XML 74 R52.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Share-Based Compensation (Tables) - Performance Units [Member] | 12 Months Ended
--- | ---
Dec. 31, 2015
Performance Unit Plan [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Performance Unit Graded Vesting Schedule | Under MGE Energy's Performance Unit Plan, eligible employees may receive performance units that entitle the holder to receive a cash payment equal to the value of a designated number of shares of MGE Energy's common stock, plus dividend equivalent payments thereon, at the end of the set performance period. In accor dance with the plan's provisions, these awards are subject to a prescribed vesting schedule and must be settled in cash. Accordingly, no shares of common stock will be issued in connection with the plan. On the grant d ate, MGE Energy and MGE measure the cost of the employee services received in exchange for a performance unit award based on the current market value of MGE Energy common stock. The fair value of the awards is re-measured quarterly, including at December 31, 2015, as required by applicable a ccounting standards. Changes in fair value as well as the original grant are recognized as compensation cost. Since this amount is re-measured throughout the vesting period, the compensation co st is subject to variability. Units are subject to a five-year graded vesting schedule.
| Grant Date |  | MGE Energy Units Granted |
| February 19, 2016 |  | 19,055 |
| February 20, 2015 |  | 18,948 |
| February 21, 2014 |  | 21,991 |
| February 15, 2013 |  | 22,884 |
| February 17, 2012 |  | 25,040 |
Director Incentive Agreement [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Performance Unit Graded Vesting Schedule | Under the Director Incentive Plan, a non-employee director can receive performance units that entitle the holder to receive a cash payment equal to the value of a designated number of shares of MGE Energy’s common stock, plus dividend payments, at the end o f the set performance period. The units are subject to a thre e-year graded vesting schedule. This plan is similar to MGE Energy’s Performance Unit Plan for eligi ble employees described above.
| Grant Date |  | MGE Energy Units Granted |
| January 15, 2016 |  | 3,773 |
| January 16, 2015 |  | 3,794 |
| January 17, 2014 |  | 4,683 |

X
- Definition Tabular disclosure of components of a stock option or other award plan under which equity-based compensation is awarded to employees, typically comprised of the amount of unearned compensation (deferred compensation cost), compensation expense, and changes in the quantity and fair value of the shares (or other type of equity) granted, exercised, forfeited, and issued and outstanding pertaining to that plan. Disclosure may also include nature and general terms of such arrangements that existed during the period and potential effects of those arrangements on shareholders, effect of compensation cost arising from equity-based payment arrangements on the income statement, method of estimating the fair value of the goods or services received, or the fair value of the equity instruments granted, during the period, cash flow effects resulting from equity-based payment arrangements and, for registrants that accelerate vesting of out of the money share options, reasons for the decision to accelerate. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 + Details
Name: | us-gaap_DisclosureOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- 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 No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_PlanNameAxis=mgee_PerformanceUnitPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_PerformanceSharesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PlanNameAxis=mgee_DirectorIncentiveAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |