.32%	38.83%	35.89%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-150.1M	-267.5M	-18.70M
YoY Change	702.67%	-138.91%	-60.04%
NET CHANGE
Cash From Operating Activities	263.9M	293.0M	93.60M
Cash From Investing Activities	-166.8M	-99.40M	-28.40M
Cash From Financing Activities	-150.1M	-267.5M	-18.70M
Net Change In Cash	-53.00M	-73.90M	46.50M
YoY Change	-213.98%	-109.83%	-403.92%
FREE CASH FLOW
Cash From Operating Activities	$263.9M	$293.0M	$93.60M
Capital Expenditures	-$161.7M	-$97.20M	-$29.70M
Free Cash Flow	$425.6M	$390.2M	$123.3M
YoY Change	245.17%	87.69%	79.22%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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	dei	Amendment Flag AmendmentFlag	false
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q2
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
	dei	Entity Central Index Key EntityCentralIndexKey	0000764065
CY2018Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.125
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CY2019Q2	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	301886794	shares
CY2018Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	292611569	shares
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CY2018Q2	us-gaap	Extinguishment Of Debt Amount ExtinguishmentOfDebtAmount	15500000	USD
CY2019Q2	us-gaap	Preferred Stock No Par Value PreferredStockNoParValue	0
CY2018Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	9275225	shares
CY2019Q2	us-gaap	Treasury Stock Shares TreasuryStockShares	3879341	shares
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2019-06-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	1-8944
	dei	Entity Registrant Name EntityRegistrantName	CLEVELAND-CLIFFS INC.
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	OH
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	34-1464672
	dei	Entity Address Address Line1 EntityAddressAddressLine1	200 Public Square,
	dei	Entity Address City Or Town EntityAddressCityOrTown	Cleveland,
	dei	Entity Address State Or Province EntityAddressStateOrProvince	OH
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	44114-2315
	dei	City Area Code CityAreaCode	216
	dei	Local Phone Number LocalPhoneNumber	694-5700
	dei	Security12b Title Security12bTitle	Common shares, par value $0.125 per share
	dei	Trading Symbol TradingSymbol	CLF
	dei	Security Exchange Name SecurityExchangeName	NYSE
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Shell Company EntityShellCompany	false
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	us-gaap	Net Income Loss NetIncomeLoss	80800000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.59
CY2018Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.77
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.49
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.73
CY2019Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0
CY2018Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.22
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.46
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.59
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.55
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.49
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.27
CY2019Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.57
CY2018Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.76
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.47
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.72
CY2019Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0
CY2018Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.21
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.45
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.57
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.55
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.47
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.27
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	275769000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	297618000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	282647000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	297442000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	285479000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	301275000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	293580000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	301143000	shares
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	160800000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	165100000	USD
	us-gaap	Net Income Loss NetIncomeLoss	138700000	USD
	us-gaap	Net Income Loss NetIncomeLoss	80800000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-5800000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-6700000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-11500000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-13400000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	0	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	2200000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	0	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	2900000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-2100000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	200000	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	600000	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	500000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3700000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	9100000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	12100000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	16800000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	164500000	USD
CY2018Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	174200000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	150800000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	97600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	138700000	USD
	us-gaap	Net Income Loss NetIncomeLoss	80800000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	40900000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	49400000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-18200000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	200000	USD
	us-gaap	Unrealized Gain Loss On Derivatives And Commodity Contracts UnrealizedGainLossOnDerivativesAndCommodityContracts	27200000	USD
	us-gaap	Unrealized Gain Loss On Derivatives And Commodity Contracts UnrealizedGainLossOnDerivativesAndCommodityContracts	123500000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-46600000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-12600000	USD
	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	-127800000	USD
	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	-61800000	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	131100000	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	125600000	USD
	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-62800000	USD
	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-4600000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	151100000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-49300000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	294400000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	42100000	USD
	clf	Paymentsfor Deposits On Property Plantand Equipment PaymentsforDepositsOnPropertyPlantandEquipment	6500000	USD
	clf	Paymentsfor Deposits On Property Plantand Equipment PaymentsforDepositsOnPropertyPlantandEquipment	72300000	USD
	us-gaap	Proceeds From Sale Of Other Assets Investing Activities ProceedsFromSaleOfOtherAssetsInvestingActivities	0	USD
	us-gaap	Proceeds From Sale Of Other Assets Investing Activities ProceedsFromSaleOfOtherAssetsInvestingActivities	14600000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-8500000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	0	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-292400000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-99800000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	252900000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	28900000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	0	USD
	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	720900000	USD
	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	0	USD
	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	6800000	USD
	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	1500000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	729300000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	15300000	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-10900000	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-8900000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-307900000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-25700000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	0	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-1000000.0	USD
	clf	Increase Decreasein Cashand Cash Equivalents Including Cash Classified Within Other Current Assets Relatedto Discontinued Operations IncreaseDecreaseinCashandCashEquivalentsIncludingCashClassifiedWithinOtherCurrentAssetsRelatedtoDiscontinuedOperations	-449200000	USD
	clf	Increase Decreasein Cashand Cash Equivalents Including Cash Classified Within Other Current Assets Relatedto Discontinued Operations IncreaseDecreaseinCashandCashEquivalentsIncludingCashClassifiedWithinOtherCurrentAssetsRelatedtoDiscontinuedOperations	-175800000	USD
	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	3200000	USD
	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	0	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-446000000.0	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-175800000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	823200000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	978300000	USD
CY2019Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	377200000	USD
CY2018Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	802500000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	424200000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	-22100000	USD
CY2019Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	8400000	USD
CY2019Q1	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-13700000	USD
CY2019Q1	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-10000000.0	USD
CY2019Q1	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	124300000	USD
CY2019Q1	us-gaap	Dividends Common Stock DividendsCommonStock	14500000	USD
CY2019Q1	us-gaap	Stockholders Equity StockholdersEquity	261700000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	160800000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3700000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	164500000	USD
CY2019Q2	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	4600000	USD
CY2019Q2	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	128600000	USD
CY2019Q2	us-gaap	Dividends Common Stock DividendsCommonStock	16600000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	285600000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-444100000	USD
CY2018Q1	us-gaap	New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Quantification NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification	34000000.0	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	-84300000	USD
CY2018Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	7700000	USD
CY2018Q1	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-76600000	USD
CY2018Q1	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	1900000	USD
CY2018Q1	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-484800000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	165100000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	9100000	USD
CY2018Q2	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	174200000	USD
CY2018Q2	clf	Undistributed Earnings Losses Related To Noncontrolling Interests UndistributedEarningsLossesRelatedToNoncontrollingInterests	-200000	USD
CY2018Q2	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	4500000	USD
CY2018Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-306300000	USD
	us-gaap	Number Of Reporting Units NumberOfReportingUnits	2	unit
	us-gaap	Number Of Reporting Units NumberOfReportingUnits	2	unit
CY2019Q2	us-gaap	Revenues Revenues	743200000	USD
	us-gaap	Revenues Revenues	900200000	USD
CY2019Q2	us-gaap	Gross Profit GrossProfit	263000000.0	USD
	us-gaap	Gross Profit GrossProfit	293900000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	160800000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	165100000	USD
	us-gaap	Net Income Loss NetIncomeLoss	138700000	USD
	us-gaap	Net Income Loss NetIncomeLoss	80800000	USD
CY2019Q2	clf	Ebitda EBITDA	230100000	USD
CY2018Q2	clf	Ebitda EBITDA	221100000	USD
	clf	Ebitda EBITDA	249300000	USD
	clf	Ebitda EBITDA	209900000	USD
CY2019Q2	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-100000	USD
CY2018Q2	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-100000	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	0	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-500000	USD
CY2019Q2	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-17900000	USD
CY2018Q2	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	200000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-18200000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	200000	USD
CY2019Q2	us-gaap	Severance Costs1 SeveranceCosts1	0	USD
CY2018Q2	us-gaap	Severance Costs1 SeveranceCosts1	0	USD
	us-gaap	Severance Costs1 SeveranceCosts1	-1700000	USD
	us-gaap	Severance Costs1 SeveranceCosts1	0	USD
CY2019Q2	clf	Adjusted Ebitda AdjustedEBITDA	248500000	USD
CY2018Q2	clf	Adjusted Ebitda AdjustedEBITDA	275700000	USD
	clf	Adjusted Ebitda AdjustedEBITDA	269600000	USD
	clf	Adjusted Ebitda AdjustedEBITDA	328000000.0	USD
CY2019Q2	clf	Ebitda EBITDA	230100000	USD
CY2018Q2	clf	Ebitda EBITDA	221100000	USD
	clf	Ebitda EBITDA	249300000	USD
	clf	Ebitda EBITDA	209900000	USD
CY2019Q2	clf	Adjusted Ebitda AdjustedEBITDA	248500000	USD
CY2018Q2	clf	Adjusted Ebitda AdjustedEBITDA	275700000	USD
	clf	Adjusted Ebitda AdjustedEBITDA	269600000	USD
	clf	Adjusted Ebitda AdjustedEBITDA	328000000.0	USD
CY2019Q2	clf	Depreciation Depletionand Amortizationexcluding Depreciation Amortizationand Depletionexpensefor Discontinued Operations DepreciationDepletionandAmortizationexcludingDepreciationAmortizationandDepletionexpenseforDiscontinuedOperations	21000000.0	USD
CY2018Q2	clf	Depreciation Depletionand Amortizationexcluding Depreciation Amortizationand Depletionexpensefor Discontinued Operations DepreciationDepletionandAmortizationexcludingDepreciationAmortizationandDepletionexpenseforDiscontinuedOperations	17000000.0	USD
	clf	Depreciation Depletionand Amortizationexcluding Depreciation Amortizationand Depletionexpensefor Discontinued Operations DepreciationDepletionandAmortizationexcludingDepreciationAmortizationandDepletionexpenseforDiscontinuedOperations	40900000	USD
	clf	Depreciation Depletionand Amortizationexcluding Depreciation Amortizationand Depletionexpensefor Discontinued Operations DepreciationDepletionandAmortizationexcludingDepreciationAmortizationandDepletionexpenseforDiscontinuedOperations	34200000	USD
CY2019Q2	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	191600000	USD
CY2018Q2	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	70400000	USD
	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	320900000	USD
	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	149300000	USD
CY2019Q2	us-gaap	Assets Assets	3393200000	USD
CY2018Q4	us-gaap	Assets Assets	3529600000	USD
CY2018Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	21000000.0	USD
CY2017Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	23800000	USD
CY2019Q2	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	15500000	USD
CY2018Q1	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	20000000.0	USD
	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	47100000	USD
CY2018	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	51300000	USD
CY2019Q2	us-gaap	Inventory Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	186200000	USD
CY2019Q2	us-gaap	Inventory Work In Process Net Of Reserves InventoryWorkInProcessNetOfReserves	32800000	USD
CY2019Q2	us-gaap	Inventory Net InventoryNet	219000000.0	USD
CY2018Q4	us-gaap	Inventory Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	77800000	USD
CY2018Q4	us-gaap	Inventory Work In Process Net Of Reserves InventoryWorkInProcessNetOfReserves	10100000	USD
CY2018Q4	us-gaap	Inventory Net InventoryNet	87900000	USD
CY2019Q2	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	2658000000.0	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	2308400000	USD
CY2019Q2	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1060700000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1022400000	USD
CY2019Q2	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1597300000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1286000000.0	USD
CY2019Q2	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	5900000	USD
	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	9900000	USD
CY2018Q2	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	1100000	USD
	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	2100000	USD
CY2019Q2	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2104500000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2092900000	USD
CY2019Q2	us-gaap	Extinguishment Of Debt Amount ExtinguishmentOfDebtAmount	714000000.0	USD
CY2019Q2	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-17900000	USD
	us-gaap	Extinguishment Of Debt Amount ExtinguishmentOfDebtAmount	724000000.0	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-18200000	USD
	us-gaap	Extinguishment Of Debt Amount ExtinguishmentOfDebtAmount	15500000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	200000	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal Remainder Of Fiscal Year LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear	0	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	0	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	0	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	0	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	0	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	400000000.0	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1838000000.0	USD
CY2019Q2	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	2238000000.0	USD
CY2019Q2	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	302300000	USD
CY2019Q2	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	118300000	USD
CY2019Q2	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	420600000	USD
CY2019Q2	us-gaap	Derivative Liabilities DerivativeLiabilities	2600000	USD
CY2019Q2	us-gaap	Financial Liabilities Fair Value Disclosure FinancialLiabilitiesFairValueDisclosure	2600000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	543400000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	91500000	USD
CY2018Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	634900000	USD
CY2018Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	3700000	USD
CY2018Q4	us-gaap	Financial Liabilities Fair Value Disclosure FinancialLiabilitiesFairValueDisclosure	3700000	USD
CY2019Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	106700000	USD
CY2018Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	93500000	USD
CY2018Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	91400000	USD
CY2017Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	49500000	USD
CY2019Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-74300000	USD
CY2018Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-158600000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-89600000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-202800000	USD
CY2019Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	62900000	USD
CY2018Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	77500000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	62900000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	77700000	USD
CY2019Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	118100000	USD
CY2018Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	174600000	USD
CY2019Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	118100000	USD
CY2018Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	174600000	USD
CY2019Q2	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	73000000.0	USD
CY2018Q2	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	80600000	USD
	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	88300000	USD
	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	125100000	USD
CY2019Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	9800000	USD
CY2018Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	0	USD
CY2018Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	0	USD
CY2017Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	1700000	USD
CY2019Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	4500000	USD
CY2018Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	-3700000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	-5300000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	-4300000	USD
CY2019Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	5300000	USD
CY2018Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	700000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	5300000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	3000000.0	USD
CY2019Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	0	USD
CY2018Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	3000000.0	USD
CY2019Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	0	USD
CY2018Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	3000000.0	USD
CY2019Q2	us-gaap	Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	0	USD
CY2018Q2	us-gaap	Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-3000000.0	USD
	us-gaap	Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	0	USD
	us-gaap	Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-3000000.0	USD
CY2019Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	11.24
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P2Y10M13D
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.675
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0255
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	18.31
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Discount From Market Price Offering Date ShareBasedCompensationArrangementByShareBasedPaymentAwardDiscountFromMarketPriceOfferingDate	1.6290
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.121
	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.001
CY2019Q2	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-400000	USD
	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-800000	USD
CY2018Q2	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-2000000.0	USD
	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-13700000	USD
CY2018Q2	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-2000000.0	USD
	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-13700000	USD
	clf	Repealof Am Tamount RepealofAMTamount	14500000	USD
CY2019Q2	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	2400000	USD
CY2018Q4	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	2500000	USD
CY2019Q2	clf	Mine Reclamation And Closing Liability Current And Noncurrent MineReclamationAndClosingLiabilityCurrentAndNoncurrent	179500000	USD
CY2018Q4	clf	Mine Reclamation And Closing Liability Current And Noncurrent MineReclamationAndClosingLiabilityCurrentAndNoncurrent	174900000	USD
CY2019Q2	us-gaap	Accrued Reclamation Costs Current AccruedReclamationCostsCurrent	2800000	USD
CY2018Q4	us-gaap	Accrued Reclamation Costs Current AccruedReclamationCostsCurrent	2900000	USD
CY2019Q2	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	176700000	USD
CY2018Q4	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	172000000.0	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	172400000	USD
CY2017Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	168400000	USD
	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	5100000	USD
CY2018	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	9500000	USD
	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	400000	USD
CY2018	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	1000000.0	USD
	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	0	USD
CY2018	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	-4500000	USD
CY2019Q2	us-gaap	Asset Retirement Obligation AssetRetirementObligation	177100000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	172400000	USD
CY2019Q2	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	118300000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	91500000	USD
CY2019Q2	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	2600000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	3700000	USD
CY2019Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-600000	USD
CY2018Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-64300000	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-600000	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-135200000	USD
	us-gaap	Noncash Investing And Financing Activities Related Text NoncashInvestingAndFinancingActivitiesRelatedText	For the six months ended June 30, 2018, we had $28.6 million of non-cash financing activities related to the settlement of capital lease obligations at Asia Pacific Iron Ore.
CY2018Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	200000000	USD
CY2019Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	100000000	USD
CY2019Q2	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	12900000	shares
	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	24400000	shares
CY2019Q2	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	128600000	USD
	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	252900000	USD
CY2019Q2	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	200000	USD
CY2019Q2	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	17100000	USD
	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	320900000	USD
	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	149300000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	-3600000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	-34900000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	24800000	USD
	us-gaap	Capital Lease Obligations Incurred CapitalLeaseObligationsIncurred	0	USD
	clf	Governmentgrantrebate Governmentgrantrebate	-8400000	USD
	clf	Governmentgrantrebate Governmentgrantrebate	0	USD
	clf	Payments To Acquire Property Plant And Equipment Net PaymentsToAcquirePropertyPlantAndEquipmentNet	-300900000	USD
	clf	Payments To Acquire Property Plant And Equipment Net PaymentsToAcquirePropertyPlantAndEquipmentNet	-114400000	USD
CY2019Q2	us-gaap	Dividends Payable Current DividendsPayableCurrent	16200000	USD
CY2019Q2	us-gaap	Revenue From Related Parties RevenueFromRelatedParties	415800000	USD
CY2018Q2	us-gaap	Revenue From Related Parties RevenueFromRelatedParties	409400000	USD
	us-gaap	Revenue From Related Parties RevenueFromRelatedParties	456900000	USD
	us-gaap	Revenue From Related Parties RevenueFromRelatedParties	471100000	USD
CY2019Q2	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	697400000	USD
CY2018Q2	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	672000000.0	USD
	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	842800000	USD
	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	841200000	USD
CY2019Q2	clf	Percentage Of Related Party Revenue PercentageOfRelatedPartyRevenue	0.596
CY2018Q2	clf	Percentage Of Related Party Revenue PercentageOfRelatedPartyRevenue	0.609
	clf	Percentage Of Related Party Revenue PercentageOfRelatedPartyRevenue	0.542
	clf	Percentage Of Related Party Revenue PercentageOfRelatedPartyRevenue	0.560
CY2019Q2	us-gaap	Short Term Non Bank Loans And Notes Payable ShortTermNonBankLoansAndNotesPayable	44100000	USD
CY2018Q4	us-gaap	Short Term Non Bank Loans And Notes Payable ShortTermNonBankLoansAndNotesPayable	43500000	USD
CY2019Q2	us-gaap	Related Party Transaction Due From To Related Party RelatedPartyTransactionDueFromToRelatedParty	208700000	USD
CY2018Q4	us-gaap	Related Party Transaction Due From To Related Party RelatedPartyTransactionDueFromToRelatedParty	220000000.0	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	161400000	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	229400000	USD
	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	139300000	USD
	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	216000000.0	USD
CY2019Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-600000	USD
CY2018Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-64300000	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-600000	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-135200000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	160800000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	165100000	USD
	us-gaap	Net Income Loss NetIncomeLoss	138700000	USD
	us-gaap	Net Income Loss NetIncomeLoss	80800000	USD
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	275800000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	297600000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	282600000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	297400000	shares
CY2019Q2	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	6700000	shares
CY2018Q2	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	6900000	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
CY2019Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3000000.0	shares
CY2018Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3700000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	4100000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3700000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	285500000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	301300000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	293600000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	301100000	shares
CY2019Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.59
CY2018Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.77
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.49
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.73
CY2019Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0
CY2018Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.22
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.46
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.59
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.55
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.49
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.27
CY2019Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.57
CY2018Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.76
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.47
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.72
CY2019Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0
CY2018Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.21
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.45
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.57
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.55
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.47
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.27
CY2019Q2	clf	Estimated Project Capital Expenditures EstimatedProjectCapitalExpenditures	830000000	USD
CY2019Q2	us-gaap	Unrecorded Unconditional Purchase Obligation Change Of Amount As Result Of Variable Components UnrecordedUnconditionalPurchaseObligationChangeOfAmountAsResultOfVariableComponents	0.20	USD
CY2019Q2	us-gaap	Unrecorded Unconditional Purchase Obligation Due In Remainder Of Fiscal Year UnrecordedUnconditionalPurchaseObligationDueInRemainderOfFiscalYear	370000000	USD
CY2019Q2	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary	170000000	USD
CY2019Q2	us-gaap	Minority Interest Ownership Percentage By Parent MinorityInterestOwnershipPercentageByParent	1
CY2019Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	377200000	USD
CY2019Q2	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	193100000	USD
CY2019Q2	us-gaap	Inventory Net InventoryNet	219000000.0	USD
CY2019Q2	us-gaap	Supplies Supplies	110800000	USD
CY2019Q2	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	118300000	USD
CY2019Q2	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	58700000	USD
CY2019Q2	us-gaap	Other Assets Current OtherAssetsCurrent	42300000	USD
CY2019Q2	us-gaap	Assets Current AssetsCurrent	1119400000	USD
CY2019Q2	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1597300000	USD
CY2019Q2	us-gaap	Prepaid Expense And Other Assets PrepaidExpenseAndOtherAssets	52200000	USD
CY2019Q2	us-gaap	Income Taxes Receivable Noncurrent IncomeTaxesReceivableNoncurrent	62700000	USD
CY2019Q2	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	443300000	USD
CY2019Q2	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	0	USD
CY2019Q2	clf	Longtermintercompanynotes Longtermintercompanynotes	0	USD
CY2019Q2	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	118300000	USD
CY2019Q2	clf	Total Other Assets TotalOtherAssets	676500000	USD
CY2019Q2	us-gaap	Assets Assets	3393200000	USD
CY2019Q2	us-gaap	Accounts Payable Current AccountsPayableCurrent	188100000	USD
CY2019Q2	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	58400000	USD
CY2019Q2	us-gaap	Interest Payable Current InterestPayableCurrent	31300000	USD
CY2019Q2	us-gaap	Short Term Non Bank Loans And Notes Payable ShortTermNonBankLoansAndNotesPayable	44100000	USD
CY2019Q2	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	115500000	USD
CY2019Q2	us-gaap	Liabilities Current LiabilitiesCurrent	437400000	USD
CY2019Q2	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	239300000	USD
CY2019Q2	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	176700000	USD
CY2019Q2	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2104500000	USD
CY2019Q2	clf	Longtermintercompanynotespayable Longtermintercompanynotespayable	0	USD
CY2019Q2	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	149700000	USD
CY2019Q2	us-gaap	Liabilities Liabilities	3107600000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	285600000	USD
CY2019Q2	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3393200000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	823200000	USD
CY2018Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	226700000	USD
CY2018Q4	us-gaap	Inventory Net InventoryNet	87900000	USD
CY2018Q4	us-gaap	Supplies Supplies	93200000	USD
CY2018Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	91500000	USD
CY2018Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	117300000	USD
CY2018Q4	us-gaap	Other Assets Current OtherAssetsCurrent	39800000	USD
CY2018Q4	us-gaap	Assets Current AssetsCurrent	1479600000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1286000000.0	USD
CY2018Q4	us-gaap	Prepaid Expense And Other Assets PrepaidExpenseAndOtherAssets	83000000.0	USD
CY2018Q4	us-gaap	Income Taxes Receivable Noncurrent IncomeTaxesReceivableNoncurrent	121300000	USD
CY2018Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	464800000	USD
CY2018Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	0	USD
CY2018Q4	clf	Longtermintercompanynotes Longtermintercompanynotes	0	USD
CY2018Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	94900000	USD
CY2018Q4	clf	Total Other Assets TotalOtherAssets	764000000.0	USD
CY2018Q4	us-gaap	Assets Assets	3529600000	USD
CY2018Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	186800000	USD
CY2018Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	74000000.0	USD
CY2018Q4	us-gaap	Interest Payable Current InterestPayableCurrent	38400000	USD
CY2018Q4	us-gaap	Short Term Non Bank Loans And Notes Payable ShortTermNonBankLoansAndNotesPayable	43500000	USD
CY2018Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	125500000	USD
CY2018Q4	us-gaap	Liabilities Current LiabilitiesCurrent	468200000	USD
CY2018Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	248700000	USD
CY2018Q4	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	172000000.0	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2092900000	USD
CY2018Q4	clf	Longtermintercompanynotespayable Longtermintercompanynotespayable	0	USD
CY2018Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	123600000	USD
CY2018Q4	us-gaap	Liabilities Liabilities	3105400000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	424200000	USD
CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3529600000	USD
CY2019Q2	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	697400000	USD
CY2019Q2	clf	Freight Revenue FreightRevenue	45800000	USD
CY2019Q2	us-gaap	Revenues Revenues	743200000	USD
CY2019Q2	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	480200000	USD
CY2019Q2	us-gaap	Gross Profit GrossProfit	263000000.0	USD
CY2019Q2	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	30600000	USD
CY2019Q2	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-5600000	USD
CY2019Q2	us-gaap	Operating Expenses OperatingExpenses	36200000	USD
CY2019Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	226800000	USD
CY2019Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-26100000	USD
CY2019Q2	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-17900000	USD
CY2019Q2	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	600000	USD
CY2019Q2	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-43400000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	183400000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22000000.0	USD
CY2019Q2	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	161400000	USD
CY2019Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-600000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	160800000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3700000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	164500000	USD
CY2018Q2	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	672000000.0	USD
CY2018Q2	clf	Freight Revenue FreightRevenue	42300000	USD
CY2018Q2	us-gaap	Revenues Revenues	714300000	USD
CY2018Q2	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	429800000	USD
CY2018Q2	us-gaap	Gross Profit GrossProfit	284500000	USD
CY2018Q2	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	26200000	USD
CY2018Q2	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-4100000	USD
CY2018Q2	us-gaap	Operating Expenses OperatingExpenses	30300000	USD
CY2018Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	254200000	USD
CY2018Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-31200000	USD
CY2018Q2	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	200000	USD
CY2018Q2	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	4400000	USD
CY2018Q2	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-26600000	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	227600000	USD
CY2018Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-1800000	USD
CY2018Q2	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	229400000	USD
CY2018Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-64300000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	165100000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	9100000	USD
CY2018Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	174200000	USD
	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	842800000	USD
	clf	Freight Revenue FreightRevenue	57400000	USD
	us-gaap	Revenues Revenues	900200000	USD
	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	606300000	USD
	us-gaap	Gross Profit GrossProfit	293900000	USD
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	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-9200000	USD
	us-gaap	Operating Expenses OperatingExpenses	67900000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	226000000.0	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-51200000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-18200000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	1000000.0	USD
	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-68400000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	157600000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18300000	USD
	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	139300000	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	138700000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	12100000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	150800000	USD
	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	841200000	USD
	clf	Freight Revenue FreightRevenue	53100000	USD
	us-gaap	Revenues Revenues	894300000	USD
	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	548300000	USD
	us-gaap	Gross Profit GrossProfit	346000000.0	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	51300000	USD
	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-10200000	USD
	us-gaap	Operating Expenses OperatingExpenses	61500000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	284500000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-63600000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	200000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	8800000	USD
	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-54600000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	229900000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13900000	USD
	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	216000000.0	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-135200000	USD
	us-gaap	Net Income Loss NetIncomeLoss	80800000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	16800000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	97600000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	151100000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	294400000	USD
	clf	Paymentsfor Deposits On Property Plantand Equipment PaymentsforDepositsOnPropertyPlantandEquipment	6500000	USD
	clf	Intercompanyinvestments Intercompanyinvestments	0	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-8500000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-292400000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	252900000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	28900000	USD
	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	720900000	USD
	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	6800000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	729300000	USD
	clf	Intercompanyfinancing Intercompanyfinancing	0	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-10900000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-307900000	USD
	clf	Increase Decreasein Cashand Cash Equivalents Including Cash Classified Within Other Current Assets Relatedto Discontinued Operations IncreaseDecreaseinCashandCashEquivalentsIncludingCashClassifiedWithinOtherCurrentAssetsRelatedtoDiscontinuedOperations	-449200000	USD
	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	3200000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-446000000.0	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	823200000	USD
CY2019Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	377200000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-49300000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	42100000	USD
	clf	Paymentsfor Deposits On Property Plantand Equipment PaymentsforDepositsOnPropertyPlantandEquipment	72300000	USD
	clf	Intercompanyinvestments Intercompanyinvestments	0	USD
	us-gaap	Proceeds From Sale Of Other Assets Investing Activities ProceedsFromSaleOfOtherAssetsInvestingActivities	14600000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-99800000	USD
	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	1500000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	15300000	USD
	clf	Intercompanyfinancing Intercompanyfinancing	0	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-8900000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-25700000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-1000000.0	USD
	clf	Increase Decreasein Cashand Cash Equivalents Including Cash Classified Within Other Current Assets Relatedto Discontinued Operations IncreaseDecreaseinCashandCashEquivalentsIncludingCashClassifiedWithinOtherCurrentAssetsRelatedtoDiscontinuedOperations	-175800000	USD
	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	0	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-175800000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	978300000	USD
CY2018Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	802500000	USD

Files In Submission

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$CLF
CLEVELAND-CLIFFS INC. Stock $clf

2019 Q2 Form 10-Q Financial Statement

#000076406519000134 Filed on July 19, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CLF CLEVELAND-CLIFFS INC. Stock $clf

2019 Q2 Form 10-Q Financial Statement

#000076406519000134 Filed on July 19, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CLF
CLEVELAND-CLIFFS INC. Stock $clf