RATE MATTERS AND REGULATION	3 Months Ended
Mar. 31, 2019
Regulated Operations [Abstract]
RATE MATTERS AND REGULATION	RATE MATTERS AND REGULATION KCC Proceedings Westar Energy 2019 Transmission Delivery Charge In March 2019, the State Corporation Commission of the State of Kansas (KCC) issued an order adjusting Westar Energy's retail prices to include updated transmission costs as reflected in the Federal Energy Regulatory Commission (FERC) transmission formula rate (TFR). The new prices were effective in April 2019 and are expected to decrease Westar Energy's annual retail revenues by $7.7 million. KCP&L 2019 Transmission Delivery Charge In April 2019, the KCC issued an order adjusting KCP&L's retail prices to include updated transmission costs as reflected in the FERC TFR. The new prices were effective in May 2019 and are expected to decrease KCP&L's annual retail revenues by $8.3 million. Westar Energy and KCP&L Earnings Review and Sharing Plan (ERSP) As part of their merger settlement agreement with the KCC, Westar Energy and KCP&L agreed to participate in an ERSP for the years 2019 through 2022. Under the ERSP, Westar Energy and KCP&L's Kansas jurisdiction are required to refund to customers 50% of annual earnings in excess of their authorized return on equity of 9.3% to the extent the excess earnings exceed the amount of Westar Energy's and KCP&L's annual merger bill credits for the year being measured. As of March 31, 2019, Westar Energy and KCP&L estimate their 2019 annual earnings will not result in a refund obligation. Westar Energy and KCP&L will file their 2019 earnings calculations with the KCC in March 2020. The final refund obligation, if any, will be decided by the KCC and could vary from the current estimate. MPSC Proceedings GMO Other Proceedings In December 2018, the Office of the Public Counsel (OPC) and the Midwest Energy Consumers Group (MECG) filed a petition with the Public Service Commission of the State of Missouri (MPSC) requesting an accounting authority order that would require GMO to record a regulatory liability for all revenues collected from customers for return on investment, non-fuel operations and maintenance costs, taxes including accumulated deferred income taxes, and all other costs associated with Sibley Station following the station’s retirement in November 2018. GMO already records depreciation expense to a regulatory liability for Sibley Station following its retirement pursuant to GMO’s rate order from its 2018 Missouri rate case. GMO opposes OPC’s and MECG’s petition on various grounds, including the value of costs that OPC and MECG allege are no longer existent due to the retirement of Sibley Station and the fact that the retirement of Sibley Station was a long-planned event that was contemplated as part of the stipulations and agreements in GMO’s 2018 Missouri rate case. The MPSC issued an order in March 2019 adopting a procedural schedule to resolve OPC’s and MECG’s petition. A hearing in the case is scheduled for July 2019 with an order expected in the second half of 2019. FERC Proceedings Westar Energy TFR Westar Energy's TFR, effective in January 2019, includes projected 2019 transmission capital expenditures and operating costs and is expected to decrease annual transmission revenues by $11.2 million when compared to 2018. This updated rate provided the basis for Westar Energy's request with the KCC to adjust its retail prices to include updated transmission costs as discussed above. KCP&L TFR KCP&L's TFR, effective in January 2019, includes projected 2019 transmission capital expenditures and operating costs and is expected to decrease annual transmission revenues by $2.8 million when compared to 2018. This updated rate provided the basis for KCP&L's request with the KCC to adjust its retail prices to include updated transmission costs as discussed above.

RATE MATTERS AND REGULATION

KCC Proceedings

Westar Energy 2019 Transmission Delivery Charge

In March 2019, the State Corporation Commission of the State of Kansas (KCC) issued an order adjusting Westar Energy's retail prices to include updated transmission costs as reflected in the Federal Energy Regulatory Commission (FERC) transmission formula rate (TFR). The new prices were effective in April 2019 and are expected to decrease Westar Energy's annual retail revenues by $7.7 million.

KCP&L 2019 Transmission Delivery Charge

In April 2019, the KCC issued an order adjusting KCP&L's retail prices to include updated transmission costs as reflected in the FERC TFR. The new prices were effective in May 2019 and are expected to decrease KCP&L's annual retail revenues by $8.3 million.

Westar Energy and KCP&L Earnings Review and Sharing Plan (ERSP)

As part of their merger settlement agreement with the KCC, Westar Energy and KCP&L agreed to participate in an ERSP for the years 2019 through 2022. Under the ERSP, Westar Energy and KCP&L's Kansas jurisdiction are required to refund to customers 50% of annual earnings in excess of their authorized return on equity of 9.3% to the extent the excess earnings exceed the amount of Westar Energy's and KCP&L's annual merger bill credits for the year being measured.

As of March 31, 2019, Westar Energy and KCP&L estimate their 2019 annual earnings will not result in a refund obligation. Westar Energy and KCP&L will file their 2019 earnings calculations with the KCC in March 2020. The final refund obligation, if any, will be decided by the KCC and could vary from the current estimate.

MPSC Proceedings

GMO Other Proceedings

In December 2018, the Office of the Public Counsel (OPC) and the Midwest Energy Consumers Group (MECG) filed a petition with the Public Service Commission of the State of Missouri (MPSC) requesting an accounting authority order that would require GMO to record a regulatory liability for all revenues collected from customers for return on investment, non-fuel operations and maintenance costs, taxes including accumulated deferred income taxes, and all other costs associated with Sibley Station following the station’s retirement in November 2018. GMO already records depreciation expense to a regulatory liability for Sibley Station following its retirement pursuant to GMO’s rate order from its 2018 Missouri rate case.

GMO opposes OPC’s and MECG’s petition on various grounds, including the value of costs that OPC and MECG allege are no longer existent due to the retirement of Sibley Station and the fact that the retirement of Sibley Station was a long-planned event that was contemplated as part of the stipulations and agreements in GMO’s 2018 Missouri rate case.

The MPSC issued an order in March 2019 adopting a procedural schedule to resolve OPC’s and MECG’s petition. A hearing in the case is scheduled for July 2019 with an order expected in the second half of 2019.

FERC Proceedings

Westar Energy TFR

Westar Energy's TFR, effective in January 2019, includes projected 2019 transmission capital expenditures and operating costs and is expected to decrease annual transmission revenues by $11.2 million when compared to 2018. This updated rate provided the basis for Westar Energy's request with the KCC to adjust its retail prices to include updated transmission costs as discussed above.

KCP&L TFR

KCP&L's TFR, effective in January 2019, includes projected 2019 transmission capital expenditures and operating costs and is expected to decrease annual transmission revenues by $2.8 million when compared to 2018. This updated rate provided the basis for KCP&L's request with the KCC to adjust its retail prices to include updated transmission costs as discussed above.