Number of employees.

No definition available.

Name:	mntk_NumberOfEmployees
Namespace Prefix:	mntk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Share based compensation arrangement by share based payment award, equity instruments other than options revalued amount.

+ References

No definition available.

+ Details

Name:	mntk_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsRevaluedAmount
Namespace Prefix:	mntk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of noncash expense for award of restricted stock or unit under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

+ Details

Name:	us-gaap_RestrictedStockExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of noncash expense for share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

+ Details

Name:	us-gaap_ShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesPerEmployee
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_GeneralAndAdministrativeExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=mntk_MontaukRenewablesIncEquityAndIncentiveCompensationPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=mntk_TimeBasedRestrictedStockAwardsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Share-Based Compensation - Additional Information (Detail) shares in Thousands		3 Months Ended		6 Months Ended
	May 31, 2022 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) Employees shares	Jun. 30, 2025 USD ($)
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation				$ 1,151,000	$ 3,639,000
General and Administrative Expense [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Non cash stock compensation expense			$ 1,550,000
MRI EICP [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation				$ 3,756,000
Unrecognised compensation expense recognised, Period				5 years
Compensation cost not yet recognized		$ 0		$ 0
Restricted Stock [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation		516,000	926,000	$ 1,151,000	1,780,000
Share-based compensation arrangement by share-based payment award, maximum number of shares per employee \| shares				1,250
Number of employees \| Employees				2
Time Based Restricted Stock Awards [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation		$ 0	$ 1,442,000	$ 0	$ 1,863,000
Share-Based compensation arrangement by share-Based payment award, equity instruments other than options, revalued amount	$ 15,500,000