Regulatory Matters	6 Months Ended
Jun. 30, 2017
Regulated Operations [Abstract]
Regulatory Matters	6. REGULATORY MATTERS KCP&L Kansas 2016 Abbreviated Rate Case Proceedings In November 2016, KCP&L filed an abbreviated application with KCC to request a decrease to its retail revenues of $2.8 million, reflecting the true-up to actuals of construction and environmental upgrade costs at the La Cygne station and Wolf Creek capital addition costs and the removal of certain regulatory asset and liability amortizations. The previously approved return on equity and rate-making ratio for KCP&L was not addressed in this case. In April 2017, KCP&L, KCC staff and the Citizens' Utility Ratepayer Board filed a joint motion to approve a unanimous settlement agreement with KCC that requested a decrease in retail revenues of $3.6 million. In June 2017, KCC issued an order approving the unanimous settlement agreement. The rates established by the order took effect on June 28, 2017. KCP&L Missouri 2016 Rate Case Proceedings In July 2016, KCP&L filed an application with the MPSC to request an increase to its retail revenues of $62.9 million, with a return on equity of 9.9% and a rate-making equity ratio of 49.88%. The request reflects increases in infrastructure investment costs, costs for regional transmission lines, property tax costs and costs to comply with environmental and cybersecurity mandates. KCP&L also requested an additional $27.2 million increase associated with rebasing fuel and purchased power expense. In May 2017, the MPSC issued an order for KCP&L authorizing an increase in annual revenues of $32.5 million, a return on equity of 9.5% and a rate-making equity ratio of approximately 49.2%. The rates established by the order took effect on June 8, 2017.

6. REGULATORY MATTERS

KCP&L Kansas 2016 Abbreviated Rate Case Proceedings

In November 2016, KCP&L filed an abbreviated application with KCC to request a decrease to its retail revenues of $2.8 million, reflecting the true-up to actuals of construction and environmental upgrade costs at the La Cygne station and Wolf Creek capital addition costs and the removal of certain regulatory asset and liability amortizations. The previously approved return on equity and rate-making ratio for KCP&L was not addressed in this case. In April 2017, KCP&L, KCC staff and the Citizens' Utility Ratepayer Board filed a joint motion to approve a unanimous settlement agreement with KCC that requested a decrease in retail revenues of $3.6 million. In June 2017, KCC issued an order approving the unanimous settlement agreement. The rates established by the order took effect on June 28, 2017.

KCP&L Missouri 2016 Rate Case Proceedings

In July 2016, KCP&L filed an application with the MPSC to request an increase to its retail revenues of $62.9 million, with a return on equity of 9.9% and a rate-making equity ratio of 49.88%. The request reflects increases in infrastructure investment costs, costs for regional transmission lines, property tax costs and costs to comply with environmental and cybersecurity mandates. KCP&L also requested an additional $27.2 million increase associated with rebasing fuel and purchased power expense.

In May 2017, the MPSC issued an order for KCP&L authorizing an increase in annual revenues of $32.5 million, a return on equity of 9.5% and a rate-making equity ratio of approximately 49.2%. The rates established by the order took effect on June 8, 2017.