Rate Matters and Regulation	3 Months Ended
Mar. 31, 2015
Regulated Operations [Abstract]
Rate Matters and Regulation	Rate Matters and Regulation Except as set forth below, the circumstances set forth in Note 15 to the Company's Consolidated Financial Statements included in the Company's 2014 Form 10-K appropriately represent, in all material respects, the current status of the Company's regulatory matters. Arkansas Regulatory Developments The State of Arkansas recently enacted two laws related to rate filings. Act 725, among other things, provides a public utility the option, to be exercised concurrently with the filing of a general rate application, to file notice of its intent to exercise its right for an annual formula rate review so as to provide a streamlined review of the utility’s rates to determine if adjustments in rates are justified. If the utility exercises such rights, rates may be adjusted if the earned return rate is 0.5 percent above or below the target return rate. This procedure is expected to reduce regulatory lag in Arkansas. Act 725 additionally allows for evidence to be presented, relative to the calculation of the return on common equity, comparing the requested return on common equity to approved returns on common equity for public utilities delivering similar services with corresponding risks within Arkansas and also in similar regulatory jurisdictions in the same general part of the country. Act 1000 amends and clarifies existing interim rate requirements to expand the types of expenses that may be recorded and specifically authorize the recovery of allowance for funds used during construction. Act 1000 allows a public utility to file for an interim rate schedule through which it may recover investments and expenses, including allowance for funds used during construction, expended complying with legislative or administrative rules, regulations, or requirements related to the protection of the public, health, safety, or the environment. Rates are implemented at the time of filing of the interim rate schedule, subject to refund. Pending Regulatory Matters Environmental Compliance Plan On August 6, 2014, OG&E filed an application with the OCC for approval of its plan to comply with EPA’s MATS and Regional Haze FIP while serving the best long-term interests of customers in light of future environmental uncertainties. The application seeks approval of the environmental compliance plan and for a recovery mechanism for the associated costs. The environmental compliance plan includes installing dry scrubbers at Sooner Units 1 and 2 and the conversion of Muskogee Units 4 and 5 to natural gas. The application also asks the Commission to predetermine the prudence of replacing OG&E's soon-to-be retired Mustang steam turbines in late 2017 (approximately 460 MW) with 400 MW of new, efficient combustion turbines at the Mustang site in 2018 and 2019 and approval for a recovery mechanism for the associated costs. OG&E estimates the total capital cost associated with its environmental compliance and Mustang modernization plans included in this application to be approximately $1.1 billion. The OCC hearing on OG&E's application began on March 3, 2015 and concluded on April 8, 2015. Multiple parties advocating a variety of positions have intervened in the proceeding. OG&E expects a ruling from the OCC in the second or third quarter of 2015. At this time, OG&E cannot predict the outcome of the proceeding. OG&E plans to file applications in the second quarter of 2015 seeking related approvals from the APSC. Oklahoma Demand Program Rider Review In July 2012, OG&E filed an application with the OCC to recover certain costs associated with Demand Programs through the Demand Program Rider, including the lost revenues associated with the SmartHours program. The SmartHours program is designed to incentivize participating customers to reduce on-peak usage or shift usage to off peak hours during the months of May through October, by offering lower rates to those customers in the off peak hours of those months. Lost revenues are created by the difference in the standard rates and the lower incentivized rates. Non SmartHours program customers benefit from the reduction of on-peak usage by SmartHours customers, by the reduction of more costly on-peak generation and the delay in adding new on-peak generation. In December 2012, the OCC issued an order approving the recovery of costs associated with the Demand Programs, including the lost revenues associated with the SmartHours program, subject to the Oklahoma Public Utility Division staff review. In March 2014, the Oklahoma Public Utility Division staff began their review of the Demand Program cost, including the lost revenues associated with the SmartHours program. In November 2014, OG&E believed that it had reached an agreement with the Oklahoma Public Utility Division staff on the methodology to be used to calculate lost revenues associated with the SmartHours program and the amount of lost revenue for 2013, which totaled $10.1 million. The agreement also included utilizing the same methodology for calculating lost revenues for 2014, which would result in lost revenues for 2014 of $11.6 million. In January 2015, OG&E implemented rates that began recovering the 2013 lost revenues, in accordance with the agreement that it believed had been reached with the Oklahoma Public Utility Division staff. In April 2015, the Oklahoma Public Utility Division staff filed an application, seeking an order from the OCC determining the proper calculation methodology for lost revenues pursuant to OG&E’s Demand Program Rider, primarily affecting the SmartHours program lost revenues. In the application, the Oklahoma Public Utility Division staff recommends the OCC approve the Oklahoma Public Utility Division staff methodology for calculating lost revenues associated with the SmartHours program, which differs from the methodology that OG&E believes it had agreed upon and which would result in recovery of lost revenue for 2013 of only $4.9 million, a reduction of $5.2 million from the amount recorded by OG&E for 2013. OG&E believes that the methodology agreed to in November 2014, is consistent with the 2012 OCC order, and believes that it is probable that it will recover the $10.1 million of lost revenues associated with 2013, and the $11.6 million associated with 2014. A hearing is scheduled to commence on June 30, 2015.

Rate Matters and Regulation

Except as set forth below, the circumstances set forth in Note 15 to the Company's Consolidated Financial Statements included in the Company's 2014 Form 10-K appropriately represent, in all material respects, the current status of the Company's regulatory matters.

Arkansas Regulatory Developments

The State of Arkansas recently enacted two laws related to rate filings. Act 725, among other things, provides a public utility the option, to be exercised concurrently with the filing of a general rate application, to file notice of its intent to exercise its right for an annual formula rate review so as to provide a streamlined review of the utility’s rates to determine if adjustments in rates are justified. If the utility exercises such rights, rates may be adjusted if the earned return rate is 0.5 percent above or below the target return rate. This procedure is expected to reduce regulatory lag in Arkansas. Act 725 additionally allows for evidence to be presented, relative to the calculation of the return on common equity, comparing the requested return on common equity to approved returns on common equity for public utilities delivering similar services with corresponding risks within Arkansas and also in similar regulatory jurisdictions in the same general part of the country.

Act 1000 amends and clarifies existing interim rate requirements to expand the types of expenses that may be recorded and specifically authorize the recovery of allowance for funds used during construction. Act 1000 allows a public utility to file for an interim rate schedule through which it may recover investments and expenses, including allowance for funds used during construction, expended complying with legislative or administrative rules, regulations, or requirements related to the protection of the public, health, safety, or the environment. Rates are implemented at the time of filing of the interim rate schedule, subject to refund.

Pending Regulatory Matters

Environmental Compliance Plan

On August 6, 2014, OG&E filed an application with the OCC for approval of its plan to comply with EPA’s MATS and Regional Haze FIP while serving the best long-term interests of customers in light of future environmental uncertainties. The application seeks approval of the environmental compliance plan and for a recovery mechanism for the associated costs. The environmental compliance plan includes installing dry scrubbers at Sooner Units 1 and 2 and the conversion of Muskogee Units 4 and 5 to natural gas. The application also asks the Commission to predetermine the prudence of replacing OG&E's soon-to-be retired Mustang steam turbines in late 2017 (approximately 460 MW) with 400 MW of new, efficient combustion turbines at the Mustang site in 2018 and 2019 and approval for a recovery mechanism for the associated costs. OG&E estimates the total capital cost associated with its environmental compliance and Mustang modernization plans included in this application to be approximately $1.1 billion. The OCC hearing on OG&E's application began on March 3, 2015 and concluded on April 8, 2015. Multiple parties advocating a variety of positions have intervened in the proceeding. OG&E expects a ruling from the OCC in the second or third quarter of 2015. At this time, OG&E cannot predict the outcome of the proceeding. OG&E plans to file applications in the second quarter of 2015 seeking related approvals from the APSC.

Oklahoma Demand Program Rider Review

In July 2012, OG&E filed an application with the OCC to recover certain costs associated with Demand Programs through the Demand Program Rider, including the lost revenues associated with the SmartHours program. The SmartHours program is designed to incentivize participating customers to reduce on-peak usage or shift usage to off peak hours during the months of May through October, by offering lower rates to those customers in the off peak hours of those months. Lost revenues are created by the difference in the standard rates and the lower incentivized rates. Non SmartHours program customers benefit from the reduction of on-peak usage by SmartHours customers, by the reduction of more costly on-peak generation and the delay in adding new on-peak generation.

In December 2012, the OCC issued an order approving the recovery of costs associated with the Demand Programs, including the lost revenues associated with the SmartHours program, subject to the Oklahoma Public Utility Division staff review.

In March 2014, the Oklahoma Public Utility Division staff began their review of the Demand Program cost, including the lost revenues associated with the SmartHours program. In November 2014, OG&E believed that it had reached an agreement with the Oklahoma Public Utility Division staff on the methodology to be used to calculate lost revenues associated with the SmartHours program and the amount of lost revenue for 2013, which totaled $10.1 million. The agreement also included utilizing the same methodology for calculating lost revenues for 2014, which would result in lost revenues for 2014 of $11.6 million.

In January 2015, OG&E implemented rates that began recovering the 2013 lost revenues, in accordance with the agreement that it believed had been reached with the Oklahoma Public Utility Division staff.

In April 2015, the Oklahoma Public Utility Division staff filed an application, seeking an order from the OCC determining the proper calculation methodology for lost revenues pursuant to OG&E’s Demand Program Rider, primarily affecting the SmartHours program lost revenues. In the application, the Oklahoma Public Utility Division staff recommends the OCC approve the Oklahoma Public Utility Division staff methodology for calculating lost revenues associated with the SmartHours program, which differs from the methodology that OG&E believes it had agreed upon and which would result in recovery of lost revenue for 2013 of only $4.9 million, a reduction of $5.2 million from the amount recorded by OG&E for 2013.

OG&E believes that the methodology agreed to in November 2014, is consistent with the 2012 OCC order, and believes that it is probable that it will recover the $10.1 million of lost revenues associated with 2013, and the $11.6 million associated with 2014. A hearing is scheduled to commence on June 30, 2015.