Rate Matters and Regulation	9 Months Ended
Sep. 30, 2014
Regulated Operations [Abstract]
Rate Matters and Regulation	Rate Matters and Regulation Except as set forth below, the circumstances set forth in Note 16 to the Company's Consolidated Financial Statements included in the Company's 2013 Form 10-K appropriately represent, in all material respects, the current status of the Company's regulatory matters. Completed Regulatory Matters Market-Based Rate Authority On June 29, 2012, OG&E filed its triennial market power update with the FERC to retain its market-based rate authorization in the SPP's energy imbalance service market but to surrender its market-based rate authorization for any market-based rates sales outside of the SPP's energy imbalance service market. On May 2, 2013, the FERC issued an order accepting OG&E's June 2012 triennial market power update. On December 30, 2013, OG&E submitted to the FERC a market-based rate change in status filing and a revised market-based rate tariff that would authorize OG&E to (i) sell electric energy and capacity at market-based rates without geographic restriction, and (ii) sell ancillary services in the SPP and Midcontinent Independent System Operator, Inc. markets. The primary goal of this filing was to implement the market-based rate authority OG&E needs to fully participate in SPP’s Integrated Marketplace. On February 28, 2014, FERC issued a letter order accepting OG&E’s market-based rate filing and tariff effective March 1, 2014. FERC found that OG&E passed the market power screens and satisfied requirements related to horizontal market power and vertical market power. Section 206 Complaint On November 26, 2013, Arkansas Electric Cooperative Corporation filed a complaint at the FERC against OG&E, arguing that the wholesale formula rate contract between OG&E and Arkansas Electric Cooperative Corporation (formerly between OG&E and Arkansas Valley Electric Cooperative) is unjust and unreasonable with respect to several items. OG&E and Arkansas Electric Cooperative Corporation agreed to terms of a settlement and filed the offer of settlement with the FERC on February 24, 2014. On April 17, 2014, the FERC accepted the settlement making it effective as of March 1, 2014. OG&E believes the reduction in revenue will be approximately $1.0 million per year for the term of the agreement, which ends June 30, 2015. Fuel Adjustment Clause Review for Calendar Year 2012 The OCC routinely reviews the costs recovered from customers through OG&E's fuel adjustment clause. On July 31, 2013, the OCC Staff filed an application to review OG&E's fuel adjustment clause for calendar year 2012, including the prudence of OG&E's electric generation, purchased power and fuel procurement costs. OG&E filed the necessary information and documents needed to satisfy the OCC's minimum filing requirement rules on October 9, 2013. On April 24, 2014, the OCC administrative law judge at the hearing, on the merits, recommended that the OCC find that OG&E's 2012 electric generation, purchased power and fuel procurement processes and costs were prudent. On June 10, 2014, the OCC issued an order approving OG&E’s practices, policies and judgment regarding its electric generation, purchased power, and fuel procurement processes and costs for the calendar year 2012. The order also found that the costs were prudent, reasonable, and mathematically correct. Pending Regulatory Matters Energy Efficiency Program Filing On February 14, 2014, OG&E filed an application with the APSC requesting approval of interim modifications to approved Energy Efficiency Programs, new tariff revisions and the waiver of certain provisions of the Commission’s Rules for Conservation and Energy Efficiency Programs. Integrated Resource Plans In June 2014, OG&E initiated the process to update its Integrated Resource Plans in Oklahoma and Arkansas. The Commissions’ rules provide for an update of OG&E’s triennial plan in the event of a significant change in the underlying assumptions used in the previous plan. The current Integrated Resource Plan, submitted in 2012, assumed that the Oklahoma SIP would be followed to comply with Regional Haze requirements. Subsequent to holding technical conferences and public stakeholder meetings, OG&E submitted its revised Integrated Resource Plans to the OCC on August 4, 2014 and to the APSC on September 8, 2014. 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 costs of compliance with MATS and Regional Haze to be approximately $1.1 billion. The OCC hearing on OG&E's application is scheduled for March 2015. OG&E plans to file applications in the fourth quarter of 2014 seeking related approvals from the APSC. More detail regarding planned capital expenditures for environmental compliance can be found within the table presented under the "Capital Expenditures" section of "Management's Discussion and Analysis of Financial Condition and Results of Operations" of Part I, Item 2 of this Form 10-Q. Fuel Adjustment Clause Review for Calendar Year 2013 The OCC routinely reviews the costs recovered from customers through OG&E's fuel adjustment clause. On July 31, 2014, the OCC Staff filed an application to review OG&E's fuel adjustment clause for calendar year 2013, including the prudence of OG&E's electric generation, purchased power and fuel procurement costs. OG&E filed the necessary information and documents needed to satisfy the OCC's minimum filing requirement rules on September 29, 2014. A procedural schedule has not been established as of this date. OG&E expects an order in the second quarter of 2015.

Rate Matters and Regulation

Except as set forth below, the circumstances set forth in Note 16 to the Company's Consolidated Financial Statements included in the Company's 2013 Form 10-K appropriately represent, in all material respects, the current status of the Company's regulatory matters.

Completed Regulatory Matters

Market-Based Rate Authority

On June 29, 2012, OG&E filed its triennial market power update with the FERC to retain its market-based rate authorization in the SPP's energy imbalance service market but to surrender its market-based rate authorization for any market-based rates sales outside of the SPP's energy imbalance service market. On May 2, 2013, the FERC issued an order accepting OG&E's June 2012 triennial market power update.

On December 30, 2013, OG&E submitted to the FERC a market-based rate change in status filing and a revised market-based rate tariff that would authorize OG&E to (i) sell electric energy and capacity at market-based rates without geographic restriction, and (ii) sell ancillary services in the SPP and Midcontinent Independent System Operator, Inc. markets. The primary goal of this filing was to implement the market-based rate authority OG&E needs to fully participate in SPP’s Integrated Marketplace. On February 28, 2014, FERC issued a letter order accepting OG&E’s market-based rate filing and tariff effective March 1, 2014. FERC found that OG&E passed the market power screens and satisfied requirements related to horizontal market power and vertical market power.

Section 206 Complaint

On November 26, 2013, Arkansas Electric Cooperative Corporation filed a complaint at the FERC against OG&E, arguing that the wholesale formula rate contract between OG&E and Arkansas Electric Cooperative Corporation (formerly between OG&E and Arkansas Valley Electric Cooperative) is unjust and unreasonable with respect to several items. OG&E and Arkansas Electric Cooperative Corporation agreed to terms of a settlement and filed the offer of settlement with the FERC on February 24, 2014. On April 17, 2014, the FERC accepted the settlement making it effective as of March 1, 2014. OG&E believes the reduction in revenue will be approximately $1.0 million per year for the term of the agreement, which ends June 30, 2015.

Fuel Adjustment Clause Review for Calendar Year 2012

The OCC routinely reviews the costs recovered from customers through OG&E's fuel adjustment clause. On July 31, 2013, the OCC Staff filed an application to review OG&E's fuel adjustment clause for calendar year 2012, including the prudence of OG&E's electric generation, purchased power and fuel procurement costs. OG&E filed the necessary information and documents needed to satisfy the OCC's minimum filing requirement rules on October 9, 2013. On April 24, 2014, the OCC administrative law judge at the hearing, on the merits, recommended that the OCC find that OG&E's 2012 electric generation, purchased power and fuel procurement processes and costs were prudent. On June 10, 2014, the OCC issued an order approving OG&E’s practices, policies and judgment regarding its electric generation, purchased power, and fuel procurement processes and costs for the calendar year 2012. The order also found that the costs were prudent, reasonable, and mathematically correct.

Pending Regulatory Matters

Energy Efficiency Program Filing

On February 14, 2014, OG&E filed an application with the APSC requesting approval of interim modifications to approved Energy Efficiency Programs, new tariff revisions and the waiver of certain provisions of the Commission’s Rules for Conservation and Energy Efficiency Programs.

Integrated Resource Plans

In June 2014, OG&E initiated the process to update its Integrated Resource Plans in Oklahoma and Arkansas. The Commissions’ rules provide for an update of OG&E’s triennial plan in the event of a significant change in the underlying assumptions used in the previous plan. The current Integrated Resource Plan, submitted in 2012, assumed that the Oklahoma SIP would be followed to comply with Regional Haze requirements. Subsequent to holding technical conferences and public stakeholder meetings, OG&E submitted its revised Integrated Resource Plans to the OCC on August 4, 2014 and to the APSC on September 8, 2014.

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 costs of compliance with MATS and Regional Haze to be approximately $1.1 billion. The OCC hearing on OG&E's application is scheduled for March 2015. OG&E plans to file applications in the fourth quarter of 2014 seeking related approvals from the APSC. More detail regarding planned capital expenditures for environmental compliance can be found within the table presented under the "Capital Expenditures" section of "Management's Discussion and Analysis of Financial Condition and Results of Operations" of Part I, Item 2 of this Form 10-Q.

Fuel Adjustment Clause Review for Calendar Year 2013

The OCC routinely reviews the costs recovered from customers through OG&E's fuel adjustment clause. On July 31, 2014, the OCC Staff filed an application to review OG&E's fuel adjustment clause for calendar year 2013, including the prudence of OG&E's electric generation, purchased power and fuel procurement costs. OG&E filed the necessary information and documents needed to satisfy the OCC's minimum filing requirement rules on September 29, 2014. A procedural schedule has not been established as of this date. OG&E expects an order in the second quarter of 2015.