Commitments and Contingencies (Details-1)	Sep. 30, 2020 MW
Minimum [Member]
EPA Greenhouse Gas Reduction Guidelines
Standard of Performance Plan For EGUs Over Threshold	25

The ACE proposal directs states to submit plans to the EPA for approval that implement standards of performance (called Best System of Emissions Reductions, or BSER) for individual EGUs over a certain threshold.

No definition available.

Name:	mgee_Epagreenhousegasreductionguidlinesstandardofperformanceforegus
Namespace Prefix:	mgee_
Data Type:	num:powerItemType
Balance Type:	na
Period Type:	instant