Share-Based Compensation

3 Months Ended

Mar. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Share-Based Compensation

Share-Based Compensation - MGE Energy and MGE.

Under MGE Energy'sDirector Incentive Plan and Performance Unit Plan, non-employee directorsand 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 2018, 5,810units were granted under the Director Incentive Plan and are subject to a three-year graded vesting schedule and 17,830 units were granted under the Performance Unit Plan and are subject to a five-year graded vesting schedule. On the grant date, the cost of the director or employee services received in exchange for a performance unit award is measured based on the current market value of MGE Energy common stock. The fair value of the awards is re-measured quarterly, including atMarch 31,2018, as required by applicable accounting 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 cost is subject to variability.

For nonretirement eligible employees under the Performance Unit Plan, stock based compensation costs are accrued and recognized using the graded vesting method. Compensation cost for retirement eligible employees or employees that will become retirement eligible during the vesting schedule are recognized on an abridged horizon.

During the three months endedMarch 31,2018, MGE recorded $0.2 million in compensation expense as a result of awards under the plans compared to $0.5 million for the comparable period in 2017. In January 2018, cash payments of $1.6 million were distributed relating to awards that were granted under the plans. No forfeitures of units occurred during the three months endedMarch 31,2018 and 2017. At March 31,2018, $4.8 million of outstanding awards are vested, and of this amount, no cash settlements have occurred.