$AMR
Alpha Metallurgical Resources, Inc. Stock $amr

$amr Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000170471521000026 Filed on March 15, 2021

Income Statement

Concept	2019 Q4	2019 Q1	2019
Revenue	$499.1M	$609.1M	$2.001B
YoY Change	-12.76%	26.29%	-1.47%
Cost Of Revenue	$187.7M	$515.7M	$1.668B
YoY Change	-58.86%	38.18%	0.4%
Gross Profit	$22.40M	$93.40M	$333.5M
YoY Change	-80.66%	-14.39%	-9.89%
Gross Profit Margin	4.49%	15.33%	16.66%
Selling, General & Admin	$25.80M	$20.95M	$78.95M
YoY Change	63.29%	9.36%	33.21%
% of Gross Profit	115.18%	22.43%	23.67%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	-$15.60M	$61.30M	$315.2M
YoY Change	-135.86%	181.19%	306.71%
% of Gross Profit	-69.64%	65.63%	94.51%
Operating Expenses	$68.40M	$20.95M	$78.95M
YoY Change	96.55%	9.36%	33.21%
Operating Profit	-$46.00M	$17.78M	-$169.1M
YoY Change	-156.79%	-73.78%	-187.27%
Interest Expense	-$17.80M	$15.16M	$67.52M
YoY Change	23.61%	64.64%	73.98%
% of Operating Profit		85.23%
Other Income/Expense, Net	-$7.300M	-$14.57M	-$103.8M
YoY Change	1360.0%	54.17%	84.47%
Pretax Income	-$252.8M	$3.212M	-$272.9M
YoY Change	2533.33%	-94.5%	-298.49%
Income Tax	-$44.40M	-$4.778M	-$53.29M
% Of Pretax Income		-148.75%
Net Earnings	-$140.9M	$6.815M	-$316.3M
YoY Change	-190.03%	-88.03%	-205.73%
Net Earnings / Revenue	-28.24%	1.12%	-15.81%
Basic Earnings Per Share	-$7.75	$0.36	-$16.82
Diluted Earnings Per Share	-$7.75	$0.35	-$16.82
COMMON SHARES
Basic Shares Outstanding	18.20M shares	18.89M shares	18.81M shares
Diluted Shares Outstanding	18.20M shares	19.54M shares	18.81M shares

Balance Sheet

Concept	2019 Q4	2019 Q1	2019
SHORT-TERM ASSETS
Cash & Short-Term Investments	$212.8M	$182.0M	$212.8M
YoY Change	-8.9%	152.43%	-8.9%
Cash & Equivalents	$212.8M	$182.0M	$212.8M
Short-Term Investments
Other Short-Term Assets	$91.40M	$173.7M	$48.50M
YoY Change	-49.61%	46.71%	-54.63%
Inventory	$150.9M	$145.1M	$162.7M
Prepaid Expenses
Receivables	$224.2M	$319.7M	$244.7M
Other Receivables	$8.447M	$0.00	$42.80M
Total Short-Term Assets	$711.5M	$820.4M	$711.5M
YoY Change	-14.24%	59.43%	-14.24%
LONG-TERM ASSETS
Property, Plant & Equipment	$583.3M	$678.5M	$1.115B
YoY Change	-16.68%	242.53%	-9.21%
Goodwill	$0.00	$107.5M
YoY Change	-100.0%
Intangibles	$124.2M	$147.9M
YoY Change	-19.63%
Long-Term Investments	$18.41M		$18.40M
YoY Change	20.85%
Other Assets	$189.5M	$188.2M	$268.5M
YoY Change	3.16%	15.34%	-38.7%
Total Long-Term Assets	$1.591B	$1.936B	$1.591B
YoY Change	-16.96%	423.85%	-16.97%
TOTAL ASSETS
Total Short-Term Assets	$711.5M	$820.4M	$711.5M
Total Long-Term Assets	$1.591B	$1.936B	$1.591B
Total Assets	$2.303B	$2.756B	$2.303B
YoY Change	-16.14%	211.74%	-16.14%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$82.73M	$109.9M	$98.70M
YoY Change	-27.79%	27.0%	-13.87%
Accrued Expenses	$139.5M	$150.8M	$93.90M
YoY Change	-6.2%	145.62%	-8.48%
Deferred Revenue	$0.00
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$28.50M	$43.10M	$28.50M
YoY Change	-33.26%	314.42%	-33.26%
Total Short-Term Liabilities	$315.2M	$355.2M	$315.2M
YoY Change	-11.28%	53.03%	-11.26%
LONG-TERM LIABILITIES
Long-Term Debt	$564.5M	$540.4M	$564.5M
YoY Change	3.52%	49.49%	3.52%
Other Long-Term Liabilities	$26.82M	$39.13M	$726.6M
YoY Change	-48.83%	-72.29%	-4.31%
Total Long-Term Liabilities	$26.82M	$39.13M	$1.291B
YoY Change	-48.83%	-92.22%	-1.03%
TOTAL LIABILITIES
Total Short-Term Liabilities	$315.2M	$355.2M	$315.2M
Total Long-Term Liabilities	$26.82M	$39.13M	$1.291B
Total Liabilities	$1.607B	$1.675B	$1.607B
YoY Change	-4.07%	128.01%	-4.07%
SHAREHOLDERS EQUITY
Retained Earnings	$86.81M	$409.9M
YoY Change	-78.47%
Common Stock	$205.0K	$203.0K
YoY Change	1.49%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$108.0M	$74.53M
YoY Change	53.47%
Treasury Stock Shares
Shareholders Equity	$696.1M	$1.081B	$696.1M
YoY Change
Total Liabilities & Shareholders Equity	$2.303B	$2.756B	$2.303B
YoY Change	-16.14%	211.74%	-16.14%

Cashflow Statement

Concept	2019 Q4	2019 Q1	2019
OPERATING ACTIVITIES
Net Income	-$140.9M	$6.815M	-$316.3M
YoY Change	-190.03%	-88.03%	-205.73%
Depreciation, Depletion And Amortization	-$15.60M	$61.30M	$315.2M
YoY Change	-135.86%	181.19%	306.71%
Cash From Operating Activities	-$5.700M	$14.61M	$131.9M
YoY Change	-68.16%	-148.17%	-16.73%
INVESTING ACTIVITIES
Capital Expenditures	-$48.20M	-$41.10M	-$192.4M
YoY Change	91.27%	111.86%	134.92%
Acquisitions
YoY Change
Other Investing Activities	$24.10M	-$403.0K	-$535.0K
YoY Change	-87.88%	632.73%	-17933.33%
Cash From Investing Activities	-$24.20M	-$45.32M	-$191.8M
YoY Change	-113.93%	44.58%	-287.63%
FINANCING ACTIVITIES
Cash Dividend Paid			$0.00
YoY Change
Common Stock Issuance & Retirement, Net		$4.171M	$37.62M
YoY Change		-13.73%	85.6%
Debt Paid & Issued, Net		$6.875M	$552.8M
YoY Change		587.5%	17.19%
Cash From Financing Activities	-5.600M	-$11.79M	-$69.69M
YoY Change	-114.89%	86.81%	-406.9%
NET CHANGE
Cash From Operating Activities	-5.700M	$14.61M	$131.9M
Cash From Investing Activities	-24.20M	-$45.32M	-$191.8M
Cash From Financing Activities	-5.600M	-$11.79M	-$69.69M
Net Change In Cash	-35.50M	-$42.50M	-$129.6M
YoY Change	-118.36%	-37.5%	-145.74%
FREE CASH FLOW
Cash From Operating Activities	-$5.700M	$14.61M	$131.9M
Capital Expenditures	-$48.20M	-$41.10M	-$192.4M
Free Cash Flow	$42.50M	$55.71M	$324.3M
YoY Change	482.19%	-609.47%	34.96%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0001704715
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2021Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	18389139	shares
CY2020Q2	dei	Entity Public Float EntityPublicFloat	56000000	USD
CY2020	us-gaap	Accounting Standards Update Extensible List AccountingStandardsUpdateExtensibleList	us-gaap:AccountingStandardsUpdate201613Member
CY2019Q1	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:OtherLiabilitiesNoncurrent
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CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:LongTermDebtAndCapitalLeaseObligations
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:LongTermDebtAndCapitalLeaseObligations
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CY2020Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:OtherLiabilitiesNoncurrent
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P1Y11M9D
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P2Y9M21D
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P8Y5M12D
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CY2019Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	ctra:AccruedLiabilitiesAndOtherLiabilitiesCurrent
CY2020Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	ctra:AccruedLiabilitiesAndOtherLiabilitiesCurrent
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-38735
CY2020	dei	Entity Registrant Name EntityRegistrantName	ALPHA METALLURGICAL RESOURCES, INC.
CY2020	dei	Entity Registrant Name EntityRegistrantName	ALPHA METALLURGICAL RESOURCES, INC.
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	81-3015061
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	340 Martin Luther King Jr. Blvd.
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Bristol
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	TN
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	37620
CY2020	dei	City Area Code CityAreaCode	423
CY2020	dei	Local Phone Number LocalPhoneNumber	573-0300
CY2020	dei	Security12b Title Security12bTitle	Common Stock, par value $0.01 per share
CY2020	dei	Trading Symbol TradingSymbol	AMR
CY2020	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	No
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Non-accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	true
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Entity Shell Company EntityShellCompany	false
CY2020Q2	dei	Entity Public Float EntityPublicFloat	56000000	USD
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CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1413124000	USD
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CY2020	us-gaap	Other Income OtherIncome	3063000	USD
CY2019	us-gaap	Other Income OtherIncome	5346000	USD
CY2020	us-gaap	Revenues Revenues	1416187000	USD
CY2019	us-gaap	Revenues Revenues	2001280000	USD
CY2020	us-gaap	Cost Of Goods And Service Excluding Depreciation Depletion And Amortization CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization	1281011000	USD
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CY2020	amr	Depreciation Depletion And Amortization Excluding Acquired Intangibles DepreciationDepletionAndAmortizationExcludingAcquiredIntangibles	139885000	USD
CY2019	amr	Depreciation Depletion And Amortization Excluding Acquired Intangibles DepreciationDepletionAndAmortizationExcludingAcquiredIntangibles	215757000	USD
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CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	9214000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	-3189000	USD
CY2020	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	57356000	USD
CY2019	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	78953000	USD
CY2020	amr	Business Acquisition Integrationand Other Related Costs BusinessAcquisitionIntegrationandOtherRelatedCosts	0	USD
CY2019	amr	Business Acquisition Integrationand Other Related Costs BusinessAcquisitionIntegrationandOtherRelatedCosts	1090000	USD
CY2020	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	83878000	USD
CY2019	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	66324000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
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CY2020	us-gaap	Costs And Expenses CostsAndExpenses	1586875000	USD
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CY2020	us-gaap	Interest Expense InterestExpense	74528000	USD
CY2019	us-gaap	Interest Expense InterestExpense	67521000	USD
CY2020	us-gaap	Investment Income Interest InvestmentIncomeInterest	7027000	USD
CY2019	us-gaap	Investment Income Interest InvestmentIncomeInterest	7247000	USD
CY2020	amr	Gain Losson Extinguishmentand Modificationof Debt GainLossonExtinguishmentandModificationofDebt	0	USD
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CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-6874000	USD
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CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-7278000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-7405000	USD
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CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-351805000	USD
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CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	363620000	USD
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CY2019Q4	us-gaap	Mineral Properties Accumulated Depletion MineralPropertiesAccumulatedDepletion	27548000	USD
CY2020Q4	us-gaap	Mineral Rights MineralRights	463250000	USD
CY2019Q4	us-gaap	Mineral Rights MineralRights	523012000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	25700000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	26806000	USD
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CY2019Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	122524000	USD
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CY2019Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	33065000	USD
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CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	20600000	shares
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CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	20500000	shares
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CY2019Q4	us-gaap	Common Stock Value CommonStockValue	205000	USD
CY2020Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	779424000	USD
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CY2020Q4	us-gaap	Treasury Stock Common Shares TreasuryStockCommonShares	2300000	shares
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CY2019Q4	us-gaap	Treasury Stock Value TreasuryStockValue	107984000	USD
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CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	33123000	USD
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CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	124353000	USD
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CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	4896000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	12397000	USD
CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-3473000	USD
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CY2020	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-5972000	USD
CY2019	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-5204000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-91190000	USD
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CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-28148000	USD
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CY2019	amr	Increase Decreasein Acquisition Related Obligations IncreaseDecreaseinAcquisitionRelatedObligations	28128000	USD
CY2020	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	-19375000	USD
CY2019	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	-111616000	USD
CY2020	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-43831000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-33557000	USD
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CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	131880000	USD
CY2020	amr	Paymentsto Acquire Productive Assets Including Discontinued Operations PaymentstoAcquireProductiveAssetsIncludingDiscontinuedOperations	153990000	USD
CY2019	amr	Paymentsto Acquire Productive Assets Including Discontinued Operations PaymentstoAcquireProductiveAssetsIncludingDiscontinuedOperations	192411000	USD
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CY2019	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	2780000	USD
CY2020	amr	Cash Paid On Sale Of Business CashPaidOnSaleOfBusiness	52192000	USD
CY2019	amr	Cash Paid On Sale Of Business CashPaidOnSaleOfBusiness	0	USD
CY2020	amr	Payments To Acquire Equity Method Investments Capital Contributions PaymentsToAcquireEquityMethodInvestmentsCapitalContributions	3443000	USD
CY2019	amr	Payments To Acquire Equity Method Investments Capital Contributions PaymentsToAcquireEquityMethodInvestmentsCapitalContributions	10051000	USD
CY2020	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	21129000	USD
CY2019	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	92855000	USD
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CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-191752000	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	57500000	USD
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CY2019	amr	Finance Lease Principal Payments Including Discontinued Operations FinanceLeasePrincipalPaymentsIncludingDiscontinuedOperations	3654000	USD
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CY2019	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	6689000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	209000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	37622000	USD
CY2020	us-gaap	Repayments Of Notes Payable RepaymentsOfNotesPayable	16723000	USD
CY2019	us-gaap	Repayments Of Notes Payable RepaymentsOfNotesPayable	14818000	USD
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CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	952000	USD
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CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-69694000	USD
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CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	477246000	USD
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CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	347680000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	49294000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	51877000	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	5000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	3039000	USD
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CY2020	us-gaap	Capital Lease Obligations Incurred CapitalLeaseObligationsIncurred	4411000	USD
CY2019	us-gaap	Capital Lease Obligations Incurred CapitalLeaseObligationsIncurred	5324000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	7493000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	4110000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value Including Discontinued Operations CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	139227000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value Including Discontinued Operations CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	212793000	USD
CY2020Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	9311000	USD
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CY2020Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	96033000	USD
CY2019Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	122524000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	244571000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	347680000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1071140000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	-316319000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-35486000	USD
CY2019	amr	Stock Issued During Period Value Sharebased Compensation Including Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period StockIssuedDuringPeriodValueSharebasedCompensationIncludingAdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriod	13456000	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	934000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	37622000	USD
CY2019	amr	Stock Issued During Period Value Warrants Exercised StockIssuedDuringPeriodValueWarrantsExercised	19000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	696122000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-446899000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-53369000	USD
CY2020	amr	Stock Issued During Period Value Sharebased Compensation Including Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period StockIssuedDuringPeriodValueSharebasedCompensationIncludingAdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriod	3718000	USD
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	970000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	200102000	USD
CY2020Q4	amr	Alternative Minimum Tax Tax Credit Cash Received Cares Act AlternativeMinimumTaxTaxCreditCashReceivedCARESAct	66130000	USD
CY2020Q4	amr	Accrued Payroll Taxes Cares Act AccruedPayrollTaxesCARESAct	15109000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:115%">Use of Estimates</span></div><div><span><br/></span></div><div style="text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of the Company’s Consolidated Financial Statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include inventories; mineral reserves; asset impairments; goodwill impairment; reclamation obligations; post-employment and other employee benefit obligations; useful lives, depletion and amortization; reserves for workers’ compensation and black lung claims; deferred income taxes; income taxes refundable and receivable; reserves for contingencies and litigation; fair value of financial instruments; and fair value adjustments for acquisition accounting. Estimates are based on facts and circumstances believed to be reasonable at the time; however, actual results could differ from those estimates.</span></div>
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	139227000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	212803000	USD
CY2020Q4	us-gaap	Mineral Rights MineralRights	463250000	USD
CY2019Q4	us-gaap	Mineral Rights MineralRights	523012000	USD
CY2020Q4	amr	Asset Retirement Obligation Assets AssetRetirementObligationAssets	10491000	USD
CY2019Q4	amr	Asset Retirement Obligation Assets AssetRetirementObligationAssets	36723000	USD
CY2020	us-gaap	Depletion Depletion	-13746000	USD
CY2019	us-gaap	Depletion Depletion	14551000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	88196000	USD
CY2020Q4	amr	Finite Lived Intangible Liabilities Gross FiniteLivedIntangibleLiabilitiesGross	327000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	87869000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	124246000	USD
CY2019Q4	amr	Finite Lived Intangible Liabilities Gross FiniteLivedIntangibleLiabilitiesGross	6018000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	118228000	USD
CY2020Q4	amr	Finite Lived Intangibles Amortization Expense Revenue Year One FiniteLivedIntangiblesAmortizationExpenseRevenueYearOne	9712000	USD
CY2020Q4	amr	Finite Lived Intangibles Amortization Expense Revenue Year Two FiniteLivedIntangiblesAmortizationExpenseRevenueYearTwo	10039000	USD
CY2020Q4	amr	Finite Lived Intangibles Amortization Expense Revenue Year Three FiniteLivedIntangiblesAmortizationExpenseRevenueYearThree	10028000	USD
CY2020Q4	amr	Finite Lived Intangibles Amortization Expense Revenue Year Four FiniteLivedIntangiblesAmortizationExpenseRevenueYearFour	8677000	USD
CY2020Q4	amr	Finite Lived Intangibles Amortization Expense Revenue Year Five FiniteLivedIntangiblesAmortizationExpenseRevenueYearFive	8672000	USD
CY2020Q4	amr	Finite Lived Intangibles Amortization Expense Revenueafter Year Five FiniteLivedIntangiblesAmortizationExpenseRevenueafterYearFive	40741000	USD
CY2020Q4	amr	Finite Lived Intangibles FiniteLivedIntangibles	87869000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	124353000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	95624000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	124353000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	0	USD
CY2020Q4	us-gaap	Workers Compensation Discount Amount WorkersCompensationDiscountAmount	24061000	USD
CY2019Q4	us-gaap	Workers Compensation Discount Amount WorkersCompensationDiscountAmount	24680000	USD
CY2016Q3	us-gaap	Class Of Warrant Or Right Outstanding ClassOfWarrantOrRightOutstanding	810811	shares
CY2016Q3	us-gaap	Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1 ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1	55.93
CY2016Q3	us-gaap	Class Of Warrant Or Right Number Of Securities Called By Each Warrant Or Right ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight	1	shares
CY2016Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2019Q4	us-gaap	Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1 ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1	46.911
CY2020Q4	us-gaap	Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1 ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1	46.911
CY2020Q4	us-gaap	Class Of Warrant Or Right Number Of Securities Called By Each Warrant Or Right ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight	1.15	shares
CY2019Q4	us-gaap	Class Of Warrant Or Right Number Of Securities Called By Each Warrant Or Right ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight	1.15	shares
CY2016Q3	us-gaap	Class Of Warrant Or Right Outstanding ClassOfWarrantOrRightOutstanding	810811	shares
CY2019Q4	us-gaap	Class Of Warrant Or Right Outstanding ClassOfWarrantOrRightOutstanding	801370	shares
CY2020Q4	us-gaap	Class Of Warrant Or Right Outstanding ClassOfWarrantOrRightOutstanding	801370	shares
CY2019Q4	us-gaap	Class Of Warrant Or Right Number Of Securities Called By Warrants Or Rights ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights	921576	shares
CY2020Q4	us-gaap	Class Of Warrant Or Right Number Of Securities Called By Warrants Or Rights ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights	921576	shares
CY2019	us-gaap	Stock Issued During Period Shares Conversion Of Convertible Securities StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities	414	shares
CY2019	amr	Shares Withheld Upon Conversionof Convertible Securities SharesWithheldUponConversionofConvertibleSecurities	5	shares
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	18383000	USD
CY2019Q4	us-gaap	Equity Method Investments EquityMethodInvestments	18413000	USD
CY2018Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	0	USD
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	10136000	USD
CY2019	us-gaap	Disposal Group Including Discontinued Operation Depreciation And Amortization DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization	145913000	USD
CY2018Q4	amr	Capital Lease Assets CapitalLeaseAssets	9786000	USD
CY2019Q1	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	9786000	USD
CY2018Q4	amr	Capital Lease Assets CapitalLeaseAssets	9786000	USD
CY2019Q1	amr	Lease Rightof Use Asset LeaseRightofUseAsset	19922000	USD
CY2018Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	0	USD
CY2019Q1	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	3232000	USD
CY2018Q4	us-gaap	Capital Lease Obligations Current CapitalLeaseObligationsCurrent	2110000	USD
CY2019Q1	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	2110000	USD
CY2018Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	0	USD
CY2019Q1	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	6904000	USD
CY2018Q4	us-gaap	Capital Lease Obligations Noncurrent CapitalLeaseObligationsNoncurrent	4313000	USD
CY2019Q1	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	4313000	USD
CY2018Q4	us-gaap	Capital Lease Obligations CapitalLeaseObligations	6423000	USD
CY2019Q1	amr	Lease Liability LeaseLiability	16559000	USD
CY2019	us-gaap	Disposal Group Including Discontinued Operation Depreciation And Amortization DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization	145913000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	0	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	141676000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1413124000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1995934000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	113676000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	28000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	0	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	0	USD
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1317351	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	537918	shares
CY2020	amr	Weighted Average Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount WeightedAverageAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	142250	shares
CY2019	amr	Weighted Average Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount WeightedAverageAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	256668	shares
CY2020Q4	us-gaap	Inventory Net InventoryNet	108051000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	150888000	USD
CY2020	us-gaap	Inventory Write Down InventoryWriteDown	807000	USD
CY2020Q1	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	33709000	USD
CY2020Q2	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	17390000	USD
CY2020Q3	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	219000	USD
CY2020Q4	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	29636000	USD
CY2020	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	80954000	USD
CY2020Q1	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	0	USD
CY2020Q2	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	144348000	USD
CY2020Q3	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	3297000	USD
CY2020Q4	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	0	USD
CY2020	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	147645000	USD
CY2020Q1	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	33709000	USD
CY2020Q2	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	161738000	USD
CY2020Q3	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	3516000	USD
CY2020Q4	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	29636000	USD
CY2020	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	228599000	USD
CY2020Q1	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	33709000	USD
CY2020Q2	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	17390000	USD
CY2020Q3	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	219000	USD
CY2020Q4	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	29636000	USD
CY2020	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	80954000	USD
CY2020Q1	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	0	USD
CY2020Q2	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	144348000	USD
CY2020Q3	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	3297000	USD
CY2020Q4	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	0	USD
CY2020	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	147645000	USD
CY2020Q1	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	33709000	USD
CY2020Q2	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	161738000	USD
CY2020Q3	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	3516000	USD
CY2020Q4	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	29636000	USD
CY2020	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	228599000	USD
CY2019	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	60169000	USD
CY2019	amr	Impairmentof Prepaid Expensesand Other Assets ImpairmentofPrepaidExpensesandOtherAssets	6155000	USD
CY2019	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	17161000	USD
CY2020Q4	amr	Prepaid Freight PrepaidFreight	8515000	USD
CY2019Q4	amr	Prepaid Freight PrepaidFreight	8268000	USD
CY2020Q4	us-gaap	Other Receivables Net Current OtherReceivablesNetCurrent	13245000	USD
CY2019Q4	us-gaap	Other Receivables Net Current OtherReceivablesNetCurrent	8447000	USD
CY2020Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	9311000	USD
CY2019Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	12363000	USD
CY2020Q4	us-gaap	Deposits Assets Current DepositsAssetsCurrent	47000	USD
CY2019Q4	us-gaap	Deposits Assets Current DepositsAssetsCurrent	689000	USD
CY2020Q4	us-gaap	Prepaid Insurance PrepaidInsurance	6510000	USD
CY2019Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization	256378000	USD
CY2019Q4	us-gaap	Prepaid Insurance PrepaidInsurance	9591000	USD
CY2020Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	64565000	USD
CY2019Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	33915000	USD
CY2020Q4	amr	Prepaid Bond Premium PrepaidBondPremium	2576000	USD
CY2019Q4	amr	Prepaid Bond Premium PrepaidBondPremium	2454000	USD
CY2020Q4	us-gaap	Other Prepaid Expense Current OtherPrepaidExpenseCurrent	1483000	USD
CY2019Q4	us-gaap	Other Prepaid Expense Current OtherPrepaidExpenseCurrent	1996000	USD
CY2020Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	106252000	USD
CY2019Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	77723000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Before Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization	746043000	USD
CY2019Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Before Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization	692776000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization	382423000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	363620000	USD
CY2019Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	436398000	USD
CY2020	amr	Depreciation And Amortization Property Plant And Equipment And Non Mineral Asset Retirement Obligation Assets DepreciationAndAmortizationPropertyPlantAndEquipmentAndNonMineralAssetRetirementObligationAssets	153631000	USD
CY2019	amr	Depreciation And Amortization Property Plant And Equipment And Non Mineral Asset Retirement Obligation Assets DepreciationAndAmortizationPropertyPlantAndEquipmentAndNonMineralAssetRetirementObligationAssets	201206000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	5671000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	7298000	USD
CY2020Q4	us-gaap	Deposits Assets Noncurrent DepositsAssetsNoncurrent	28200000	USD
CY2019Q4	us-gaap	Deposits Assets Noncurrent DepositsAssetsNoncurrent	9621000	USD
CY2020Q4	us-gaap	Restricted Investments Noncurrent RestrictedInvestmentsNoncurrent	23768000	USD
CY2019Q4	us-gaap	Restricted Investments Noncurrent RestrictedInvestmentsNoncurrent	19399000	USD
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	18383000	USD
CY2019Q4	us-gaap	Equity Method Investments EquityMethodInvestments	18413000	USD
CY2020Q4	us-gaap	Income Taxes Receivable Noncurrent IncomeTaxesReceivableNoncurrent	0	USD
CY2019Q4	us-gaap	Income Taxes Receivable Noncurrent IncomeTaxesReceivableNoncurrent	64160000	USD
CY2020Q4	amr	Insurance Receivablefor Workers Compensation Noncurrent InsuranceReceivableforWorkersCompensationNoncurrent	48320000	USD
CY2019Q4	amr	Insurance Receivablefor Workers Compensation Noncurrent InsuranceReceivableforWorkersCompensationNoncurrent	52757000	USD
CY2020Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	25040000	USD
CY2019Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	17827000	USD
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	149382000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	189475000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	4262000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	9687000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	5671000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	7298000	USD
CY2020Q4	amr	Lease Rightof Use Asset LeaseRightofUseAsset	9933000	USD
CY2019Q4	amr	Lease Rightof Use Asset LeaseRightofUseAsset	16985000	USD
CY2020Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	2014000	USD
CY2019Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	3266000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	595000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	1402000	USD
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	1996000	USD
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	4651000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	5076000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	5896000	USD
CY2020Q4	amr	Lease Liability LeaseLiability	9681000	USD
CY2019Q4	amr	Lease Liability LeaseLiability	15215000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	3238000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	3738000	USD
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	358000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	477000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	2105000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	2389000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	1518000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	1851000	USD
CY2020	us-gaap	Lease Cost LeaseCost	7219000	USD
CY2019	us-gaap	Lease Cost LeaseCost	8455000	USD
CY2019	us-gaap	Sublease Income SubleaseIncome	0	USD
CY2020	us-gaap	Sublease Income SubleaseIncome	0	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	0	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	0	USD
CY2020	amr	Lease Payments LeasePayments	7157000	USD
CY2019	amr	Lease Payments LeasePayments	8349000	USD
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	358000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	463000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	3623000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	4240000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	3176000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	3646000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	221000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	1429000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	-12000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	371000	USD
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.061
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.054
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.115
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.114
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	2210000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	1210000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	1827000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	1076000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	269000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	1101000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	6000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	982000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	0	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	897000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	0	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	4018000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	4312000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	9284000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	302000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	3613000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	4010000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	5671000	USD
CY2020Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	40330000	USD
CY2019Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	37983000	USD
CY2020Q4	us-gaap	Workers Compensation Liability Current WorkersCompensationLiabilityCurrent	10355000	USD
CY2019Q4	us-gaap	Workers Compensation Liability Current WorkersCompensationLiabilityCurrent	11317000	USD
CY2020Q4	us-gaap	Accrual For Taxes Other Than Income Taxes Current AccrualForTaxesOtherThanIncomeTaxesCurrent	21540000	USD
CY2019Q4	us-gaap	Accrual For Taxes Other Than Income Taxes Current AccrualForTaxesOtherThanIncomeTaxesCurrent	24662000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	24990000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	38731000	USD
CY2020Q4	amr	Accrued Interest And Fees AccruedInterestAndFees	15902000	USD
CY2019Q4	amr	Accrued Interest And Fees AccruedInterestAndFees	4362000	USD
CY2020Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	13197000	USD
CY2019Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	0	USD
CY2020Q4	amr	Accrued Freight AccruedFreight	2610000	USD
CY2019Q4	amr	Accrued Freight AccruedFreight	5851000	USD
CY2020Q4	amr	Other Liabilities Miscellaneous Current OtherLiabilitiesMiscellaneousCurrent	4698000	USD
CY2019Q4	amr	Other Liabilities Miscellaneous Current OtherLiabilitiesMiscellaneousCurrent	9164000	USD
CY2020Q4	amr	Accrued Liabilitiesand Other Liabilities Current AccruedLiabilitiesandOtherLiabilitiesCurrent	140406000	USD
CY2019Q4	amr	Accrued Liabilitiesand Other Liabilities Current AccruedLiabilitiesandOtherLiabilitiesCurrent	139479000	USD
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet	17046000	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet	29695000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	582527000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	592934000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	28830000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	28476000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	553697000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	564458000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	28830000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	24815000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	9300000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	536628000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	599573000	USD
CY2020Q4	amr	Acquisition Related Obligations Discount Premium AcquisitionRelatedObligationsDiscountPremium	1491000	USD
CY2019Q4	amr	Acquisition Related Obligations Discount Premium AcquisitionRelatedObligationsDiscountPremium	4834000	USD
CY2020Q4	amr	Acquisition Related Obligations Carrying Amount AcquisitionRelatedObligationsCarryingAmount	39867000	USD
CY2019Q4	amr	Acquisition Related Obligations Carrying Amount AcquisitionRelatedObligationsCarryingAmount	79898000	USD
CY2020Q4	amr	Acquisition Related Obligations Carrying Amount Current AcquisitionRelatedObligationsCarryingAmountCurrent	19099000	USD
CY2019Q4	amr	Acquisition Related Obligations Carrying Amount Current AcquisitionRelatedObligationsCarryingAmountCurrent	33639000	USD
CY2020Q4	amr	Acquisition Related Obligations Carrying Amount Noncurrent AcquisitionRelatedObligationsCarryingAmountNoncurrent	20768000	USD
CY2019Q4	amr	Acquisition Related Obligations Carrying Amount Noncurrent AcquisitionRelatedObligationsCarryingAmountNoncurrent	46259000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	192038000	USD
CY2019	amr	Asset Retirement Obligation Measurement Period Adjustments AssetRetirementObligationMeasurementPeriodAdjustments	12718000	USD
CY2019	amr	Asset Retirement Obligation Accretion Expense Excluding Liabilities Heldfor Sale AssetRetirementObligationAccretionExpenseExcludingLiabilitiesHeldforSale	23852000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	5112000	USD
CY2019	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	-7162000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	23421000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	203137000	USD
CY2020	amr	Asset Retirement Obligation Accretion Expense Excluding Liabilities Heldfor Sale AssetRetirementObligationAccretionExpenseExcludingLiabilitiesHeldforSale	26504000	USD
CY2020	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	621000	USD
CY2020	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	-43765000	USD
CY2020	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	21433000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	165064000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	24990000	USD
CY2020Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	140074000	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	52427000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases	14710000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	-8750000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Transfers Net FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNet	0	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	28967000	USD
CY2018Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	59880000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases	9627000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	-3564000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Transfers Net FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNet	0	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	52427000	USD
CY2020	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	-35286000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-2164000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-53287000	USD
CY2020	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	0	USD
CY2019	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-8484000	USD
CY2020	us-gaap	Income Tax Expense Benefit Intraperiod Tax Allocation IncomeTaxExpenseBenefitIntraperiodTaxAllocation	-2164000	USD
CY2019	us-gaap	Income Tax Expense Benefit Intraperiod Tax Allocation IncomeTaxExpenseBenefitIntraperiodTaxAllocation	-61771000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-35187000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-45356000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-99000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1891000	USD
CY2019	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	-43465000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	33348000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-747000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-226000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-9075000	USD
CY2020	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	33122000	USD
CY2019	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	-9822000	USD
CY2020	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	-1839000	USD
CY2019	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	-46103000	USD
CY2020	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	-325000	USD
CY2019	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	-7184000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-2164000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-53287000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-51163000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-57310000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Depletion IncomeTaxReconciliationNondeductibleExpenseDepletion	-2039000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Depletion IncomeTaxReconciliationNondeductibleExpenseDepletion	-6270000	USD
CY2020	amr	Effective Income Tax Rate Reconciliation Sequestration Reduction Amount EffectiveIncomeTaxRateReconciliationSequestrationReductionAmount	-2123000	USD
CY2019	amr	Effective Income Tax Rate Reconciliation Sequestration Reduction Amount EffectiveIncomeTaxRateReconciliationSequestrationReductionAmount	0	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-9640000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-10255000	USD
CY2020	amr	Effective Income Tax Rate Reconciliation Changein Enacted State Tax Rate Amount EffectiveIncomeTaxRateReconciliationChangeinEnactedStateTaxRateAmount	-1235000	USD
CY2019	amr	Effective Income Tax Rate Reconciliation Changein Enacted State Tax Rate Amount EffectiveIncomeTaxRateReconciliationChangeinEnactedStateTaxRateAmount	-4172000	USD
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	59929000	USD
CY2019	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	10936000	USD
CY2020	amr	Effective Income Tax Rate Reconciliation Operating Loss Carryback Amount EffectiveIncomeTaxRateReconciliationOperatingLossCarrybackAmount	0	USD
CY2019	amr	Effective Income Tax Rate Reconciliation Operating Loss Carryback Amount EffectiveIncomeTaxRateReconciliationOperatingLossCarrybackAmount	14234000	USD
CY2020	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	0	USD
CY2019	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	919000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	0	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	26114000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	1739000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-1085000	USD
CY2020	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	2368000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	2070000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-2164000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-53287000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Asset Retirement Obligations DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAssetRetirementObligations	41268000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Asset Retirement Obligations DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAssetRetirementObligations	51114000	USD
CY2020Q4	amr	Deferred Tax Assets Tax Deferred Expense Reservesand Accruals Excluding Asset Retirement Obligations DeferredTaxAssetsTaxDeferredExpenseReservesandAccrualsExcludingAssetRetirementObligations	12131000	USD
CY2019Q4	amr	Deferred Tax Assets Tax Deferred Expense Reservesand Accruals Excluding Asset Retirement Obligations DeferredTaxAssetsTaxDeferredExpenseReservesandAccrualsExcludingAssetRetirementObligations	8265000	USD
CY2020Q4	amr	Deferred Tax Assets Tax Deferred Expense Workers Compensation Benefits Obligation DeferredTaxAssetsTaxDeferredExpenseWorkersCompensationBenefitsObligation	59478000	USD
CY2019Q4	amr	Deferred Tax Assets Tax Deferred Expense Workers Compensation Benefits Obligation DeferredTaxAssetsTaxDeferredExpenseWorkersCompensationBenefitsObligation	54128000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	52598000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	44413000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Equity Method Investments DeferredTaxAssetsEquityMethodInvestments	2050000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Equity Method Investments DeferredTaxAssetsEquityMethodInvestments	2509000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Alternative Minimum Tax DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Alternative Minimum Tax DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax	33065000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	255772000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	142510000	USD
CY2020Q4	amr	Deferred Tax Assets Tax Deferred Expense Reserveand Accruals Acquisition Related Obligations DeferredTaxAssetsTaxDeferredExpenseReserveandAccrualsAcquisitionRelatedObligations	10002000	USD
CY2019Q4	amr	Deferred Tax Assets Tax Deferred Expense Reserveand Accruals Acquisition Related Obligations DeferredTaxAssetsTaxDeferredExpenseReserveandAccrualsAcquisitionRelatedObligations	17902000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	10976000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	12299000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	444275000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	366205000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	263387000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	133020000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	180888000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	233185000	USD
CY2020Q4	amr	Deferred Tax Liabilities Property Plantand Mineral Rights DeferredTaxLiabilitiesPropertyPlantandMineralRights	141549000	USD
CY2019Q4	amr	Deferred Tax Liabilities Property Plantand Mineral Rights DeferredTaxLiabilitiesPropertyPlantandMineralRights	145487000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	22037000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	27140000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	6211000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	6780000	USD
CY2020Q4	amr	Deferred Tax Liabilities Restricted Cash DeferredTaxLiabilitiesRestrictedCash	11516000	USD
CY2019Q4	amr	Deferred Tax Liabilities Restricted Cash DeferredTaxLiabilitiesRestrictedCash	20313000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	55000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	822000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	181368000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	200542000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	480000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	32643000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	133020000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	94802000	USD
CY2020	amr	Valuation Allowance Deferred Tax Asset Increase Decrease Recognizedin Income Tax Expense Amount ValuationAllowanceDeferredTaxAssetIncreaseDecreaseRecognizedinIncomeTaxExpenseAmount	117829000	USD
CY2019	amr	Valuation Allowance Deferred Tax Asset Increase Decrease Recognizedin Income Tax Expense Amount ValuationAllowanceDeferredTaxAssetIncreaseDecreaseRecognizedinIncomeTaxExpenseAmount	29950000	USD
CY2020	amr	Valuation Allowance Deferred Tax Asset Increase Decrease Not Recognizedin Income Tax Expense Amount ValuationAllowanceDeferredTaxAssetIncreaseDecreaseNotRecognizedinIncomeTaxExpenseAmount	12538000	USD
CY2019	amr	Valuation Allowance Deferred Tax Asset Increase Decrease Not Recognizedin Income Tax Expense Amount ValuationAllowanceDeferredTaxAssetIncreaseDecreaseNotRecognizedinIncomeTaxExpenseAmount	8268000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	263387000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	133020000	USD
CY2020	amr	Alternative Minimum Tax Tax Credit Cash Received Sequestration Refund AlternativeMinimumTaxTaxCreditCashReceivedSequestrationRefund	2123000	USD
CY2020Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	1737000000	USD
CY2020Q4	amr	Operating Loss Carryforwards Availablefor Use OperatingLossCarryforwardsAvailableforUse	1011000000	USD
CY2020Q4	amr	Operating Loss Carryforwards Section382 Limitation One OperatingLossCarryforwardsSection382LimitationOne	1000000	USD
CY2020Q4	amr	Operating Loss Carryforwards Amount Subjectto Section382 Limitations One OperatingLossCarryforwardsAmountSubjecttoSection382LimitationsOne	56000000	USD
CY2020Q4	amr	Operating Loss Carryforwards Section382 Limitation Two OperatingLossCarryforwardsSection382LimitationTwo	18300000	USD
CY2020Q4	amr	Operating Loss Carryforwards Amount Subjectto Section382 Limitations Two OperatingLossCarryforwardsAmountSubjecttoSection382LimitationsTwo	324000000	USD
CY2020Q4	amr	Operating Loss Carryforwards Section382 Limitations Three OperatingLossCarryforwardsSection382LimitationsThree	17500000	USD
CY2020Q4	amr	Operating Loss Carryforwards Indefinite Carryforwards OperatingLossCarryforwardsIndefiniteCarryforwards	346000000	USD
CY2020Q4	amr	Tax Credit Carryforwards Section382 Limitation One TaxCreditCarryforwardsSection382LimitationOne	1000000	USD
CY2020Q4	amr	Tax Credit Carryforwards Amount Subjectto Section382 Limitations Two TaxCreditCarryforwardsAmountSubjecttoSection382LimitationsTwo	51000000	USD
CY2020Q4	amr	Tax Credit Carryforwards Section382 Limitation Two TaxCreditCarryforwardsSection382LimitationTwo	17500000	USD
CY2020Q4	us-gaap	Decrease In Unrecognized Tax Benefits Is Reasonably Possible DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible	20788000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	20788000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	5740000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	15048000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	20788000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	20788000	USD
CY2019Q4	amr	Defined Benefit Plan Numberof Plans Amended DefinedBenefitPlanNumberofPlansAmended	2	plan
CY2020Q3	amr	Defined Benefit Plan Plan Assets Increase In Target Allocation Term DefinedBenefitPlanPlanAssetsIncreaseInTargetAllocationTerm	P10M
CY2019	amr	Defined Benefit Plan Plan Assets Level3 Reconciliation Increasefor Business Acquisition DefinedBenefitPlanPlanAssetsLevel3ReconciliationIncreaseforBusinessAcquisition	0	USD
CY2020	us-gaap	Other Comprehensive Income Loss Finalization Of Pension And Non Pension Postretirement Plan Valuation Before Tax OtherComprehensiveIncomeLossFinalizationOfPensionAndNonPensionPostretirementPlanValuationBeforeTax	-14000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Finalization Of Pension And Non Pension Postretirement Plan Valuation Before Tax OtherComprehensiveIncomeLossFinalizationOfPensionAndNonPensionPostretirementPlanValuationBeforeTax	0	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	3613000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	22102000	USD
CY2020	amr	Medical Self Insurance Period Expense MedicalSelfInsurancePeriodExpense	52517000	USD
CY2019	amr	Medical Self Insurance Period Expense MedicalSelfInsurancePeriodExpense	64430000	USD
CY2020Q4	amr	Sharebased Compensation Arrangementby Sharebased Payment Award Numberof Award Types SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofAwardTypes	4	award_type
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	5540000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	12397000	USD
CY2020	us-gaap	Royalty Expense RoyaltyExpense	67992000	USD
CY2019	us-gaap	Royalty Expense RoyaltyExpense	91879000	USD
CY2020Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	64160000	USD
CY2020Q4	amr	Income Tax Receivable Operating Loss Carryforwards IncomeTaxReceivableOperatingLossCarryforwards	5213000	USD
CY2020Q4	us-gaap	Restricted Cash RestrictedCash	105344000	USD
CY2019Q4	us-gaap	Restricted Cash RestrictedCash	134887000	USD
CY2020Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	9311000	USD
CY2019Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	12363000	USD
CY2020Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	96033000	USD
CY2019Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	122524000	USD
CY2020Q4	us-gaap	Restricted Investments RestrictedInvestments	23768000	USD
CY2019Q4	us-gaap	Restricted Investments RestrictedInvestments	19399000	USD
CY2020Q4	us-gaap	Debt Securities Trading Restricted DebtSecuritiesTradingRestricted	22498000	USD
CY2019Q4	us-gaap	Debt Securities Trading Restricted DebtSecuritiesTradingRestricted	11021000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Restricted HeldToMaturitySecuritiesRestricted	1270000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Restricted HeldToMaturitySecuritiesRestricted	8378000	USD
CY2020Q4	us-gaap	Deposit Assets DepositAssets	28247000	USD
CY2019Q4	us-gaap	Deposit Assets DepositAssets	10310000	USD
CY2020	us-gaap	Revenues Revenues	1416187000	USD
CY2019	us-gaap	Revenues Revenues	2001280000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	segment
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2020	us-gaap	Revenues Revenues	1416187000	USD
CY2020	amr	Depreciation Depletion And Amortization Excluding Acquired Intangibles DepreciationDepletionAndAmortizationExcludingAcquiredIntangibles	139885000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	9214000	USD
CY2020	amr	Adjusted Earnings Before Income Tax Interest Depreciation And Amortization AdjustedEarningsBeforeIncomeTaxInterestDepreciationAndAmortization	83402000	USD
CY2020	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	119579000	USD
CY2019	us-gaap	Revenues Revenues	2001280000	USD
CY2019	amr	Depreciation Depletion And Amortization Excluding Acquired Intangibles DepreciationDepletionAndAmortizationExcludingAcquiredIntangibles	215757000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	-3189000	USD
CY2019	amr	Adjusted Earnings Before Income Tax Interest Depreciation And Amortization AdjustedEarningsBeforeIncomeTaxInterestDepreciationAndAmortization	264104000	USD
CY2019	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	160447000	USD
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-241470000	USD
CY2020	us-gaap	Interest Expense InterestExpense	74528000	USD
CY2020	us-gaap	Investment Income Interest InvestmentIncomeInterest	7027000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-2164000	USD
CY2020	amr	Depreciation Depletion And Amortization Excluding Acquired Intangibles DepreciationDepletionAndAmortizationExcludingAcquiredIntangibles	139885000	USD
CY2020	amr	Noncash Allocated Sharebased Compensation Expense NoncashAllocatedSharebasedCompensationExpense	4897000	USD
CY2020	amr	Acquisition Related Obligations Changesin Fair Value Gain Loss AcquisitionRelatedObligationsChangesinFairValueGainLoss	8750000	USD
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	26504000	USD
CY2020	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	83878000	USD
CY2020	amr	Defined Benefit Planand Other Benefit Plan Settlement Gain Loss DefinedBenefitPlanandOtherBenefitPlanSettlementGainLoss	-2966000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	9214000	USD
CY2020	amr	Adjusted Earnings Before Income Tax Interest Depreciation And Amortization AdjustedEarningsBeforeIncomeTaxInterestDepreciationAndAmortization	83402000	USD
CY2020	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	80954000	USD
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-219618000	USD
CY2019	us-gaap	Interest Expense InterestExpense	67521000	USD
CY2019	us-gaap	Investment Income Interest InvestmentIncomeInterest	7247000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-53287000	USD
CY2019	amr	Depreciation Depletion And Amortization Excluding Acquired Intangibles DepreciationDepletionAndAmortizationExcludingAcquiredIntangibles	215757000	USD
CY2019	amr	Business Acquisition Integrationand Other Related Costs BusinessAcquisitionIntegrationandOtherRelatedCosts	1090000	USD
CY2019	amr	Noncash Allocated Sharebased Compensation Expense NoncashAllocatedSharebasedCompensationExpense	12348000	USD
CY2019	amr	Acquisition Related Obligations Changesin Fair Value Gain Loss AcquisitionRelatedObligationsChangesinFairValueGainLoss	3564000	USD
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	23865000	USD
CY2019	amr	Gain Losson Extinguishmentand Modificationof Debt GainLossonExtinguishmentandModificationofDebt	-26459000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	66324000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	124353000	USD
CY2019	amr	Inventory Fair Value Adjustment InventoryFairValueAdjustment	8209000	USD
CY2019	us-gaap	Nonmonetary Transaction Gain Loss Recognized On Transfer NonmonetaryTransactionGainLossRecognizedOnTransfer	9083000	USD
CY2019	amr	Defined Benefit Planand Other Benefit Plan Settlement Gain Loss DefinedBenefitPlanandOtherBenefitPlanSettlementGainLoss	-6446000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	-3189000	USD
CY2019	amr	Adjusted Earnings Before Income Tax Interest Depreciation And Amortization AdjustedEarningsBeforeIncomeTaxInterestDepreciationAndAmortization	264104000	USD
CY2019	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	60169000	USD
CY2019	us-gaap	Restructuring Charges RestructuringCharges	6155000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	124353000	USD
CY2019	us-gaap	Nonmonetary Transaction Gain Loss Recognized On Transfer NonmonetaryTransactionGainLossRecognizedOnTransfer	9083000	USD

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$AMR
Alpha Metallurgical Resources, Inc. Stock $amr

2019 Q4 Form 10-K Financial Statement

#000170471521000026 Filed on March 15, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMR Alpha Metallurgical Resources, Inc. Stock $amr

2019 Q4 Form 10-K Financial Statement

#000170471521000026 Filed on March 15, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMR
Alpha Metallurgical Resources, Inc. Stock $amr