$CLF
CLEVELAND-CLIFFS INC. Stock $clf

$clf Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-Q Financial Statement

#000076406519000175 Filed on October 23, 2019

Income Statement

Concept	2019 Q4	2019 Q3	2019 Q2
Revenue	$534.1M	$555.6M	$743.2M
YoY Change	-23.29%	-25.1%	4.05%
Cost Of Revenue	$407.2M	$400.7M	$480.2M
YoY Change	-17.45%	-16.56%	11.73%
Gross Profit	$126.9M	$154.9M	$263.0M
YoY Change	-37.18%	-40.79%	-7.56%
Gross Profit Margin	23.76%	27.88%	35.39%
Selling, General & Admin	$37.20M	$25.50M	$29.40M
YoY Change	5.08%	-12.37%	12.21%
% of Gross Profit	29.31%	16.46%	11.18%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$22.00M	$22.00M	$20.90M
YoY Change	7.84%	14.58%	-18.04%
% of Gross Profit	17.34%	14.2%	7.95%
Operating Expenses	$45.20M	$33.30M	$36.20M
YoY Change	14.14%	-7.76%	19.47%
Operating Profit	$81.70M	$121.6M	$226.8M
YoY Change	-49.69%	-46.08%	-10.78%
Interest Expense	-$24.70M	-$25.30M	-$26.10M
YoY Change	-5.0%	-14.24%	-16.61%
% of Operating Profit	-30.23%	-20.81%	-11.51%
Other Income/Expense, Net	$900.0K	-$25.00M	-$43.40M
YoY Change	-78.05%	-0.79%	63.16%
Pretax Income	$57.90M	$96.60M	$183.4M
YoY Change	-56.95%	-51.77%	-19.42%
Income Tax	-$5.500M	$4.800M	$22.00M
% Of Pretax Income	-9.5%	4.97%	12.0%
Net Earnings	$63.20M	$90.90M	$160.8M
YoY Change	-89.63%	-79.24%	-2.6%
Net Earnings / Revenue	11.83%	16.36%	21.64%
Basic Earnings Per Share	$0.23	$0.34	$0.59
Diluted Earnings Per Share	$0.23	$0.33	$0.57
COMMON SHARES
Basic Shares Outstanding	270.1M shares	270.0M shares	275.8M shares
Diluted Shares Outstanding		276.6M shares	285.5M shares

Balance Sheet

Concept	2019 Q4	2019 Q3	2019 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$353.0M	$399.0M	$377.0M
YoY Change	-57.11%	-55.52%	-53.05%
Cash & Equivalents	$353.0M	$399.3M	$377.2M
Short-Term Investments
Other Short-Term Assets	$75.00M	$40.70M	$42.30M
YoY Change	88.44%	116.49%	57.84%
Inventory	$317.0M	$328.0M	$219.0M
Prepaid Expenses
Receivables	$94.00M	$164.9M	$193.1M
Other Receivables	$59.00M	$59.00M	$59.00M
Total Short-Term Assets	$898.0M	$1.065B	$1.119B
YoY Change	-39.31%	-35.5%	-27.64%
LONG-TERM ASSETS
Property, Plant & Equipment	$1.929B	$1.770B	$1.597B
YoY Change	50.0%	54.6%	47.72%
Goodwill	$2.000M
YoY Change
Intangibles	$48.10M
YoY Change
Long-Term Investments
YoY Change
Other Assets	$215.0M	$114.9M	$118.3M
YoY Change	20.85%	-5.35%	0.51%
Total Long-Term Assets	$2.606B	$2.427B	$2.274B
YoY Change	27.12%	64.58%	51.12%
TOTAL ASSETS
Total Short-Term Assets	$898.0M	$1.065B	$1.119B
Total Long-Term Assets	$2.606B	$2.427B	$2.274B
Total Assets	$3.504B	$3.491B	$3.393B
YoY Change	-0.73%	11.72%	11.2%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$193.0M	$212.8M	$188.1M
YoY Change	3.32%	51.14%	58.07%
Accrued Expenses	$126.3M	$91.00M	$90.00M
YoY Change	-20.52%	-4.31%	5.76%
Deferred Revenue			$15.50M
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$409.0M	$458.5M	$437.4M
YoY Change	-12.64%	20.44%	-7.9%
LONG-TERM LIABILITIES
Long-Term Debt	$2.114B	$2.109B	$2.105B
YoY Change	1.01%	-8.3%	-8.38%
Other Long-Term Liabilities	$311.0M	$151.4M	$149.7M
YoY Change	151.62%	24.3%	-5.43%
Total Long-Term Liabilities	$2.425B	$2.261B	$2.254B
YoY Change	9.41%	-6.66%	-8.19%
TOTAL LIABILITIES
Total Short-Term Liabilities	$409.0M	$458.5M	$437.4M
Total Long-Term Liabilities	$2.425B	$2.261B	$2.254B
Total Liabilities	$3.146B	$3.131B	$3.108B
YoY Change	1.31%	-2.49%	-7.45%
SHAREHOLDERS EQUITY
Retained Earnings	-$2.842B	-$2.889B	-$2.953B
YoY Change	-7.13%	-20.95%	-27.85%
Common Stock
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)	$391.0M	$390.9M	$391.3M
YoY Change	110.1%	181.02%	165.29%
Treasury Stock Shares	31.80M shares	31.81M shares	3.879M shares
Shareholders Equity	$358.0M	$359.9M	$285.6M
YoY Change
Total Liabilities & Shareholders Equity	$3.504B	$3.491B	$3.393B
YoY Change	-0.73%	11.72%	11.2%

Cashflow Statement

Concept	2019 Q4	2019 Q3	2019 Q2
OPERATING ACTIVITIES
Net Income	$63.20M	$90.90M	$160.8M
YoY Change	-89.63%	-79.24%	-2.6%
Depreciation, Depletion And Amortization	$22.00M	$22.00M	$20.90M
YoY Change	7.84%	14.58%	-18.04%
Cash From Operating Activities	$175.4M	$238.2M	$263.9M
YoY Change	-40.14%	-5.4%	181.94%
INVESTING ACTIVITIES
Capital Expenditures	-$191.1M	-$153.5M	-$161.7M
YoY Change	96.6%	121.5%	444.44%
Acquisitions
YoY Change
Other Investing Activities	-$3.800M	-$3.600M	-$5.100M
YoY Change	72.73%	-21.74%	-492.31%
Cash From Investing Activities	-$194.9M	-$157.1M	-$166.8M
YoY Change	96.08%	112.58%	487.32%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-27.20M	-59.00M	-150.1M
YoY Change	-89.83%	-28.05%	702.67%
NET CHANGE
Cash From Operating Activities	175.4M	238.2M	263.9M
Cash From Investing Activities	-194.9M	-157.1M	-166.8M
Cash From Financing Activities	-27.20M	-59.00M	-150.1M
Net Change In Cash	-46.70M	22.10M	-53.00M
YoY Change	-36.81%	-76.96%	-213.98%
FREE CASH FLOW
Cash From Operating Activities	$175.4M	$238.2M	$263.9M
Capital Expenditures	-$191.1M	-$153.5M	-$161.7M
Free Cash Flow	$366.5M	$391.7M	$425.6M
YoY Change	-6.07%	21.99%	245.17%

Facts In Submission

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	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2019-09-30
	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
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	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1500000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	90900000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	437800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	229600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	518600000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.34
CY2018Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.67
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.83
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.40
CY2019Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0
CY2018Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0.80
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.01
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0.35
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.34
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.47
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.82
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.75
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.33
CY2018Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.64
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.80
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.37
CY2019Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0
CY2018Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0.77
	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	0.34
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.33
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.41
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.80
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.71
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	269960000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	297878000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	278418000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	297587000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	276578000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	310203000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	287755000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	303518000	shares
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	90900000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	437800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	229600000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-6800000	USD
	clf	Paymentsfor Deposits On Property Plantand Equipment PaymentsforDepositsOnPropertyPlantandEquipment	83300000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-11200000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-21000000.0	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-449500000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-173700000	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	45100000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	0	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-228300000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	400000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	300000	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	1000000.0	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	800000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	6200000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-221200000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	18300000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-204400000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	97100000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	216600000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	247900000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	314200000	USD
	us-gaap	Net Income Loss NetIncomeLoss	229600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	518600000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	63100000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	68600000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	22700000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	0	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	-48400000	USD
	us-gaap	Unrealized Gain Loss On Derivatives And Commodity Contracts UnrealizedGainLossOnDerivativesAndCommodityContracts	136400000	USD
	us-gaap	Foreign Currency Transaction Gain Loss Realized ForeignCurrencyTransactionGainLossRealized	0	USD
	us-gaap	Foreign Currency Transaction Gain Loss Realized ForeignCurrencyTransactionGainLossRealized	228100000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-49400000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-5700000	USD
	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	-156500000	USD
	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	-96200000	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	129400000	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	57100000	USD
	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-70400000	USD
	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-78600000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	388100000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	188700000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	447900000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	111400000	USD
	clf	Paymentsfor Deposits On Property Plantand Equipment PaymentsforDepositsOnPropertyPlantandEquipment	12800000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	729300000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	16300000	USD
	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	0	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	0	USD
	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	720900000	USD
CY2019Q3	us-gaap	Dividends Common Stock DividendsCommonStock	27300000	USD
	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	6800000	USD
	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	1500000	USD
	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	44200000	USD
	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	44200000	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-9500000	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-45700000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-366900000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-107700000	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	-2300000	USD
	clf	Increase Decreasein Cashand Cash Equivalents Including Cash Classified Within Other Current Assets Relatedto Discontinued Operations IncreaseDecreaseinCashandCashEquivalentsIncludingCashClassifiedWithinOtherCurrentAssetsRelatedtoDiscontinuedOperations	-428300000	USD
	clf	Increase Decreasein Cashand Cash Equivalents Including Cash Classified Within Other Current Assets Relatedto Discontinued Operations IncreaseDecreaseinCashandCashEquivalentsIncludingCashClassifiedWithinOtherCurrentAssetsRelatedtoDiscontinuedOperations	-95000000.0	USD
	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	4400000	USD
	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	13800000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-423900000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-81200000	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
CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	399300000	USD
CY2018Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	897100000	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
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	90900000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	6200000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	97100000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	4500000	USD
CY2018Q1	us-gaap	New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Quantification NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification	34000000.0	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	359900000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-444100000	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
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	437800000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-221200000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	216600000	USD
CY2018Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	3500000	USD
CY2018Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-86200000	USD
	us-gaap	Number Of Reporting Units NumberOfReportingUnits	2	unit
	us-gaap	Foreign Currency Transaction Gain Loss Realized ForeignCurrencyTransactionGainLossRealized	228100000	USD
	us-gaap	Number Of Reporting Units NumberOfReportingUnits	2	unit
CY2019Q3	us-gaap	Revenues Revenues	555600000	USD
	us-gaap	Revenues Revenues	1455800000	USD
CY2019Q3	us-gaap	Gross Profit GrossProfit	154900000	USD
	us-gaap	Gross Profit GrossProfit	448800000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	90900000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	437800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	229600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	518600000	USD
CY2019Q3	clf	Ebitda EBITDA	143300000	USD
CY2018Q3	clf	Ebitda EBITDA	487200000	USD
	clf	Ebitda EBITDA	392600000	USD
	clf	Ebitda EBITDA	697100000	USD
CY2019Q3	clf	Adjusted Ebitda AdjustedEBITDA	144100000	USD
CY2018Q3	clf	Adjusted Ebitda AdjustedEBITDA	250300000	USD
	clf	Adjusted Ebitda AdjustedEBITDA	413700000	USD
	clf	Adjusted Ebitda AdjustedEBITDA	578300000	USD
CY2019Q3	clf	Ebitda EBITDA	143300000	USD
CY2018Q3	clf	Ebitda EBITDA	487200000	USD
	clf	Ebitda EBITDA	392600000	USD
	clf	Ebitda EBITDA	697100000	USD
CY2019Q3	clf	Adjusted Ebitda AdjustedEBITDA	144100000	USD
CY2018Q3	clf	Adjusted Ebitda AdjustedEBITDA	250300000	USD
	clf	Adjusted Ebitda AdjustedEBITDA	413700000	USD
	clf	Adjusted Ebitda AdjustedEBITDA	578300000	USD
CY2019Q3	clf	Depreciation Depletionand Amortizationexcluding Depreciation Amortizationand Depletionexpensefor Discontinued Operations DepreciationDepletionandAmortizationexcludingDepreciationAmortizationandDepletionexpenseforDiscontinuedOperations	22200000	USD
CY2018Q3	clf	Depreciation Depletionand Amortizationexcluding Depreciation Amortizationand Depletionexpensefor Discontinued Operations DepreciationDepletionandAmortizationexcludingDepreciationAmortizationandDepletionexpenseforDiscontinuedOperations	19200000	USD
	clf	Depreciation Depletionand Amortizationexcluding Depreciation Amortizationand Depletionexpensefor Discontinued Operations DepreciationDepletionandAmortizationexcludingDepreciationAmortizationandDepletionexpenseforDiscontinuedOperations	63100000	USD
	clf	Depreciation Depletionand Amortizationexcluding Depreciation Amortizationand Depletionexpensefor Discontinued Operations DepreciationDepletionandAmortizationexcludingDepreciationAmortizationandDepletionexpenseforDiscontinuedOperations	53400000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	184700000	USD
CY2018Q3	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	92600000	USD
	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	505600000	USD
	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	241900000	USD
CY2019Q3	us-gaap	Assets Assets	3491200000	USD
CY2018Q4	us-gaap	Assets Assets	3529600000	USD
	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	42800000	USD
CY2018	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	51300000	USD
CY2019Q3	us-gaap	Financial Liabilities Fair Value Disclosure FinancialLiabilitiesFairValueDisclosure	32600000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	543400000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	2851700000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	2308400000	USD
CY2019Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1081800000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1022400000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1769900000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1286000000.0	USD
CY2019Q3	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	7000000.0	USD
	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	16900000	USD
CY2018Q3	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	1800000	USD
	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	3900000	USD
CY2019Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2109100000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2092900000	USD
	us-gaap	Extinguishment Of Debt Amount ExtinguishmentOfDebtAmount	724000000.0	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-18200000	USD
CY2019Q3	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	32600000	USD
CY2018Q3	us-gaap	Extinguishment Of Debt Amount ExtinguishmentOfDebtAmount	1000000.0	USD
CY2018Q3	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
	us-gaap	Extinguishment Of Debt Amount ExtinguishmentOfDebtAmount	16500000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	200000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal Remainder Of Fiscal Year LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear	0	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	0	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	0	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	0	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	0	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	400000000.0	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1838000000.0	USD
CY2019Q3	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	2238000000.0	USD
CY2019Q3	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	272500000	USD
CY2019Q3	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	72800000	USD
CY2019Q3	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	345300000	USD
CY2019Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	72800000	USD
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	190600000	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 Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	3700000	USD
CY2018Q4	us-gaap	Financial Liabilities Fair Value Disclosure FinancialLiabilitiesFairValueDisclosure	3700000	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
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
CY2019Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	6500000	USD
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-139000000.0	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-83100000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-341800000	USD
CY2019Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	38800000	USD
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	123000000.0	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	101700000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	200700000	USD
CY2019Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	72800000	USD
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	190600000	USD
CY2018Q4	clf	Mine Reclamation And Closing Liability Current And Noncurrent MineReclamationAndClosingLiabilityCurrentAndNoncurrent	174900000	USD
CY2019Q3	us-gaap	Accrued Reclamation Costs Current AccruedReclamationCostsCurrent	2500000	USD
CY2018Q4	us-gaap	Accrued Reclamation Costs Current AccruedReclamationCostsCurrent	2900000	USD
CY2019Q3	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	179100000	USD
CY2018Q4	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	172000000.0	USD
CY2019Q3	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-6500000	USD
CY2018Q3	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	15900000	USD
	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	81800000	USD
	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	141000000.0	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
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
CY2019Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	-34400000	USD
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	-3100000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	-39700000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	-7400000	USD
CY2019Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	4200000	USD
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	400000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	9500000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	3400000	USD
CY2019Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	30200000	USD
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	5700000	USD
CY2019Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	30200000	USD
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	5700000	USD
CY2019Q3	us-gaap	Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-30200000	USD
CY2018Q3	us-gaap	Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-2700000	USD
	us-gaap	Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-30200000	USD
	us-gaap	Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-5700000	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	0.096
	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
CY2019Q3	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-500000	USD
	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-1300000	USD
CY2018Q3	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-200000	USD
	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-13900000	USD
	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-13900000	USD
	clf	Repealof Am Tamount RepealofAMTamount	14500000	USD
CY2019Q3	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	2100000	USD
CY2018Q4	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	2500000	USD
CY2019Q3	clf	Mine Reclamation And Closing Liability Current And Noncurrent MineReclamationAndClosingLiabilityCurrentAndNoncurrent	181600000	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	7600000	USD
CY2018	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	9500000	USD
	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	500000	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
CY2019Q3	us-gaap	Asset Retirement Obligation AssetRetirementObligation	179500000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	172400000	USD
CY2019Q3	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	72800000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	91500000	USD
CY2019Q3	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	32600000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	3700000	USD
CY2019Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-900000	USD
CY2018Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	238000000.0	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1500000	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	102800000	USD
	us-gaap	Noncash Investing And Financing Activities Related Text NoncashInvestingAndFinancingActivitiesRelatedText	For the nine months ended September 30, 2018, we had $27.1 million of non-cash financing activities related to the release of asset retirement obligations at Asia Pacific Iron Ore as part of the sale of substantially all remaining assets.
CY2018Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	200000000	USD
CY2019Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	100000000	USD
	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	24400000	shares
	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	252900000	USD
CY2019Q3	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	200000	USD
	us-gaap	Property Plant And Equipment Additions PropertyPlantAndEquipmentAdditions	505600000	USD
	clf	Property Plantand Equipment Additions Including Discontinued Operations PropertyPlantandEquipmentAdditionsIncludingDiscontinuedOperations	242000000.0	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	-26100000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	-42200000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	29300000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	7600000	USD
	clf	Governmentgrantrebate Governmentgrantrebate	-10500000	USD
	clf	Governmentgrantrebate Governmentgrantrebate	-2500000	USD
	clf	Payments To Acquire Property Plant And Equipment Net PaymentsToAcquirePropertyPlantAndEquipmentNet	-460700000	USD
	clf	Payments To Acquire Property Plant And Equipment Net PaymentsToAcquirePropertyPlantAndEquipmentNet	-194700000	USD
CY2019Q3	us-gaap	Dividends Payable Current DividendsPayableCurrent	27000000.0	USD
	us-gaap	Net Income Loss NetIncomeLoss	229600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	518600000	USD
CY2019Q3	clf	Percentage Of Related Party Revenue PercentageOfRelatedPartyRevenue	0.509
CY2018Q3	clf	Percentage Of Related Party Revenue PercentageOfRelatedPartyRevenue	0.573
	clf	Percentage Of Related Party Revenue PercentageOfRelatedPartyRevenue	0.529
	clf	Percentage Of Related Party Revenue PercentageOfRelatedPartyRevenue	0.566
CY2019Q3	us-gaap	Short Term Non Bank Loans And Notes Payable ShortTermNonBankLoansAndNotesPayable	0	USD
CY2018Q4	us-gaap	Short Term Non Bank Loans And Notes Payable ShortTermNonBankLoansAndNotesPayable	43500000	USD
CY2019Q3	us-gaap	Related Party Transaction Due From To Related Party RelatedPartyTransactionDueFromToRelatedParty	152600000	USD
CY2018Q4	us-gaap	Related Party Transaction Due From To Related Party RelatedPartyTransactionDueFromToRelatedParty	220000000.0	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	91800000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	199800000	USD
	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	231100000	USD
	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	415800000	USD
CY2019Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-900000	USD
CY2018Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	238000000.0	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1500000	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	102800000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	90900000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	437800000	USD
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	270000000.0	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	297900000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	278400000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	297600000	shares
CY2019Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	3700000	shares
CY2018Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	8000000.0	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	5800000	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	1900000	shares
CY2019Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	2900000	shares
CY2018Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	4300000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3600000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	4000000.0	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	276600000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	310200000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	287800000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	303500000	shares
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.34
CY2018Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.67
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.83
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.40
CY2019Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0
CY2018Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0.80
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.01
	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0.35
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.34
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.47
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.82
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.75
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.33
CY2018Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.64
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.80
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.37
CY2019Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0
CY2018Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0.77
	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	0.34
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.33
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.41
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.80
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.71
CY2019Q3	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	32600000	USD
CY2019Q3	us-gaap	Short Term Non Bank Loans And Notes Payable ShortTermNonBankLoansAndNotesPayable	0	USD
CY2019Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	121700000	USD
CY2019Q3	us-gaap	Liabilities Current LiabilitiesCurrent	458500000	USD
CY2019Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	233200000	USD
CY2019Q3	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	179100000	USD
CY2019Q3	clf	Estimated Project Capital Expenditures EstimatedProjectCapitalExpenditures	830000000	USD
CY2019Q3	clf	Project Spend Contingency Percentage ProjectSpendContingencyPercentage	0.20
CY2019Q3	us-gaap	Unrecorded Unconditional Purchase Obligation Due In Remainder Of Fiscal Year UnrecordedUnconditionalPurchaseObligationDueInRemainderOfFiscalYear	180000000	USD
CY2019Q3	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary	245000000	USD
CY2019Q3	us-gaap	Minority Interest Ownership Percentage By Parent MinorityInterestOwnershipPercentageByParent	1
CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	399300000	USD
CY2019Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	164900000	USD
CY2019Q3	us-gaap	Inventory Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	162200000	USD
CY2019Q3	us-gaap	Inventory Work In Process Net Of Reserves InventoryWorkInProcessNetOfReserves	55200000	USD
CY2019Q3	us-gaap	Supplies Supplies	110800000	USD
CY2019Q3	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	72800000	USD
CY2019Q3	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	58700000	USD
CY2019Q3	us-gaap	Other Assets Current OtherAssetsCurrent	40700000	USD
CY2019Q3	us-gaap	Assets Current AssetsCurrent	1064600000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1769900000	USD
CY2019Q3	us-gaap	Prepaid Expense And Other Assets PrepaidExpenseAndOtherAssets	41600000	USD
CY2019Q3	us-gaap	Income Taxes Receivable Noncurrent IncomeTaxesReceivableNoncurrent	62700000	USD
CY2019Q3	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	437500000	USD
CY2019Q3	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	0	USD
CY2019Q3	clf	Longtermintercompanynotes Longtermintercompanynotes	0	USD
CY2019Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	114900000	USD
CY2019Q3	clf	Total Other Assets TotalOtherAssets	656700000	USD
CY2019Q3	us-gaap	Assets Assets	3491200000	USD
CY2019Q3	us-gaap	Accounts Payable Current AccountsPayableCurrent	212800000	USD
CY2019Q3	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	57300000	USD
CY2019Q3	us-gaap	Interest Payable Current InterestPayableCurrent	34100000	USD
CY2019Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2109100000	USD
CY2019Q3	clf	Longtermintercompanynotespayable Longtermintercompanynotespayable	0	USD
CY2019Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	151400000	USD
CY2019Q3	us-gaap	Liabilities Liabilities	3131300000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	359900000	USD
CY2019Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3491200000	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 Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	77800000	USD
CY2018Q4	us-gaap	Inventory Work In Process Net Of Reserves InventoryWorkInProcessNetOfReserves	10100000	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	Derivative Liabilities Current DerivativeLiabilitiesCurrent	3700000	USD
CY2018Q4	us-gaap	Short Term Non Bank Loans And Notes Payable ShortTermNonBankLoansAndNotesPayable	43500000	USD
CY2018Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	121800000	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
CY2019Q3	us-gaap	Revenues Revenues	555600000	USD
CY2019Q3	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	400700000	USD
CY2019Q3	us-gaap	Gross Profit GrossProfit	154900000	USD
CY2019Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	25500000	USD
CY2019Q3	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-7800000	USD
CY2019Q3	us-gaap	Operating Expenses OperatingExpenses	33300000	USD
CY2019Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	121600000	USD
CY2019Q3	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-25300000	USD
CY2019Q3	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	300000	USD
CY2019Q3	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-25000000.0	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	96600000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4800000	USD
CY2019Q3	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	91800000	USD
CY2019Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-900000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	90900000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	6200000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	97100000	USD
CY2018Q3	us-gaap	Revenues Revenues	741800000	USD
CY2018Q3	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	480200000	USD
CY2018Q3	us-gaap	Gross Profit GrossProfit	261600000	USD
CY2018Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	29100000	USD
CY2018Q3	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-7000000.0	USD
CY2018Q3	us-gaap	Operating Expenses OperatingExpenses	36100000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	225500000	USD
CY2018Q3	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-29500000	USD
CY2018Q3	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	4300000	USD
CY2018Q3	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-25200000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	200300000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	500000	USD
CY2018Q3	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	199800000	USD
CY2018Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	238000000.0	USD
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CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-221200000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	216600000	USD
	us-gaap	Revenues Revenues	1455800000	USD
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	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	82200000	USD
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	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-76500000	USD
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	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	1300000	USD
	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-93400000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	254200000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	23100000	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	231100000	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1500000	USD
	us-gaap	Net Income Loss NetIncomeLoss	229600000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	18300000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	247900000	USD
	us-gaap	Revenues Revenues	1636100000	USD
	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	1028500000	USD
	us-gaap	Gross Profit GrossProfit	607600000	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	78900000	USD
	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-18700000	USD
	us-gaap	Operating Expenses OperatingExpenses	97600000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	510000000.0	USD
	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-93100000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	200000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	13100000	USD
	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-79800000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	430200000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14400000	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	415800000	USD
	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	102800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	518600000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-204400000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	314200000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	388100000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	447900000	USD
	clf	Paymentsfor Deposits On Property Plantand Equipment PaymentsforDepositsOnPropertyPlantandEquipment	12800000	USD
	clf	Intercompanyinvestments Intercompanyinvestments	0	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-11200000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-449500000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	252900000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	45100000	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
	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	44200000	USD
	clf	Intercompanyfinancing Intercompanyfinancing	0	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-9500000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-366900000	USD
	clf	Increase Decreasein Cashand Cash Equivalents Including Cash Classified Within Other Current Assets Relatedto Discontinued Operations IncreaseDecreaseinCashandCashEquivalentsIncludingCashClassifiedWithinOtherCurrentAssetsRelatedtoDiscontinuedOperations	-428300000	USD
	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	4400000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-423900000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	823200000	USD
CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	399300000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	188700000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	111400000	USD
	clf	Paymentsfor Deposits On Property Plantand Equipment PaymentsforDepositsOnPropertyPlantandEquipment	83300000	USD
	clf	Intercompanyinvestments Intercompanyinvestments	0	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-21000000.0	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-173700000	USD
	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	1500000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	16300000	USD
	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	44200000	USD
	clf	Intercompanyfinancing Intercompanyfinancing	0	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-45700000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-107700000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-2300000	USD
	clf	Increase Decreasein Cashand Cash Equivalents Including Cash Classified Within Other Current Assets Relatedto Discontinued Operations IncreaseDecreaseinCashandCashEquivalentsIncludingCashClassifiedWithinOtherCurrentAssetsRelatedtoDiscontinuedOperations	-95000000.0	USD
	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	13800000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-81200000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	978300000	USD
CY2018Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	897100000	USD

Files In Submission

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$CLF
CLEVELAND-CLIFFS INC. Stock $clf

2019 Q4 Form 10-Q Financial Statement

#000076406519000175 Filed on October 23, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CLF CLEVELAND-CLIFFS INC. Stock $clf

2019 Q4 Form 10-Q Financial Statement

#000076406519000175 Filed on October 23, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CLF
CLEVELAND-CLIFFS INC. Stock $clf