Name:	mgtx_ExpenditureRequirementForGrantFundingOnEligibleMachineryAndEquipment
Namespace Prefix:	mgtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Financial assistance duration period, measured from the date in which capital investments for eligible machinery and equipment are completed, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

Name:	mgtx_FinancialAssistanceDurationFromCompletionOfCapitalInvestment
Namespace Prefix:	mgtx_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Financial assistance duration period, measured from the last date of payment received in IDA Ireland grant funding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

Name:	mgtx_FinancialAssistanceDurationFromLastGrantPayment
Namespace Prefix:	mgtx_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Amount of financial assistance available for each new job created.

No definition available.

Name:	mgtx_GrantAmountForJobCreation
Namespace Prefix:	mgtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of financial assistance available for creation of machinery and equipment that provides opportunities for new jobs.

No definition available.

Name:	mgtx_GrantAmountForMachineryAndEquipment
Namespace Prefix:	mgtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Grant funding available for the creation of machinery and equipment that leads to job creation, expressed as a percent of total cost to produce machinery and equipment.

No definition available.

Name:	mgtx_GrantsForMachineryAndEquipmentAsPercentageOfTotalCostToMake
Namespace Prefix:	mgtx_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Represents the aggregate number of jobs created in order to be eligible to receive financial assistance under IDA Ireland grants.

No definition available.

Name:	mgtx_NumberOfNewJobsCreatedToReceiveGrantFunding
Namespace Prefix:	mgtx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Period benchmark in which the Company may be held to repay a portion of capital grants if a job for which the Company received employment grant funding remains vacant, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

Name:	mgtx_PeriodOfJobVacancyBeforeGrantFundingBecomesRepayable
Namespace Prefix:	mgtx_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 832
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483507/832-10-50-3

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

Name:	us-gaap_GovernmentAssistanceTypeAxis=mgtx_GrantsIdaIrelandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_GovernmentAssistanceTypeAxis=mgtx_GrantsIdaIrelandEmploymentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: