3.22.0.1 html 274 481 1 false 111 0 false 8 false false R1.htm 1001 - Document - Cover Page Sheet http://www.montaukenergy.com/role/CoverPage Cover Page Cover 1 false false R2.htm 1002 - Statement - CONSOLIDATED BALANCE SHEETS Sheet http://www.montaukenergy.com/role/ConsolidatedBalanceSheets CONSOLIDATED BALANCE SHEETS Statements 2 false false R3.htm 1003 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical) Sheet http://www.montaukenergy.com/role/ConsolidatedBalanceSheetsParenthetical CONSOLIDATED BALANCE SHEETS (Parenthetical) Statements 3 false false R4.htm 1004 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS Sheet http://www.montaukenergy.com/role/ConsolidatedStatementsOfOperations CONSOLIDATED STATEMENTS OF OPERATIONS Statements 4 false false R5.htm 1005 - Statement - CONSOLIDATED STATEMENTS OF STOCKHOLDERS' AND MEMBER'S EQUITY Sheet http://www.montaukenergy.com/role/ConsolidatedStatementsOfStockholdersAndMemberSEquity CONSOLIDATED STATEMENTS OF STOCKHOLDERS' AND MEMBER'S EQUITY Statements 5 false false R6.htm 1006 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS Sheet http://www.montaukenergy.com/role/ConsolidatedStatementsOfCashFlows CONSOLIDATED STATEMENTS OF CASH FLOWS Statements 6 false false R7.htm 1007 - Disclosure - Description of Business Sheet http://www.montaukenergy.com/role/DescriptionOfBusiness Description of Business Notes 7 false false R8.htm 1008 - Disclosure - Summary of Significant Accounting Policies Sheet http://www.montaukenergy.com/role/SummaryOfSignificantAccountingPolicies Summary of Significant Accounting Policies Notes 8 false false R9.htm 1009 - Disclosure - Asset Impairment Sheet http://www.montaukenergy.com/role/AssetImpairment Asset Impairment Notes 9 false false R10.htm 1010 - Disclosure - Revenues from Contracts with Customers Sheet http://www.montaukenergy.com/role/RevenuesFromContractsWithCustomers Revenues from Contracts with Customers Notes 10 false false R11.htm 1011 - Disclosure - Accounts and Other Receivables Sheet http://www.montaukenergy.com/role/AccountsAndOtherReceivables Accounts and Other Receivables Notes 11 false false R12.htm 1012 - Disclosure - Assets Held For Sale Sheet http://www.montaukenergy.com/role/AssetsHeldForSale Assets Held For Sale Notes 12 false false R13.htm 1013 - Disclosure - Property, Plant and Equipment, Net Sheet http://www.montaukenergy.com/role/PropertyPlantAndEquipmentNet Property, Plant and Equipment, Net Notes 13 false false R14.htm 1014 - Disclosure - Goodwill And Intangible Assets, Net Sheet http://www.montaukenergy.com/role/GoodwillAndIntangibleAssetsNet Goodwill And Intangible Assets, Net Notes 14 false false R15.htm 1015 - Disclosure - Assets Retirement Obligations Sheet http://www.montaukenergy.com/role/AssetsRetirementObligations Assets Retirement Obligations Notes 15 false false R16.htm 1016 - Disclosure - Derivative Instruments Sheet http://www.montaukenergy.com/role/DerivativeInstruments Derivative Instruments Notes 16 false false R17.htm 1017 - Disclosure - Fair Value of Financial Instruments Sheet http://www.montaukenergy.com/role/FairValueOfFinancialInstruments Fair Value of Financial Instruments Notes 17 false false R18.htm 1018 - Disclosure - Accrued Liabilities Sheet http://www.montaukenergy.com/role/AccruedLiabilities Accrued Liabilities Notes 18 false false R19.htm 1019 - Disclosure - Debt Sheet http://www.montaukenergy.com/role/Debt Debt Notes 19 false false R20.htm 1020 - Disclosure - Income Taxes Sheet http://www.montaukenergy.com/role/IncomeTaxes Income Taxes Notes 20 false false R21.htm 1021 - Disclosure - Share-Based Compensation Sheet http://www.montaukenergy.com/role/ShareBasedCompensation Share-Based Compensation Notes 21 false false R22.htm 1022 - Disclosure - Defined Contribution Plan Sheet http://www.montaukenergy.com/role/DefinedContributionPlan Defined Contribution Plan Notes 22 false false R23.htm 1023 - Disclosure - Related Party Transactions Sheet http://www.montaukenergy.com/role/RelatedPartyTransactions Related Party Transactions Notes 23 false false R24.htm 1024 - Disclosure - Segment Information Sheet http://www.montaukenergy.com/role/SegmentInformation Segment Information Notes 24 false false R25.htm 1025 - Disclosure - Leases Sheet http://www.montaukenergy.com/role/Leases Leases Notes 25 false false R26.htm 1026 - Disclosure - Commitments And Contingencies Sheet http://www.montaukenergy.com/role/CommitmentsAndContingencies Commitments And Contingencies Notes 26 false false R27.htm 1027 - Disclosure - Quarterly Financial Data (Unaudited) Sheet http://www.montaukenergy.com/role/QuarterlyFinancialDataUnaudited Quarterly Financial Data (Unaudited) Notes 27 false false R28.htm 1028 - Disclosure - Earnings (loss) per share Sheet http://www.montaukenergy.com/role/EarningsLossPerShare Earnings (loss) per share Notes 28 false false R29.htm 1029 - Disclosure - Subsequent Events Sheet http://www.montaukenergy.com/role/SubsequentEvents Subsequent Events Notes 29 false false R30.htm 1030 - Disclosure - Summary of Significant Accounting Policies (Policies) Sheet http://www.montaukenergy.com/role/SummaryOfSignificantAccountingPoliciesPolicies Summary of Significant Accounting Policies (Policies) Policies http://www.montaukenergy.com/role/SummaryOfSignificantAccountingPolicies 30 false false R31.htm 1031 - Disclosure - Summary of Significant Accounting Policies (Tables) Sheet http://www.montaukenergy.com/role/SummaryOfSignificantAccountingPoliciesTables Summary of Significant Accounting Policies (Tables) Tables http://www.montaukenergy.com/role/SummaryOfSignificantAccountingPolicies 31 false false R32.htm 1032 - Disclosure - Revenues from Contracts with Customers (Tables) Sheet http://www.montaukenergy.com/role/RevenuesFromContractsWithCustomersTables Revenues from Contracts with Customers (Tables) Tables http://www.montaukenergy.com/role/RevenuesFromContractsWithCustomers 32 false false R33.htm 1033 - Disclosure - Accounts and Other Receivables (Tables) Sheet http://www.montaukenergy.com/role/AccountsAndOtherReceivablesTables Accounts and Other Receivables (Tables) Tables http://www.montaukenergy.com/role/AccountsAndOtherReceivables 33 false false R34.htm 1034 - Disclosure - Property, Plant and Equipment, Net (Tables) Sheet http://www.montaukenergy.com/role/PropertyPlantAndEquipmentNetTables Property, Plant and Equipment, Net (Tables) Tables http://www.montaukenergy.com/role/PropertyPlantAndEquipmentNet 34 false false R35.htm 1035 - Disclosure - Goodwill And Intangible Assets, Net (Tables) Sheet http://www.montaukenergy.com/role/GoodwillAndIntangibleAssetsNetTables Goodwill And Intangible Assets, Net (Tables) Tables http://www.montaukenergy.com/role/GoodwillAndIntangibleAssetsNet 35 false false R36.htm 1036 - Disclosure - Asset Retirement Obligations (Tables) Sheet http://www.montaukenergy.com/role/AssetRetirementObligationsTables Asset Retirement Obligations (Tables) Tables 36 false false R37.htm 1037 - Disclosure - Derivative Instruments (Tables) Sheet http://www.montaukenergy.com/role/DerivativeInstrumentsTables Derivative Instruments (Tables) Tables http://www.montaukenergy.com/role/DerivativeInstruments 37 false false R38.htm 1038 - Disclosure - Fair Value of Financial Instruments (Tables) Sheet http://www.montaukenergy.com/role/FairValueOfFinancialInstrumentsTables Fair Value of Financial Instruments (Tables) Tables http://www.montaukenergy.com/role/FairValueOfFinancialInstruments 38 false false R39.htm 1039 - Disclosure - Accrued Liabilities (Tables) Sheet http://www.montaukenergy.com/role/AccruedLiabilitiesTables Accrued Liabilities (Tables) Tables http://www.montaukenergy.com/role/AccruedLiabilities 39 false false R40.htm 1040 - Disclosure - Debt (Table) Sheet http://www.montaukenergy.com/role/DebtTable Debt (Table) Tables http://www.montaukenergy.com/role/Debt 40 false false R41.htm 1041 - Disclosure - Income Taxes (Tables) Sheet http://www.montaukenergy.com/role/IncomeTaxesTables Income Taxes (Tables) Tables http://www.montaukenergy.com/role/IncomeTaxes 41 false false R42.htm 1042 - Disclosure - Share-Based Compensation (Tables) Sheet http://www.montaukenergy.com/role/ShareBasedCompensationTables Share-Based Compensation (Tables) Tables http://www.montaukenergy.com/role/ShareBasedCompensation 42 false false R43.htm 1043 - Disclosure - Segment Information (Tables) Sheet http://www.montaukenergy.com/role/SegmentInformationTables Segment Information (Tables) Tables http://www.montaukenergy.com/role/SegmentInformation 43 false false R44.htm 1044 - Disclosure - Leases (Tables) Sheet http://www.montaukenergy.com/role/LeasesTables Leases (Tables) Tables http://www.montaukenergy.com/role/Leases 44 false false R45.htm 1045 - Disclosure - Quarterly Financial Data (Unaudited) - (Table) Sheet http://www.montaukenergy.com/role/QuarterlyFinancialDataUnauditedTable Quarterly Financial Data (Unaudited) - (Table) Tables http://www.montaukenergy.com/role/QuarterlyFinancialDataUnaudited 45 false false R46.htm 1046 - Disclosure - Earnings (loss) per share (Tables) Sheet http://www.montaukenergy.com/role/EarningsLossPerShareTables Earnings (loss) per share (Tables) Tables http://www.montaukenergy.com/role/EarningsLossPerShare 46 false false R47.htm 1047 - Disclosure - Description of Business - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/DescriptionOfBusinessAdditionalInformationDetail Description of Business - Additional Information (Detail) Details 47 false false R48.htm 1048 - Disclosure - Summary of Significant Accounting Policies - Summary of Useful Lives of Property Plant and Equipment (Detail) Sheet http://www.montaukenergy.com/role/SummaryOfSignificantAccountingPoliciesSummaryOfUsefulLivesOfPropertyPlantAndEquipmentDetail Summary of Significant Accounting Policies - Summary of Useful Lives of Property Plant and Equipment (Detail) Details 48 false false R49.htm 1049 - Disclosure - Summary of Significant Accounting Policies - Summary of Useful Lives of Property Plant and Equipment (Detail) (Parenthetical) Sheet http://www.montaukenergy.com/role/SummaryOfSignificantAccountingPoliciesSummaryOfUsefulLivesOfPropertyPlantAndEquipmentDetailParenthetical Summary of Significant Accounting Policies - Summary of Useful Lives of Property Plant and Equipment (Detail) (Parenthetical) Details 49 false false R50.htm 1050 - Disclosure - Summary of Significant Accounting Policies - Summary of Useful Lives of Intangible Assets Other than Goodwill (Detail) Sheet http://www.montaukenergy.com/role/SummaryOfSignificantAccountingPoliciesSummaryOfUsefulLivesOfIntangibleAssetsOtherThanGoodwillDetail Summary of Significant Accounting Policies - Summary of Useful Lives of Intangible Assets Other than Goodwill (Detail) Details 50 false false R51.htm 1051 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/SummaryOfSignificantAccountingPoliciesAdditionalInformationDetail Summary of Significant Accounting Policies - Additional Information (Detail) Details 51 false false R52.htm 1052 - Disclosure - Asset Impairment - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/AssetImpairmentAdditionalInformationDetail Asset Impairment - Additional Information (Detail) Details 52 false false R53.htm 1053 - Disclosure - Revenues from Contracts with Customers - Summary of Company's Revenue by Major Source (Detail) Sheet http://www.montaukenergy.com/role/RevenuesFromContractsWithCustomersSummaryOfCompanysRevenueByMajorSourceDetail Revenues from Contracts with Customers - Summary of Company's Revenue by Major Source (Detail) Details 53 false false R54.htm 1054 - Disclosure - Revenues from Contracts with Customers - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/RevenuesFromContractsWithCustomersAdditionalInformationDetail Revenues from Contracts with Customers - Additional Information (Detail) Details 54 false false R55.htm 1055 - Disclosure - Accounts and Other Receivables - Schedule of Accounts and Other Receivables (Detail) Sheet http://www.montaukenergy.com/role/AccountsAndOtherReceivablesScheduleOfAccountsAndOtherReceivablesDetail Accounts and Other Receivables - Schedule of Accounts and Other Receivables (Detail) Details 55 false false R56.htm 1056 - Disclosure - Accounts and Other Receivables - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/AccountsAndOtherReceivablesAdditionalInformationDetail Accounts and Other Receivables - Additional Information (Detail) Details 56 false false R57.htm 1057 - Disclosure - Assets Held For Sale -Additional Information (Detail) Sheet http://www.montaukenergy.com/role/AssetsHeldForSaleAdditionalInformationDetail Assets Held For Sale -Additional Information (Detail) Details 57 false false R58.htm 1058 - Disclosure - Property, Plant and Equipment, Net - Summary of Property Plant and Equipment (Detail) Sheet http://www.montaukenergy.com/role/PropertyPlantAndEquipmentNetSummaryOfPropertyPlantAndEquipmentDetail Property, Plant and Equipment, Net - Summary of Property Plant and Equipment (Detail) Details 58 false false R59.htm 1059 - Disclosure - Property, Plant and Equipment, Net - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/PropertyPlantAndEquipmentNetAdditionalInformationDetail Property, Plant and Equipment, Net - Additional Information (Detail) Details 59 false false R60.htm 1060 - Disclosure - Goodwill And Intangible Assets, Net - Schedule of Intangible Assets (Detail) Sheet http://www.montaukenergy.com/role/GoodwillAndIntangibleAssetsNetScheduleOfIntangibleAssetsDetail Goodwill And Intangible Assets, Net - Schedule of Intangible Assets (Detail) Details 60 false false R61.htm 1061 - Disclosure - Goodwill And Intangible Assets, Net - Schedule of Intangible Assets (Detail) (Parenthetical) Sheet http://www.montaukenergy.com/role/GoodwillAndIntangibleAssetsNetScheduleOfIntangibleAssetsDetailParenthetical Goodwill And Intangible Assets, Net - Schedule of Intangible Assets (Detail) (Parenthetical) Details 61 false false R62.htm 1062 - Disclosure - Goodwill And Intangible Assets, Net - Schedule of Finite Lived Intangible Assets Future Amortization Expense (Detail) Sheet http://www.montaukenergy.com/role/GoodwillAndIntangibleAssetsNetScheduleOfFiniteLivedIntangibleAssetsFutureAmortizationExpenseDetail Goodwill And Intangible Assets, Net - Schedule of Finite Lived Intangible Assets Future Amortization Expense (Detail) Details 62 false false R63.htm 1063 - Disclosure - Goodwill And Intangible Assets, Net - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/GoodwillAndIntangibleAssetsNetAdditionalInformationDetail Goodwill And Intangible Assets, Net - Additional Information (Detail) Details 63 false false R64.htm 1064 - Disclosure - Assets Retirement Obligations - Summary of Activity Associated with Asset Retirement Obligations (Detail) Sheet http://www.montaukenergy.com/role/AssetsRetirementObligationsSummaryOfActivityAssociatedWithAssetRetirementObligationsDetail Assets Retirement Obligations - Summary of Activity Associated with Asset Retirement Obligations (Detail) Details 64 false false R65.htm 1065 - Disclosure - Derivative Instruments - Summary of Realized and Unrealized Gains and Losses of Derivative Instrument (Detail) Sheet http://www.montaukenergy.com/role/DerivativeInstrumentsSummaryOfRealizedAndUnrealizedGainsAndLossesOfDerivativeInstrumentDetail Derivative Instruments - Summary of Realized and Unrealized Gains and Losses of Derivative Instrument (Detail) Details 65 false false R66.htm 1066 - Disclosure - Fair Value of Financial Instruments - Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) Sheet http://www.montaukenergy.com/role/FairValueOfFinancialInstrumentsSummaryOfAssetsAndLiabilitiesMeasuredAtFairValueOnARecurringBasisDetail Fair Value of Financial Instruments - Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) Details 66 false false R67.htm 1067 - Disclosure - Accrued Liabilities - Summary of Accrued Liabilities (Detail) Sheet http://www.montaukenergy.com/role/AccruedLiabilitiesSummaryOfAccruedLiabilitiesDetail Accrued Liabilities - Summary of Accrued Liabilities (Detail) Details 67 false false R68.htm 1068 - Disclosure - Debt - Summary of Company Debt (Detail) Sheet http://www.montaukenergy.com/role/DebtSummaryOfCompanyDebtDetail Debt - Summary of Company Debt (Detail) Details 68 false false R69.htm 1069 - Disclosure - Debt - Summary of Annual Principal Maturities (Details) Sheet http://www.montaukenergy.com/role/DebtSummaryOfAnnualPrincipalMaturitiesDetails Debt - Summary of Annual Principal Maturities (Details) Details 69 false false R70.htm 1070 - Disclosure - Debt - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/DebtAdditionalInformationDetail Debt - Additional Information (Detail) Details 70 false false R71.htm 1071 - Disclosure - Income Taxes - Schedule of components of income tax provision benefit (Detail) Sheet http://www.montaukenergy.com/role/IncomeTaxesScheduleOfComponentsOfIncomeTaxProvisionBenefitDetail Income Taxes - Schedule of components of income tax provision benefit (Detail) Details 71 false false R72.htm 1072 - Disclosure - Income Taxes - Schedule Of Deferred Tax Assets And Liabilities (Detail) Sheet http://www.montaukenergy.com/role/IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail Income Taxes - Schedule Of Deferred Tax Assets And Liabilities (Detail) Details 72 false false R73.htm 1073 - Disclosure - Income Taxes - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/IncomeTaxesAdditionalInformationDetail Income Taxes - Additional Information (Detail) Details 73 false false R74.htm 1074 - Disclosure - Share-Based Compensation - Summary of Fair Value of MRI EICP Options and Valuation Assumptions (Detail) Sheet http://www.montaukenergy.com/role/ShareBasedCompensationSummaryOfFairValueOfMriEicpOptionsAndValuationAssumptionsDetail Share-Based Compensation - Summary of Fair Value of MRI EICP Options and Valuation Assumptions (Detail) Details 74 false false R75.htm 1075 - Disclosure - Share-Based Compensation - Summary of Outstanding Activity of Options,Restricted Stock and Restricted Stock Units under MRI EICP (Detail) Sheet http://www.montaukenergy.com/role/ShareBasedCompensationSummaryOfOutstandingActivityOfOptionsRestrictedStockAndRestrictedStockUnitsUnderMriEicpDetail Share-Based Compensation - Summary of Outstanding Activity of Options,Restricted Stock and Restricted Stock Units under MRI EICP (Detail) Details 75 false false R76.htm 1076 - Disclosure - Share-Based Compensation - Summary of Outstanding Activity of Options and Restricted Stock under SAR Plan (Detail) Sheet http://www.montaukenergy.com/role/ShareBasedCompensationSummaryOfOutstandingActivityOfOptionsAndRestrictedStockUnderSarPlanDetail Share-Based Compensation - Summary of Outstanding Activity of Options and Restricted Stock under SAR Plan (Detail) Details 76 false false R77.htm 1077 - Disclosure - Share-Based Compensation - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/ShareBasedCompensationAdditionalInformationDetail Share-Based Compensation - Additional Information (Detail) Details 77 false false R78.htm 1078 - Disclosure - Defined Contribution Plan - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/DefinedContributionPlanAdditionalInformationDetail Defined Contribution Plan - Additional Information (Detail) Details 78 false false R79.htm 1079 - Disclosure - Related Party Transactions - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/RelatedPartyTransactionsAdditionalInformationDetail Related Party Transactions - Additional Information (Detail) Details 79 false false R80.htm 1080 - Disclosure - Segment Information - Summary of Reconciliation of the Company's Reportable Segments' Net Income from Continuing Operations (Detail) Sheet http://www.montaukenergy.com/role/SegmentInformationSummaryOfReconciliationOfTheCompanySReportableSegmentsNetIncomeFromContinuingOperationsDetail Segment Information - Summary of Reconciliation of the Company's Reportable Segments' Net Income from Continuing Operations (Detail) Details 80 false false R81.htm 1081 - Disclosure - Segment Information - Summary of Revenue by Major Customers (Detail) Sheet http://www.montaukenergy.com/role/SegmentInformationSummaryOfRevenueByMajorCustomersDetail Segment Information - Summary of Revenue by Major Customers (Detail) Details 81 false false R82.htm 1082 - Disclosure - Leases - Summary of Supplemental Information Related To Operating Leases (Detail) Sheet http://www.montaukenergy.com/role/LeasesSummaryOfSupplementalInformationRelatedToOperatingLeasesDetail Leases - Summary of Supplemental Information Related To Operating Leases (Detail) Details 82 false false R83.htm 1083 - Disclosure - Leases - Summary of Future Minimum Lease Payments (Detail) Sheet http://www.montaukenergy.com/role/LeasesSummaryOfFutureMinimumLeasePaymentsDetail Leases - Summary of Future Minimum Lease Payments (Detail) Details 83 false false R84.htm 1084 - Disclosure - Leases - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/LeasesAdditionalInformationDetail Leases - Additional Information (Detail) Details 84 false false R85.htm 1085 - Disclosure - Commitments and Contingencies - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/CommitmentsAndContingenciesAdditionalInformationDetail Commitments and Contingencies - Additional Information (Detail) Details 85 false false R86.htm 1086 - Disclosure - Quarterly Financial Data (Unaudited) - Schedule Of Quarterly Financial Information (Detail) Sheet http://www.montaukenergy.com/role/QuarterlyFinancialDataUnauditedScheduleOfQuarterlyFinancialInformationDetail Quarterly Financial Data (Unaudited) - Schedule Of Quarterly Financial Information (Detail) Details http://www.montaukenergy.com/role/QuarterlyFinancialDataUnauditedTable 86 false false R87.htm 1087 - Disclosure - Quarterly Financial Data (Unaudited) - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/QuarterlyFinancialDataUnauditedAdditionalInformationDetail Quarterly Financial Data (Unaudited) - Additional Information (Detail) Details http://www.montaukenergy.com/role/QuarterlyFinancialDataUnauditedTable 87 false false R88.htm 1088 - Disclosure - Earnings (loss) per share - Schedule of Loss Per Share, Basic and Diluted (Detail) Sheet http://www.montaukenergy.com/role/EarningsLossPerShareScheduleOfLossPerShareBasicAndDilutedDetail Earnings (loss) per share - Schedule of Loss Per Share, Basic and Diluted (Detail) Details http://www.montaukenergy.com/role/EarningsLossPerShareTables 88 false false R89.htm 1089 - Disclosure - Earnings (loss) per share - Additional Information (Detail) Sheet http://www.montaukenergy.com/role/EarningsLossPerShareAdditionalInformationDetail Earnings (loss) per share - Additional Information (Detail) Details http://www.montaukenergy.com/role/EarningsLossPerShareTables 89 false false All Reports Book All Reports d260478d10k.htm d260478dex211.htm d260478dex231.htm d260478dex241.htm d260478dex311.htm d260478dex312.htm d260478dex321.htm d260478dex322.htm mntk-20211231.xsd mntk-20211231_cal.xml mntk-20211231_def.xml mntk-20211231_lab.xml mntk-20211231_pre.xml g260478g01a01.jpg g260478g02a02.jpg g260478g03a03.jpg g260478g35a35.jpg http://fasb.org/us-gaap/2021-01-31 http://xbrl.sec.gov/dei/2021q4 true true