$ARCH
ARCH RESOURCES, INC. Stock $arch

$arch Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-K Financial Statement

#000155837022001243 Filed on February 16, 2022

Income Statement

Concept	2021 Q4	2021	2020 Q4
Revenue	$805.7M	$2.208B	$360.6M
YoY Change	123.43%	50.45%	-34.37%
Cost Of Revenue	$490.8M	$1.580B	$341.6M
YoY Change	43.67%	14.61%	-30.64%
Gross Profit	$314.9M	$367.1M	$19.00M
YoY Change	1557.48%	-211.2%	-17.91%
Gross Profit Margin	39.09%	16.63%	5.27%
Selling, General & Admin	$25.66M	$92.34M	$18.40M
YoY Change	39.47%	12.07%	-15.98%
% of Gross Profit	8.15%	25.15%	96.84%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$35.89M	$120.3M	$27.50M
YoY Change	30.49%	-1.01%	-8.03%
% of Gross Profit	11.4%	32.78%	144.74%
Operating Expenses	$83.16M	$92.34M	$45.30M
YoY Change	83.57%	12.07%	-2.79%
Operating Profit	$231.8M	$343.8M	-$26.30M
YoY Change	-981.24%	-200.89%	277.87%
Interest Expense	$20.73M	$23.97M	-$6.200M
YoY Change	-434.27%	66.1%	93.75%
% of Operating Profit	8.94%	6.97%
Other Income/Expense, Net	-$1.087M	-$4.339M	-$800.0K
YoY Change	35.88%	12.47%	-900.0%
Pretax Income	$227.2M	$339.4M	-$78.30M
YoY Change	-390.14%	-198.5%	789.77%
Income Tax	$573.0K	$1.874M	$200.0K
% Of Pretax Income	0.25%	0.55%
Net Earnings	$226.6M	$337.6M	-$78.50M
YoY Change	-388.67%	-197.96%	818.02%
Net Earnings / Revenue	28.13%	15.29%	-21.77%
Basic Earnings Per Share		$22.04
Diluted Earnings Per Share	$11.92M	$19.20	-$5.164M
COMMON SHARES
Basic Shares Outstanding	15.32M	15.32M	15.15M
Diluted Shares Outstanding		17.58M

Balance Sheet

Concept	2021 Q4	2021	2020 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$339.7M	$339.7M	$284.3M
YoY Change	19.49%	19.6%	-1.53%
Cash & Equivalents	$325.2M	$325.2M	$187.5M
Short-Term Investments	$14.46M	$14.46M	$96.77M
Other Short-Term Assets	$52.80M	$53.91M	$58.00M
YoY Change	-8.96%	-15.77%	-40.75%
Inventory	$156.7M	$156.7M	$126.0M
Prepaid Expenses
Receivables	$324.3M	$324.3M	$110.9M
Other Receivables	$8.271M	$8.271M	$3.000M
Total Short-Term Assets	$882.9M	$882.9M	$588.1M
YoY Change	50.11%	50.15%	-16.78%
LONG-TERM ASSETS
Property, Plant & Equipment	$1.120B	$1.139B	$1.007B
YoY Change	11.19%	10.57%	2.32%
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments	$15.40M	$15.40M	$71.78M
YoY Change	-78.54%	-78.61%	-32.02%
Other Assets	$78.84M	$79.98M	$55.25M
YoY Change	42.71%	142.37%	-22.09%
Total Long-Term Assets	$1.234B	$1.234B	$1.134B
YoY Change	8.81%	8.84%	-2.3%
TOTAL ASSETS
Total Short-Term Assets	$882.9M	$882.9M	$588.1M
Total Long-Term Assets	$1.234B	$1.234B	$1.134B
Total Assets	$2.117B	$2.117B	$1.722B
YoY Change	22.91%	22.95%	-7.78%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$132.0M	$132.0M	$103.7M
YoY Change	27.22%	26.91%	-22.03%
Accrued Expenses	$167.3M	$166.4M	$155.3M
YoY Change	7.76%	8.04%	-1.22%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$224.0M	$224.0M	$32.00M
YoY Change	599.9%	599.9%	52.38%
Total Short-Term Liabilities	$522.3M	$522.3M	$290.1M
YoY Change	80.06%	80.12%	-6.72%
LONG-TERM LIABILITIES
Long-Term Debt	$337.6M	$341.7M	$477.2M
YoY Change	-29.25%	-29.1%	64.52%
Other Long-Term Liabilities	$81.69M	$569.2M	$98.91M
YoY Change	-17.41%	-14.66%	20.47%
Total Long-Term Liabilities	$419.3M	$911.0M	$576.1M
YoY Change	-27.22%	-20.72%	54.8%
TOTAL LIABILITIES
Total Short-Term Liabilities	$522.3M	$522.3M	$290.1M
Total Long-Term Liabilities	$419.3M	$911.0M	$576.1M
Total Liabilities	$1.433B	$1.433B	$1.439B
YoY Change	-0.39%	-0.4%	17.25%
SHAREHOLDERS EQUITY
Retained Earnings	$712.5M		$378.9M
YoY Change	88.04%		-48.2%
Common Stock	$784.6M		$767.7M
YoY Change	2.2%		5.05%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$827.4M		$827.4M
YoY Change	0.0%		0.0%
Treasury Stock Shares	$10.09M		$10.09M
Shareholders Equity	$683.9M	$683.9M	$283.6M
YoY Change
Total Liabilities & Shareholders Equity	$2.117B	$2.117B	$1.722B
YoY Change	22.91%	22.95%	-7.78%

Cashflow Statement

Concept	2021 Q4	2021	2020 Q4
OPERATING ACTIVITIES
Net Income	$226.6M	$337.6M	-$78.50M
YoY Change	-388.67%	-197.96%	818.02%
Depreciation, Depletion And Amortization	$35.89M	$120.3M	$27.50M
YoY Change	30.49%	-1.01%	-8.03%
Cash From Operating Activities	$146.7M	$238.3M	$5.200M
YoY Change	2721.19%	289.95%	-93.93%
INVESTING ACTIVITIES
Capital Expenditures	-$33.39M	$245.4M	-$80.30M
YoY Change	-58.41%	-14.13%	-37.75%
Acquisitions
YoY Change
Other Investing Activities	$25.01M	$105.4M	-$33.80M
YoY Change	-174.0%	72.52%	-176.99%
Cash From Investing Activities	-$8.381M	-$141.2M	-$114.1M
YoY Change	-92.65%	-37.52%	34.08%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-2.834M	35.78M	131.7M
YoY Change	-102.15%	-82.57%	-675.11%
NET CHANGE
Cash From Operating Activities	146.7M	238.3M	5.200M
Cash From Investing Activities	-8.381M	-141.2M	-114.1M
Cash From Financing Activities	-2.834M	35.78M	131.7M
Net Change In Cash	135.5M	132.9M	22.80M
YoY Change	494.24%	228.63%	-201.79%
FREE CASH FLOW
Cash From Operating Activities	$146.7M	$238.3M	$5.200M
Capital Expenditures	-$33.39M	$245.4M	-$80.30M
Free Cash Flow	$180.1M	-$7.156M	$85.50M
YoY Change	110.64%	-96.82%	-60.16%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value
CY2021	dei	Entity Central Index Key EntityCentralIndexKey	0001037676
CY2021	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
CY2021	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#OtherAssetsNoncurrent
CY2021Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#OtherAssetsNoncurrent
CY2021Q4	us-gaap	Finance Lease Liability Current Statement Of Financial Position Extensible List FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#AccruedLiabilitiesCurrent
CY2021Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#AccruedLiabilitiesCurrent
CY2021Q4	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#OtherLiabilitiesNoncurrent
CY2021Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#OtherLiabilitiesNoncurrent
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#OtherAssetsNoncurrent
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#OtherAssetsNoncurrent
CY2020Q4	us-gaap	Finance Lease Liability Current Statement Of Financial Position Extensible List FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#AccruedLiabilitiesCurrent
CY2020Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#AccruedLiabilitiesCurrent
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#OtherLiabilitiesNoncurrent
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#OtherLiabilitiesNoncurrent
CY2021	aci	Long Term Contracts Life Term Minimum LongTermContractsLifeTermMinimum	P1Y
CY2021	dei	Amendment Flag AmendmentFlag	false
CY2021	dei	Document Type DocumentType	10-K
CY2021	dei	Document Annual Report DocumentAnnualReport	true
CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-12-31
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021	dei	Document Transition Report DocumentTransitionReport	false
CY2021	dei	Entity File Number EntityFileNumber	1-13105
CY2021	dei	Entity Registrant Name EntityRegistrantName	Arch Resources, Inc.
CY2021	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2021	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	43-0921172
CY2021	dei	Entity Address Address Line1 EntityAddressAddressLine1	1 CityPlace Drive
CY2021	dei	Entity Address Address Line2 EntityAddressAddressLine2	Suite 300
CY2021	dei	Entity Address City Or Town EntityAddressCityOrTown	St. Louis
CY2021	dei	Entity Address State Or Province EntityAddressStateOrProvince	MO
CY2021	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	63141
CY2021	dei	City Area Code CityAreaCode	314
CY2021	dei	Local Phone Number LocalPhoneNumber	994-2700
CY2021	dei	Security12b Title Security12bTitle	Common Stock, $.01 par value
CY2021	dei	Trading Symbol TradingSymbol	ARCH
CY2021	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2021	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2021	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2021	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2021	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2021	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2021	dei	Entity Small Business EntitySmallBusiness	false
CY2021	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2021	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2021	dei	Entity Shell Company EntityShellCompany	false
CY2021Q2	dei	Entity Public Float EntityPublicFloat	871400000
CY2022Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	15393053
CY2021	dei	Auditor Firm AuditorFirmId	42
CY2021	dei	Auditor Name AuditorName	Ernst & Young LLP
CY2021	dei	Auditor Location AuditorLocation	St. Louis, Missouri
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2208042000
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1467592000
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2294352000
CY2021	us-gaap	Cost Of Goods And Service Excluding Depreciation Depletion And Amortization CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization	1579836000
CY2020	us-gaap	Cost Of Goods And Service Excluding Depreciation Depletion And Amortization CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization	1378479000
CY2019	us-gaap	Cost Of Goods And Service Excluding Depreciation Depletion And Amortization CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization	1873017000
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	120327000
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	121552000
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	111621000
CY2021	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	21748000
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	19887000
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	20548000
CY2021	aci	Change In Fair Value Of Coal Derivatives And Coal Trading Activities Net ChangeInFairValueOfCoalDerivativesAndCoalTradingActivitiesNet	-2392000
CY2020	aci	Change In Fair Value Of Coal Derivatives And Coal Trading Activities Net ChangeInFairValueOfCoalDerivativesAndCoalTradingActivitiesNet	5219000
CY2019	aci	Change In Fair Value Of Coal Derivatives And Coal Trading Activities Net ChangeInFairValueOfCoalDerivativesAndCoalTradingActivitiesNet	-18601000
CY2021	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	92342000
CY2020	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	82397000
CY2019	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	95781000
CY2020	aci	Operating Income Expense Related To Joint Venture OperatingIncomeExpenseRelatedToJointVenture	16087000
CY2019	aci	Operating Income Expense Related To Joint Venture OperatingIncomeExpenseRelatedToJointVenture	13816000
CY2020	aci	Asset Impairment Charges And Mine Closure Costs AssetImpairmentChargesAndMineClosureCosts	221380000
CY2020	us-gaap	Gain On Business Interruption Insurance Recovery GainOnBusinessInterruptionInsuranceRecovery	23518000
CY2021	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	-24225000
CY2020	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	1505000
CY2019	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	-13312000
CY2019	us-gaap	Gain Loss Related To Litigation Settlement GainLossRelatedToLitigationSettlement	39000000
CY2021	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-4826000
CY2020	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	22246000
CY2019	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	19012000
CY2021	aci	Operating Cost Expenses And Others OperatingCostExpensesAndOthers	1840912000
CY2020	aci	Operating Cost Expenses And Others OperatingCostExpensesAndOthers	1797732000
CY2019	aci	Operating Cost Expenses And Others OperatingCostExpensesAndOthers	2051482000
CY2021	us-gaap	Gross Profit GrossProfit	367130000
CY2020	us-gaap	Gross Profit GrossProfit	-330140000
CY2019	us-gaap	Gross Profit GrossProfit	242870000
CY2021	us-gaap	Interest Expense InterestExpense	23972000
CY2020	us-gaap	Interest Expense InterestExpense	14432000
CY2019	us-gaap	Interest Expense InterestExpense	16485000
CY2021	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	628000
CY2020	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	3808000
CY2019	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	9691000
CY2021	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-23344000
CY2020	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-10624000
CY2019	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-6794000
CY2021	us-gaap	Operating Income Loss OperatingIncomeLoss	343786000
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	-340764000
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	14.42
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	236076000
CY2021	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	4339000
CY2020	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	3884000
CY2019	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	2053000
CY2020	us-gaap	Nondebtor Reorganization Items Net Gain Loss On Settlement Of Other Claims1 NondebtorReorganizationItemsNetGainLossOnSettlementOfOtherClaims1	26000
CY2019	us-gaap	Nondebtor Reorganization Items Net Gain Loss On Settlement Of Other Claims1 NondebtorReorganizationItemsNetGainLossOnSettlementOfOtherClaims1	24000
CY2021	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-4339000
CY2020	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-3858000
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-2029000
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	339447000
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-344622000
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	234047000
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1874000
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-7000
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	248000
CY2021	us-gaap	Net Income Loss NetIncomeLoss	337573000
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-344615000
CY2019	us-gaap	Net Income Loss NetIncomeLoss	233799000
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	22.04
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-22.74
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	19.20
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-22.74
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	13.52
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15318000
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15153000
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16218000
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	17579000
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	15153000
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	17298000
CY2021	us-gaap	Net Income Loss NetIncomeLoss	337573000
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-344615000
CY2019	us-gaap	Net Income Loss NetIncomeLoss	233799000
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent	2128000
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent	-1328000
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent	-5892000
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	2128000
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-1328000
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CY2021	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent	-47562000
CY2020	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent	39732000
CY2019	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent	32038000
CY2021	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	-47562000
CY2020	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	39732000
CY2019	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	32038000
CY2021	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent	169000
CY2020	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent	-330000
CY2019	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent	323000
CY2021	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	169000
CY2020	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	-330000
CY2019	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	323000
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	49859000
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-41390000
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-37607000
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	387432000
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-386005000
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	196192000
CY2021Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	325194000
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	187492000
CY2021Q4	us-gaap	Available For Sale Securities Debt Securities Current AvailableForSaleSecuritiesDebtSecuritiesCurrent	14463000
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities Current AvailableForSaleSecuritiesDebtSecuritiesCurrent	96765000
CY2021Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	1101000
CY2020Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	5953000
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	0
CY2021Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	0
CY2021Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	324304000
CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	110869000
CY2021Q4	us-gaap	Other Receivables OtherReceivables	8271000
CY2020Q4	us-gaap	Other Receivables OtherReceivables	3053000
CY2021Q4	us-gaap	Inventory Net InventoryNet	156734000
CY2020Q4	us-gaap	Inventory Net InventoryNet	126008000
CY2021Q4	us-gaap	Other Assets Current OtherAssetsCurrent	52804000
CY2020Q4	us-gaap	Other Assets Current OtherAssetsCurrent	58000000
CY2021Q4	us-gaap	Assets Current AssetsCurrent	882871000
CY2020Q4	us-gaap	Assets Current AssetsCurrent	588140000
CY2021Q4	aci	Coal Lands And Mineral Rights CoalLandsAndMineralRights	406822000
CY2020Q4	aci	Coal Lands And Mineral Rights CoalLandsAndMineralRights	406095000
CY2021Q4	us-gaap	Property Plant And Equipment Other PropertyPlantAndEquipmentOther	844107000
CY2020Q4	us-gaap	Property Plant And Equipment Other PropertyPlantAndEquipmentOther	734194000
CY2021Q4	aci	Deferred Mine Development DeferredMineDevelopment	402470000
CY2020Q4	aci	Deferred Mine Development DeferredMineDevelopment	288693000
CY2021Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1653399000
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1428982000
CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	533356000
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	421679000
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1120043000
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1007303000
CY2021Q4	us-gaap	Equity Method Investments EquityMethodInvestments	15403000
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	71783000
CY2021Q4	aci	Sinking Fund For Asset Retirement Obligation Non Current SinkingFundForAssetRetirementObligationNonCurrent	20000000
CY2021Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	78843000
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	55246000
CY2021Q4	aci	Other Assets Non Current Total OtherAssetsNonCurrentTotal	114246000
CY2020Q4	aci	Other Assets Non Current Total OtherAssetsNonCurrentTotal	127029000
CY2021Q4	us-gaap	Assets Assets	2117160000
CY2020Q4	us-gaap	Assets Assets	1722472000
CY2021Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	131986000
CY2020Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	103743000
CY2021Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	167304000
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	155256000
CY2021Q4	us-gaap	Debt Current DebtCurrent	223050000
CY2020Q4	us-gaap	Debt Current DebtCurrent	31097000
CY2021Q4	us-gaap	Liabilities Current LiabilitiesCurrent	522340000
CY2020Q4	us-gaap	Liabilities Current LiabilitiesCurrent	290096000
CY2021Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	337623000
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	477215000
CY2021Q4	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	192672000
CY2020Q4	us-gaap	Mine Reclamation And Closing Liability Noncurrent MineReclamationAndClosingLiabilityNoncurrent	230732000
CY2021Q4	us-gaap	Defined Benefit Pension Plan Liabilities Noncurrent DefinedBenefitPensionPlanLiabilitiesNoncurrent	1300000
CY2020Q4	us-gaap	Defined Benefit Pension Plan Liabilities Noncurrent DefinedBenefitPensionPlanLiabilitiesNoncurrent	2879000
CY2021Q4	us-gaap	Other Postretirement Defined Benefit Plan Liabilities Noncurrent OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent	73565000
CY2020Q4	us-gaap	Other Postretirement Defined Benefit Plan Liabilities Noncurrent OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent	94388000
CY2021Q4	us-gaap	Workers Compensation Liability Noncurrent WorkersCompensationLiabilityNoncurrent	224105000
CY2020Q4	us-gaap	Workers Compensation Liability Noncurrent WorkersCompensationLiabilityNoncurrent	244695000
CY2021Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	81689000
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	98906000
CY2021Q4	us-gaap	Liabilities Liabilities	1433294000
CY2020Q4	us-gaap	Liabilities Liabilities	1438911000
CY2020Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2021Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	300000000
CY2021Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	300000000
CY2021Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	25481000
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	25323000
CY2021Q4	us-gaap	Common Stock Value CommonStockValue	255000
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	253000
CY2021Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	784356000
CY2020Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	767484000
CY2021Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	712478000
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	378906000
CY2020Q4	us-gaap	Treasury Stock Common Shares TreasuryStockCommonShares	10088000
CY2021Q4	us-gaap	Treasury Stock Common Shares TreasuryStockCommonShares	10088000
CY2021Q4	us-gaap	Treasury Stock Value TreasuryStockValue	827381000
CY2020Q4	us-gaap	Treasury Stock Value TreasuryStockValue	827381000
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	14158000
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-35701000
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	683866000
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	283561000
CY2021Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	2117160000
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	1722472000
CY2021	us-gaap	Profit Loss ProfitLoss	337573000
CY2020	us-gaap	Profit Loss ProfitLoss	-344615000
CY2019	us-gaap	Profit Loss ProfitLoss	233799000
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	120327000
CY2021	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-8000
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	121552000
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	111621000
CY2021	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	21748000
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	19887000
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	20548000
CY2020	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-14430000
CY2019	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-13501000
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	20539000
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	17435000
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	21989000
CY2021	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	6549000
CY2020	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	5599000
CY2019	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	3691000
CY2020	us-gaap	Gain On Business Interruption Insurance Recovery GainOnBusinessInterruptionInsuranceRecovery	23518000
CY2021	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	-23276000
CY2020	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	3727000
CY2019	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	-8304000
CY2021	aci	Reclamation Amount Recognized ReclamationAmountRecognized	39047000
CY2020	aci	Reclamation Amount Recognized ReclamationAmountRecognized	14357000
CY2019	aci	Reclamation Amount Recognized ReclamationAmountRecognized	8832000
CY2021	aci	Contribution To Sinking Fund For Asset Retirement Obligations ContributionToSinkingFundForAssetRetirementObligations	20000000
CY2020	aci	Non Cash Asset Impairment Charges And Mine Closure Costs NonCashAssetImpairmentChargesAndMineClosureCosts	198007000
CY2019	us-gaap	Gain Loss Related To Litigation Settlement GainLossRelatedToLitigationSettlement	39000000
CY2021	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	212950000
CY2020	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-63657000
CY2019	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-30713000
CY2021	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	30726000
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	9126000
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	15251000
CY2021	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	45547000
CY2020	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	-46066000
CY2019	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	-28222000
CY2021	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	1820000
CY2020	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	22859000
CY2019	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	38152000
CY2021	us-gaap	Increase Decrease In Derivative Assets And Liabilities IncreaseDecreaseInDerivativeAssetsAndLiabilities	3553000
CY2020	us-gaap	Increase Decrease In Derivative Assets And Liabilities IncreaseDecreaseInDerivativeAssetsAndLiabilities	1045000
CY2019	us-gaap	Increase Decrease In Derivative Assets And Liabilities IncreaseDecreaseInDerivativeAssetsAndLiabilities	-10117000
CY2021	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	-13697000
CY2020	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	-1787000
CY2019	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	-2623000
CY2021	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	4571000
CY2020	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	588000
CY2019	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	-209000
CY2021	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	23701000
CY2020	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-41333000
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-21416000
CY2021	us-gaap	Payments To Acquire Royalty Interests In Mining Properties PaymentsToAcquireRoyaltyInterestsInMiningProperties	1186000
CY2020	us-gaap	Payments To Acquire Royalty Interests In Mining Properties PaymentsToAcquireRoyaltyInterestsInMiningProperties	1248000
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	238284000
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	61106000
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	419714000
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	245440000
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	285821000
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	266356000
CY2019	us-gaap	Payments To Acquire Royalty Interests In Mining Properties PaymentsToAcquireRoyaltyInterestsInMiningProperties	1249000
CY2021	aci	Proceeds From Payments For Disposals And Divestitures ProceedsFromPaymentsForDisposalsAndDivestitures	21228000
CY2020	aci	Proceeds From Payments For Disposals And Divestitures ProceedsFromPaymentsForDisposalsAndDivestitures	1007000
CY2019	aci	Proceeds From Payments For Disposals And Divestitures ProceedsFromPaymentsForDisposalsAndDivestitures	6135000
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	120624000
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	205216000
CY2021	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	87486000
CY2020	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	158708000
CY2019	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	233074000
CY2021	aci	Purchases Of Investments Advances To Affiliates PurchasesOfInvestmentsAdvancesToAffiliates	3303000
CY2020	aci	Purchases Of Investments Advances To Affiliates PurchasesOfInvestmentsAdvancesToAffiliates	1549000
CY2019	aci	Purchases Of Investments Advances To Affiliates PurchasesOfInvestmentsAdvancesToAffiliates	5499000
CY2020	us-gaap	Proceeds From Insurance Settlement Investing Activities ProceedsFromInsuranceSettlementInvestingActivities	23518000
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-141215000
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-226009000
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-239111000
CY2021	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	7895000
CY2020	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	3000000
CY2019	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	3000000
CY2021	aci	Proceeds From Equipment Financing ProceedsFromEquipmentFinancing	19438000
CY2020	aci	Proceeds From Equipment Financing ProceedsFromEquipmentFinancing	53611000
CY2021	us-gaap	Proceeds From Issuance Of Debt ProceedsFromIssuanceOfDebt	44985000
CY2020	us-gaap	Proceeds From Issuance Of Debt ProceedsFromIssuanceOfDebt	53090000
CY2020	us-gaap	Proceeds From Convertible Debt ProceedsFromConvertibleDebt	155250000
CY2020	aci	Payments To Acquire Capped Call Transactions PaymentsToAcquireCappedCallTransactions	17543000
CY2021	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	11195000
CY2020	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	15922000
CY2019	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	5373000
CY2021	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	2057000
CY2020	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	9718000
CY2021	us-gaap	Payments Of Ordinary Dividends PaymentsOfOrdinaryDividends	3830000
CY2020	us-gaap	Payments Of Ordinary Dividends PaymentsOfOrdinaryDividends	8245000
CY2019	us-gaap	Payments Of Ordinary Dividends PaymentsOfOrdinaryDividends	30220000
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	244998000
CY2021	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	4840000
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	2195000
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	8961000
CY2021	us-gaap	Proceeds From Warrant Exercises ProceedsFromWarrantExercises	1175000
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	32000
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	35781000
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	205328000
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-292520000
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	132850000
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	40425000
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-111917000
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	193445000
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	153020000
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	264937000
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	326295000
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	193445000
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	153020000
CY2021	us-gaap	Interest Paid Net InterestPaidNet	31568000
CY2020	us-gaap	Interest Paid Net InterestPaidNet	19602000
CY2019	us-gaap	Interest Paid Net InterestPaidNet	16627000
CY2021Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	1101000
CY2020Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	5953000
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	37535000
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	52272000
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	704821000
CY2019	us-gaap	Dividends Dividends	30040000
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	21989000
CY2019	us-gaap	Stock Issued During Period Shares Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures	172720
CY2019	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2000
CY2019	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	8962000
CY2019	us-gaap	Adjustments To Additional Paid In Capital Warrant Issued AdjustmentsToAdditionalPaidInCapitalWarrantIssued	32000
CY2019	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	2872548
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	243498000
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	196192000
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	640536000
CY2020	us-gaap	Dividends Dividends	7904000
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	17435000
CY2020	us-gaap	Adjustments To Additional Paid In Capital Equity Component Of Convertible Debt AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt	39237000
CY2020	aci	Purchase Of Capped Call Related To Convertible Debt PurchaseOfCappedCallRelatedToConvertibleDebt	17543000
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	2195000
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-386005000
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	283561000
CY2021	us-gaap	Dividends Dividends	4001000
CY2021	us-gaap	Stock Issued During Period Shares Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures	157609
CY2021	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2000
CY2021	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	20539000
CY2021	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	4842000
CY2021	us-gaap	Adjustments To Additional Paid In Capital Warrant Issued AdjustmentsToAdditionalPaidInCapitalWarrantIssued	1175000
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	387432000
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	683866000
CY2021	us-gaap	Use Of Estimates UseOfEstimates	<p style="font-family:'Times New Roman','Times','serif';font-size:10pt;font-style:italic;font-weight:bold;margin:0pt 0pt 12pt 0pt;">Accounting Estimates</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-indent:18pt;margin:0pt 0pt 12pt 0pt;">The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and revenues and expenses in the accompanying consolidated financial statements and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates.</p>
CY2021Q4	aci	Restricted Cash Current Customer Deposits RestrictedCashCurrentCustomerDeposits	1100000
CY2020Q4	aci	Restricted Cash Held In Trust Tax Exempt Bond RestrictedCashHeldInTrustTaxExemptBond	6000000.0
CY2021	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	18600000
CY2020	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	11900000
CY2021Q4	us-gaap	Mineral Rights MineralRights	259800000
CY2020Q4	us-gaap	Mineral Rights MineralRights	290300000
CY2021Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	1200000
CY2021Q4	us-gaap	Deferred Finance Costs Current Net DeferredFinanceCostsCurrentNet	700000
CY2020Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	1900000
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CY2021	us-gaap	Severance Costs1 SeveranceCosts1	0
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CY2020Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	846000
CY2021	aci	Change In Fair Value Of Coal Derivatives And Coal Trading Activities Net ChangeInFairValueOfCoalDerivativesAndCoalTradingActivitiesNet	-2392000
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CY2021Q4	us-gaap	Long Term Debt LongTermDebt	560673000
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CY2021Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	0
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CY2021Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	605061000
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CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	1525000
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CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	16490000
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CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1874000
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CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	504392000
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	573995000
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CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	14319000
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CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	48116000
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CY2021	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	3830000
CY2020Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.50
CY2020Q1	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	8245000
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	8245000
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CY2019Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	1050000000
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	10088378
CY2021	aci	Class Of Warrant Or Right Exercised ClassOfWarrantOrRightExercised	20145
CY2021Q4	us-gaap	Class Of Warrant Or Right Outstanding ClassOfWarrantOrRightOutstanding	1825423
CY2021Q4	aci	Warrant Or Right Repurchase Per Share Amount WarrantOrRightRepurchasePerShareAmount	0
CY2021Q4	aci	Warrant Or Right Percentage Of Common Stock Benchmark For Consideration WarrantOrRightPercentageOfCommonStockBenchmarkForConsideration	0.90
CY2021	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	4439000
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CY2021Q4	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	223000000
CY2021Q4	aci	Warrant Or Right Percentage Of Common Stock Benchmark For Consideration WarrantOrRightPercentageOfCommonStockBenchmarkForConsideration	0.90
CY2020Q1	aci	Additional Collateral Contingent Amount Self Insured AdditionalCollateralContingentAmountSelfInsured	71100000
CY2020Q1	aci	Threshold For Number Of Days To Post Additional Collateral ThresholdForNumberOfDaysToPostAdditionalCollateral	P30D
CY2021	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	7796000
CY2020	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	7564000
CY2019	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	6677000
CY2020	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	5115000
CY2019	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	4922000
CY2021	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	2363000
CY2020	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	1189000
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CY2021	aci	Increase Decrease Workers Compensation Obligations Change In Discount Rate IncreaseDecreaseWorkersCompensationObligationsChangeInDiscountRate	11600000
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CY2021Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	238307000
CY2020Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	259954000
CY2021Q4	us-gaap	Workers Compensation Liability Current WorkersCompensationLiabilityCurrent	14202000
CY2020Q4	us-gaap	Workers Compensation Liability Current WorkersCompensationLiabilityCurrent	15259000
CY2021Q4	us-gaap	Workers Compensation Liability Noncurrent WorkersCompensationLiabilityNoncurrent	224105000
CY2020Q4	us-gaap	Workers Compensation Liability Noncurrent WorkersCompensationLiabilityNoncurrent	244695000
CY2021Q4	us-gaap	Liability For Future Policy Benefits Disability And Accident Benefits LiabilityForFuturePolicyBenefitsDisabilityAndAccidentBenefits	13100000
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CY2021Q4	us-gaap	Defined Benefit Plan Health Care Cost Trend Rate Assumed Next Fiscal Year DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear	0.080
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CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.064
CY2021	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	215000
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15318000
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15153000
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16218000
CY2021	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	2261000
CY2019	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	1080000
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	17579000
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	15153000
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	17298000
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	14646000
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CY2021Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	4215000
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	5512000
CY2021Q4	aci	Lease Assets LeaseAssets	18861000
CY2020Q4	aci	Lease Assets LeaseAssets	22581000
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CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	2454000
CY2021Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	4097000
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CY2020Q4	aci	Lease Liabilities LeaseLiabilities	23606000
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CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P5Y11M26D
CY2021Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P3Y3M
CY2021Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	5014000
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	3364000
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	3620000
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	3377000
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	3610000
CY2021	aci	Finance Lease Cost FinanceLeaseCost	1572000
CY2020	aci	Finance Lease Cost FinanceLeaseCost	1179000
CY2021	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	1210000
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	909000
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	3389000
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	1210000
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	3356000
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	1210000
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	3200000
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	1210000
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	3185000
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CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	3080000
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	1533000
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	17743000
CY2021Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	5741000
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CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	15319000
CY2021	us-gaap	Operating Lease Expense OperatingLeaseExpense	9200000
CY2020	us-gaap	Operating Lease Expense OperatingLeaseExpense	8600000
CY2019	us-gaap	Operating Lease Expense OperatingLeaseExpense	12000000.0
CY2021	us-gaap	Royalty Expense RoyaltyExpense	127800000
CY2020	us-gaap	Royalty Expense RoyaltyExpense	103700000
CY2019	us-gaap	Royalty Expense RoyaltyExpense	149500000
CY2021Q4	aci	Surety Bonds Outstanding SuretyBondsOutstanding	26000000.0
CY2021	aci	Goods Sold During Year GoodsSoldDuringYear	73000000.0
CY2021	aci	Percentage Of Goods Sold Under Long Term Contract PercentageOfGoodsSoldUnderLongTermContract	0.63
CY2021	aci	Percentage Company Revenue PercentageCompanyRevenue	0.35
CY2021	aci	Long Term Contracts Life Term Maximum LongTermContractsLifeTermMaximum	P5Y
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2208042000
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1467592000
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2294352000
CY2021Q4	us-gaap	Litigation Reserve LitigationReserve	100000
CY2020Q4	us-gaap	Litigation Reserve LitigationReserve	100000
CY2021Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On First Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary	132700000
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3
CY2021	aci	Number Of Remaining Active Thermal Mines NumberOfRemainingActiveThermalMines	3
CY2021	aci	Number Of Distinct Lines Of Business NumberOfDistinctLinesOfBusiness	2
CY2021	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2
CY2021	aci	Number Of Remaining Active Thermal Mines NumberOfRemainingActiveThermalMines	3
CY2021	aci	Number Of Distinct Lines Of Business NumberOfDistinctLinesOfBusiness	2
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2208042000
CY2021	aci	Adjusted Ebitda AdjustedEBITDA	533430000
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	120327000
CY2021	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	21748000
CY2020	aci	Adjusted Ebitda AdjustedEBITDA	23743000
CY2021Q4	us-gaap	Assets Assets	2117160000
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	245440000
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1467592000
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	121552000
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	19887000
CY2020Q4	us-gaap	Assets Assets	1722472000
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	285821000
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2294352000
CY2019	aci	Adjusted Ebitda AdjustedEBITDA	363167000
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	111621000
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	20548000
CY2019Q4	us-gaap	Assets Assets	1867756000
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	266356000
CY2021	us-gaap	Net Income Loss NetIncomeLoss	337573000
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-344615000
CY2019	us-gaap	Net Income Loss NetIncomeLoss	233799000
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1874000
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-7000
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	248000
CY2021	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-23344000
CY2020	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-10624000
CY2019	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-6794000
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	120327000
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	121552000
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	111621000
CY2021	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	21748000
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	19887000
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	20548000
CY2020	aci	Operating Income Expense Related To Joint Venture OperatingIncomeExpenseRelatedToJointVenture	16087000
CY2019	aci	Operating Income Expense Related To Joint Venture OperatingIncomeExpenseRelatedToJointVenture	13816000
CY2020	aci	Asset Impairment Charges And Mine Closure Costs AssetImpairmentChargesAndMineClosureCosts	221380000
CY2020	us-gaap	Gain On Business Interruption Insurance Recovery GainOnBusinessInterruptionInsuranceRecovery	23518000
CY2019	us-gaap	Gain Loss Related To Litigation Settlement GainLossRelatedToLitigationSettlement	39000000
CY2021	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	4339000
CY2020	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	3884000
CY2019	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	2053000
CY2020	us-gaap	Nondebtor Reorganization Items Net Gain Loss On Settlement Of Other Claims1 NondebtorReorganizationItemsNetGainLossOnSettlementOfOtherClaims1	26000
CY2019	us-gaap	Nondebtor Reorganization Items Net Gain Loss On Settlement Of Other Claims1 NondebtorReorganizationItemsNetGainLossOnSettlementOfOtherClaims1	24000
CY2021	aci	Adjusted Ebitda AdjustedEBITDA	533430000
CY2020	aci	Adjusted Ebitda AdjustedEBITDA	23743000
CY2019	aci	Adjusted Ebitda AdjustedEBITDA	363167000
CY2021	aci	Ebitd From Idled Or Otherwise Disposed Operations EBITDFromIdledOrOtherwiseDisposedOperations	2469000
CY2020	aci	Ebitd From Idled Or Otherwise Disposed Operations EBITDFromIdledOrOtherwiseDisposedOperations	15858000
CY2019	aci	Ebitd From Idled Or Otherwise Disposed Operations EBITDFromIdledOrOtherwiseDisposedOperations	12926000
CY2021	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	92342000
CY2020	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	82397000
CY2019	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	95781000
CY2021	aci	Other Income Expense OtherIncomeExpense	-9702000
CY2020	aci	Other Income Expense OtherIncomeExpense	3359000
CY2019	aci	Other Income Expense OtherIncomeExpense	-14488000
CY2021	aci	Segment Adjusted Ebitd From Coal Operations SegmentAdjustedEBITDFromCoalOperations	618539000
CY2020	aci	Segment Adjusted Ebitd From Coal Operations SegmentAdjustedEBITDFromCoalOperations	125357000
CY2019	aci	Segment Adjusted Ebitd From Coal Operations SegmentAdjustedEBITDFromCoalOperations	457386000

Files In Submission

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$ARCH
ARCH RESOURCES, INC. Stock $arch

2021 Q4 Form 10-K Financial Statement

#000155837022001243 Filed on February 16, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ARCH ARCH RESOURCES, INC. Stock $arch

2021 Q4 Form 10-K Financial Statement

#000155837022001243 Filed on February 16, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ARCH
ARCH RESOURCES, INC. Stock $arch