Retirement Plan (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Retirement Plan [Abstract]
Allocated contributions	$ (10,295)
Allocated contributions and expense		$ 17,746

Amount of increase (decrease) in discretionary contributions made by an employer to a defined contribution plan.

No definition available.

Name:	mghl_IncreaseDecreaseInDefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix:	mghl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration