Accounting Policies [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Domain] Adjustments for New Accounting Pronouncements [Domain] Adjustments for New Accounting Pronouncements [Domain] Reclassified Shares Withheld for Employee Taxes [Member] Reclassified Shares Withheld for Employee Taxes [Member] Reclassified Shares Withheld for Employee Taxes [Member] Cumulative Effect of Net Deferred Taxes [Member] Cumulative Effect of Net Deferred Taxes [Member] Cumulative Effect of Net Deferred Taxes [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification Fuel Inventories [Abstract] Fuel Inventories [Abstract] Statement [Table] Statement [Table] Enable Gas Transportation and Storage Agreement [Axis] Enable Gas Transportation and Storage Agreement [Axis] Enable Gas Transportation and Storage Agreement [Axis] Enable Gas Transportation and Storage Agreement [Domain] Enable Gas Transportation and Storage Agreement [Domain] [Domain] for Enable Gas Transportation and Storage Agreement [Axis] Enable Gas Transportation and Storage Agreement [Member] Enable Gas Transportation and Storage Agreement [Member] Enable Gas Transportation and Storage Agreement [Member] Inventory [Axis] Inventory [Axis] Inventory [Domain] Inventory [Domain] Public Utilities, Inventory, Fuel [Member] Public Utilities, Inventory, Fuel [Member] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] OG&E [Member] Og and E [Member] Og and E [Member] Enogex [Member] Enogex [Member] Enogex [Member] Statement [Line Items] Statement [Line Items] Public Utilities, Inventory Public Utilities, Inventory Other Assets Deferred Costs and Other Assets Other Other Assets, Current Equity Method Investments and Joint Ventures [Abstract] Operating revenues Equity Method Investment, Summarized Financial Information, Revenue Cost of natural gas and NGLs Equity Method Investment, Summarized Financial Information, Cost of Sales Operating income (loss) Equity Method Investment, Summarized Financial Information, Operating Income Equity Method Investment, Summarized Financial Information, Operating Income Net income (loss) Equity Method Investment, Summarized Financial Information, Net Income (Loss) Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Natural Gas Midstream Operations [Member] Natural Gas Midstream Operations [Member] Midstream Operations [Member] Legal Entity of Counterparty, Type [Axis] Legal Entity of Counterparty, Type [Axis] Legal Entity Type of Counterparty [Domain] Legal Entity Type of Counterparty [Domain] Natural Gas Transportation [Member] Natural Gas Transportation [Member] Natural Gas Transportation [Member] Operating Costs Charged [Member] Operating Costs Charged [Member] Operating Costs Charged [Member] Natural Gas Storage [Member] Natural Gas Storage [Member] Natural Gas Storage [Member] Natural Gas Purchases [Member] Natural Gas Purchases [Member] Natural Gas Purchases [Member] Enable Midstream Partners [Member] Enable Midstream Partners [Member] Enable Midstream Partners [Member] Enogex LLC [Member] Enogex LLC [Member] Enogex LLC [Member] Og and E [Member] Southeast Supply Header, LLC [Member] Southeast Supply Header, LLC [Member] Southeast Supply Header, LLC [Member] ArcLight group [Member] ArcLight group [Member] ArcLight Group [Member] OGE Holdings [Member] OGE Holdings [Member] OGE Holdings [Member] OGE Energy [Member] OGE Energy [Member] OGE Energy [Member] CenterPoint [Member] CenterPoint [Member] CenterPoint [Member] Investment, Name [Axis] Investment, Name [Axis] Investment, Name [Domain] Investment, Name [Domain] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Accounts receivable - unconsolidated affiliates Accounts Receivable, Related Parties, Current Goodwill, Impairment Loss Goodwill, Impairment Loss Percentage of Enogex LLC Contributed Percentage of Enogex LLC Contributed Percentage of Enogex LLC Contributed Contributions to Pay Down Short-Term Debt Contributions to Pay Down Short-Term Debt Contributions to Pay Down Short-Term Debt Percentage Share of Management Rights Percentage Share of Management Rights Percentage Share of Management Rights Partners' Capital Account, Units, Sold in Public Offering Partners' Capital Account, Units, Sold in Public Offering Limited Partner Units Owned Limited Partner Units Owned Limited Partner Units Owned Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest Subordinated Units Held by Limited Partners of the LLC or LP Subordinated Units Held by Limited Partners of the LLC or LP The number of subordinated units held by one or more members or limited partners of the LLC or LP. Distribution Made to Limited Partner, Distributions Declared, Per Unit Distribution Made to Limited Partner, Distributions Declared, Per Unit Proceeds from Issuance Initial Public Offering Proceeds from Issuance Initial Public Offering Percentage of Subsidiary Contributed percentage of subsidiary contributed percentage of subsidiary contributed Partners' Capital Account, Units, Acquisitions Partners' Capital Account, Units, Acquisitions Percent of Incentive Distribution Rights Percent of Incentive Distribution Rights Percent of Incentive Distribution Rights Distributions received Proceeds from Equity Method Investment, Distribution Increase in fair value of net assets Increase in Fair Value of Net Assets Increase in Fair Value of Net Assets Equity Method Investment, Difference Between Carrying Amount and Underlying Equity Equity Method Investment, Difference Between Carrying Amount and Underlying Equity Equity in earnings of unconsolidated affiliates Income (Loss) from Equity Method Investments Regulated Operations [Abstract] Rate Matters and Regulation Rate Matters And Regulation [Text Block] Describes all of the specific events that have or may impact rates and amortization of regulatory assets and liabilities (for example, pending or recently concluded regulatory proceedings). Specifics may include quantifications related to rates, costs, and earnings. Events may relate to rate moratoriums or price tags. Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Supplemental Cash Flow Information [Abstract] Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Retirement Plans and Postretirement Benefit Plans [Abstract] Pension and Other Postretirement Benefits Disclosure [Text Block] Pension and Other Postretirement Benefits Disclosure [Text Block] STATEMENTS OF CAPITALIZATION [Abstract] STATEMENTS OF CAPITALIZATION [Abstract] Schedule of Capitalization [Table] Schedule of Capitalization [Table] Schedule of Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Axis] Schedule of Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Axis] Financial Instruments Subject to Mandatory Redemption, Financial Instrument [Domain] Financial Instruments Subject to Mandatory Redemption, Financial Instrument [Domain] Debentures Subject to Mandatory Redemption [Member] Debentures Subject to Mandatory Redemption [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Senior Notes [Member] Senior Notes [Member] Long-term Debt [Member] Long-term Debt [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Series Due November 15, 2014 [Member] Series Due November 15, 2014 [Member] Series Due November 15, 2014 [Member] Series Due November 24, 2017 [Member] Series Due November 24, 2017 [Member] Series Due November 24, 2017 [Member] Series Due January 15, 2016 [Member] Series Due January 15, 2016 [Member] Series Due January 15, 2016 [Member] Series Due July 15, 2017 [Member] Series Due July 15, 2017 [Member] Series Due July 15, 2017 [Member] Series Due September 1, 2018 [Member] Series Due September 1, 2018 [Member] Series Due September 1, 2018 [Member] Series Due January 15, 2019 [Member] Series Due January 15, 2019 [Member] Series Due January 15, 2019 [Member] Series Due July 15, 2027 [Member] Series Due July 15, 2027 [Member] Series Due July 15, 2027 [Member] Series Due April 15, 2028 [Member] Series Due April 15, 2028 [Member] Series Due April 15, 2028 [Member] Series Due August 1, 2034 [Member] Series Due August 1, 2034 [Member] Series Due August 1, 2034 [Member] Series Due January 15, 2036 [Member] Series Due January 15, 2036 [Member] Series Due January 15, 2036 [Member] Series Due February 1, 2038 [Member] Series Due February 1, 2038 [Member] Series Due February 1, 2038 [Member] Series Due June 1, 2040 [Member] Series Due June 1, 2040 [Member] Series Due June 1, 2040 [Member] Series Due May 15, 2041 [Member] Senior Notes due May 15, 2041 [Member] Senior Notes due May 15, 2041 [Member] Series Due May 1, 2043 [Member] Series due May 1, 2043 [Member] Series due May 1, 2043 [Member] Series Due March 15, 2044 [Member] Series due March 15, 2044 [Member] Series due March 15, 2044 [Member] Series Due December 15, 2044 [Member] Series due December 15, 2044 [Member] Series due December 15, 2044 [Member] Series due August 15, 2047 [Member] [Domain] Series due August 15, 2047 [Member] [Domain] Series due August 15, 2047 [Member] [Domain] Series due April 1, 2047 [Member] Series due April 1, 2047 [Member] Series due April 1, 2047 [Member] Due August 31, 2062 [Member] Due August 31, 2062 [Member] Due August 31, 2062 Garfield Industrial Authority Bond [Member] Garfield Industrial Authority Bond [Member] Garfield Industrial Authority Bond [Member] Muskogee Industrial Authority Bond Due 2025 [Member] Muskogee Industrial Authority Bond Due 2025 [Member] Muskogee Industrial Authority Bond Due 2025 [Member] Muskogee Industrial Authority Bond Due 2027 [Member] Muskogee Industrial Authority Bond Due 2027 [Member] Muskogee Industrial Authority Bond Due 2027 [Member] Schedule of Capitalization, Long-term Debt [Line Items] Schedule of Capitalization, Long-term Debt [Line Items] Common stock, par value $0.01 per share; authorized 450.0 shares; and outstanding 199.7 shares and 199.7 shares, respectively Common Stock, Value, Issued Premium on common stock Additional Paid in Capital, Common Stock Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss, net of tax Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders' equity Stockholders' Equity Attributable to Parent Long-term Debt, Gross Long-term Debt, Gross Unamortized debt expense Unamortized Debt Issuance Expense Unamortized discount Debt Instrument, Unamortized Discount Debt Instrument, Interest Rate, Stated Percentage Debt Instrument, Interest Rate, Stated Percentage Total long-term debt Long-term Debt Less: long-term debt due within one year Long-term Debt, Current Maturities Total long-term debt (excluding debt due within one year) Long-term Debt, Excluding Current Maturities Total capitalization (including long-term debt due within one year) Capitalization, Long-term Debt and Equity Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Unrecorded Unconditional Purchase Obligations Disclosure [Table Text Block] Unrecorded Unconditional Purchase Obligations Disclosure [Table Text Block] Schedule of Wind Power Purchases [Table Text Block] Schedule of Wind Power Purchases [Table Text Block] Schedule of Wind Power Purchases [Table Text Block] Income Taxes [Abstract] Income Taxes [Abstract] OGE Energy Corp. [Member] OGE Energy Corp. [Member] OGE Energy Corp. [Member] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] State and Local Jurisdiction [Member] State and Local Jurisdiction [Member] Federal operating loss [Member] Federal operating loss [Member] Federal operating loss [Member] Tax Credit Carryforward [Axis] Tax Credit Carryforward [Axis] Tax Credit Carryforward, Name [Domain] Tax Credit Carryforward, Name [Domain] State operating loss [Member] State operating loss [Member] State operating loss [Member] Federal operating loss [Member] Federal operating loss [Member] [Member] Federal operating loss [Member] [Member] Federal tax credits [Member] Federal tax credits [Member] [Member] Federal tax credits [Member] [Member] Oklahoma investment tax credits [Member] Oklahoma investment tax credits [Member] [Member] Oklahoma investment tax credits [Member] [Member] Oklahoma capital investment board credits [Member] Oklahoma capital investment board credits [Member] [Member] Oklahoma capital investment board credits [Member] [Member] Oklahoma zero emission tax credits [Member] Oklahoma zero emission tax credits [Member] [Member] Oklahoma zero emission tax credits [Member] [Member] Louisiana inventory credits [Member] [Member] [Domain] Louisiana inventory credits [Member] [Member] [Domain] Louisiana inventory credits [Member] [Member] [Domain] Reduction in net deferred income tax liability Reduction in net deferred income tax liability Reduction in net deferred income tax liability Operating Loss Carryforwards Operating Loss Carryforwards Deferred Tax Assets, Operating Loss Carryforwards, State and Local Deferred Tax Assets, Operating Loss Carryforwards, State and Local Current Federal Tax Expense (Benefit) Current Federal Tax Expense (Benefit) Current State and Local Tax Expense (Benefit) Current State and Local Tax Expense (Benefit) Current Income Tax Expense (Benefit) Current Income Tax Expense (Benefit) Deferred Federal Income Tax Expense (Benefit) Deferred Federal Income Tax Expense (Benefit) Deferred State and Local Income Tax Expense (Benefit) Deferred State and Local Income Tax Expense (Benefit) Deferred Income Tax Expense (Benefit) Deferred Income Tax Expense (Benefit) Investment Tax Credit Investment Tax Credit Income Tax Expense (Benefit) Income Tax Expense (Benefit) Statutory federal tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Federal deferred tax revaluation Federal tax percentage revaluation Federal tax percentage revaluation Federal renewable energy credit (A) Effective Income Tax Rate Reconciliation, Tax Credit, Other, Percent Remeasurement of state deferred tax liabilities Effective Income Tax Rate Reconciliation, Change in Deferred Tax Liabilities Valuation Allowance, Percent Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax liabilities. 401(k) dividends Effective Income Tax Rate Reconciliation, Deduction, Employee Stock Ownership Plan Dividend, Percent Federal investment tax credits, net Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Percent State income taxes, net of federal income tax benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Uncertain tax positions Effective Income Tax Rate Reconciliation, Tax Contingency, Percent Amortization of net unfunded deferred taxes Effective Income Tax Rate Reconciliation Amortization of Net Unfunded Deferred Taxes Effective Income Tax Rate Reconciliation Amortization of Net Unfunded Deferred Taxes Other Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Net operating losses Deferred Tax Assets, Operating Loss Carryforwards Accrued liabilities Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Federal tax credits Current Deferred Tax Assets, Federal Tax Credits Current Deferred Tax Assets, Federal Tax Credits Accrued vacation Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Other Uncollectible accounts Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Allowance for Doubtful Accounts Total Current Deferred Income Tax Assets Deferred Tax Assets, Gross, Current Accelerated depreciation and other property related differences Deferred Tax Liabilities, Property, Plant and Equipment Investment in Enable Midstream Partners Non-Current Deferred Tax Liabilities, Investment in Enable Midstream Partners Non-Current Deferred Tax Liabilities, Investment in Enable Midstream Partners Regulatory asset Deferred Tax Liabilities, Regulatory Assets Income taxes (recoverable from) refundable to customers, net Deferred Tax Liabilities, Income Taxes Refundable to Customers, Net Deferred Tax Liabilities, Income Taxes Refundable to Customers, Net Company Pension Plan Deferred Tax Liabilities, Prepaid Expenses Bond redemption-unamortized costs Deferred Tax Liabilities, Unamortized Bond Redemption Costs Deferred Tax Liabilities, Unamortized Bond Redemption Costs Derivative instruments Deferred Tax Liabilities, Derivatives Total deferred income tax liabilities Deferred Tax Liabilities, Gross, Noncurrent Federal tax credits Deferred Tax Assets, Tax Credit Carryforwards State tax credits Non-Current Deferred Tax Assets, State Tax Credits Non-Current Deferred Tax Assets, State Tax Credits Postretirement medical and life insurance benefits Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Net operating losses Non-Current Deferred Tax Asset, Net Operating Losses Non-Current Deferred Tax Asset, Net Operating Losses Regulatory liabilities Non-Current Deferred Tax Assets, Regulatory Liabilities Non-Current Deferred Tax Assets, Regulatory Liabilities Asset retirement obligations Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Asset Retirement Obligations Deferred federal investment tax credits Non-Current Deferred Tax Assets, Deferred Federal Investment Tax Credits Non-Current Deferred Tax Assets, Deferred Federal Investment Tax Credits Other Deferred Tax Assets, Other Total Non-Current Deferred Income Tax Assets Deferred Tax Assets, Gross, Noncurrent Total deferred income tax liabilities, net Deferred Tax Liabilities, Net, Noncurrent Unrecognized Tax Benefits Unrecognized Tax Benefits that Would Impact Effective Tax Rate Unrecognized Tax Benefits Unrecognized Tax Benefits Current year additions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Prior year additions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Unrecognized Tax Benefits, Period Increase (Decrease) Unrecognized Tax Benefits, Period Increase (Decrease) Tax Credit Carryforward, Amount Tax Credit Carryforward, Amount Tax Credit Carryforward, Deferred Tax Asset Tax Credit Carryforward, Expiration Date Tax Credit Carryforward, Expiration Date Employee Service Share-based Compensation, Unrecognized Tax Benefit from Compensation Expense Employee Service Share-based Compensation, Unrecognized Tax Benefit from Compensation Expense The total tax benefit to be recognized in future periods related to compensation cost for equity-based payment arrangements. Reduction in income tax expense Reduction in income tax expense reduction in income tax expense Increased Regulatory Liabilities due to Income Taxes Increased Regulatory Liabilities due to Income Taxes Increased Regulatory Liabilities due to Income Taxes Stock-Based Compensation [Abstract] Stock-Based Compensation [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Share Based Compensation, Shares Issued, Returned and Cash Recieved from Exercise [Axis] Share Based Compensation, Shares Issued, Returned and Cash Recieved from Exercise [Axis] Share Based Compensation, Shares Issued, Returned and Cash Recieved from Exercise [Axis] Shares Issued, Returned and Cash Recieved from Exercise [Domain] Shares Issued, Returned and Cash Recieved from Exercise [Domain] Shares Issued, Returned and Cash Recieved from Exercise [Domain] Common Stock [Member] Common Stock 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Attributable to Unconsolidated Affiliates Amount Attributable to Unconsolidated Affiliates Compensation Expense, Net of Unconsolidated Affiliates Allocated Share-Based Compensation Expense, Net of Unconsolidated Affiliates Allocated Share-Based Compensation Expense, Net of Unconsolidated Affiliates Tax Benefit from Compensation Expense Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Shares Paid for Tax Withholding Shares Paid for Tax Withholding for Share Based Compensation Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Share-based 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Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Settlement Cost, before Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Settlement Cost, before Tax Amount before tax of reclassification adjustment from accumulated other comprehensive (income) loss related to the settlement charge for pension and other postretirement defined benefit plans. 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Components of Net Periodic Benefit Costs to be Recognized in Next Fiscal Year Components of Net Periodic Benefit Costs to be Recognized in Next Fiscal Year Statement of Financial Position [Abstract] Statement, Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Allowance for Doubtful Accounts Receivable Allowance for Doubtful Accounts Receivable Organization, Consolidation and Presentation of Financial Statements [Abstract] Consolidation, Policy [Policy Text Block] Consolidation, Policy [Policy Text Block] Basis of Accounting, Policy [Policy Text Block] Basis of Accounting, Policy [Policy Text Block] Public Utilities, Policy [Policy Text Block] Public Utilities, Policy [Policy Text Block] Use of Estimates, Policy [Policy Text Block] Use of Estimates, Policy [Policy Text Block] Cash and Cash Equivalents, Policy [Policy Text Block] Cash and Cash Equivalents, Policy [Policy Text Block] Allowance for Uncollectible Accounts Receivable, Policy Trade and Other Accounts Receivable, Policy [Policy Text Block] Inventory, Policy [Policy Text Block] Inventory, Policy [Policy Text Block] Property, Plant and Equipment, Policy [Policy Text Block] Property, Plant and Equipment, Policy [Policy Text Block] Depreciation and Amortization, Policy [Policy Text Block] Depreciation, Depletion, and Amortization [Policy Text Block] Equity Method Investments [Policy Text Block] Equity Method Investments [Policy Text Block] Asset Retirement Obligation [Policy Text Block] Asset Retirement Obligation [Policy Text Block] Allowance for Funds Used During Construction, Policy [Policy Text Block] Allowance for Funds Used During Construction, Policy [Policy Text Block] Collection of Sales Tax, Policy [Policy Text Block] Collection of sales tax policy [Policy Text Block] Collection of sales tax policy [Policy Text Block] Revenue Recognition, Policy [Policy Text Block] Revenue Recognition, Policy [Policy Text Block] Fuel Adjustment Clauses, Policy [Policy Text 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[Policy Text Block] Plan Investments, Policies and Strategies, Policy [Policy Text Block] Plan Investments, Policies and Strategies [Policy Text Block] Plan Investments, Policies and Strategies [Policy Text Block] Pension and Other Postretirement Plans, Nonpension Benefits, Policy [Policy Text Block] Pension and Other Postretirement Plans, Nonpension Benefits, Policy [Policy Text Block] Reclassifications [Text Block] Reclassification, Policy [Policy Text Block] Equity [Abstract] Automatic Dividend Reinvestment and Stock Purchase Plan [Member] Automatic Dividend Reinvestment and Stock Purchase Plan [Member] Automatic Dividend Reinvestment and Stock Purchase Plan [Member] Stock Issued During Period, Shares, Dividend Reinvestment Plan and Stock Purchase Plan Stock Issued During Period, Shares, New Issues Proceeds From Issuance of Shares Under Dividend Reinvestment Plan And Stock Purchase Plan Stock Issued During Period, Value, New Issues Shares Held in Reserve Related to Dividend Reinvestment Plan and Stock Purchase Plan Common Stock, Capital Shares Reserved for Future Issuance Schedule of Regulatory Assets and Liabilities [Table] Schedule of Regulatory Assets and Liabilities [Table] Schedule of Regulatory Assets and Liabilities [Table] Smart Grid Capital Costs [Axis] Smart Grid Capital Costs [Axis] Smart Grid Capital Costs [Axis] Smart Grid Capital Costs [Domain] Smart Grid Capital Costs [Domain] Smart Grid Capital Costs [Domain] Smart Grid Project [Member] Smart Grid Project [Member] Smart Grid Project [Member] Regulatory Asset [Axis] Regulatory Asset [Axis] Regulatory Asset [Domain] Regulatory Asset [Domain] Oklahoma demand program rider under recovery [Member] Oklahoma demand program rider under recovery [Member] Oklahoma demand program rider under recovery[Member] SPP cost tracker under recovery [Member] SPP Cost Tracker Rider Under Recovery [Member] SPP Cost Tracker Rider Under Recovery [Member] Crossroads wind farm rider under recovery [Member] Crossroads wind farm rider under recovery [Member] Crossroads wind farm rider under recovery [Member] Other Regulatory Assets [Member] Other Regulatory Assets [Member] Other Regulatory Assets [Member] Benefit obligations regulatory asset [Member] Benefit Obligations [Member] Benefit Obligations [Member] Income taxes recoverable from customers, net [Member] Income taxes recoverable from customers, net [Member] Income taxes recoverable from customers, net [Member] Smart Grid [Member] Smart Grid [Member] Smart Grid [Member] Deferred storm expenses [Member] Deferred storm expenses [Member] Deferred storm expenses [Member] Unamortized loss on reacquired debt [Member] Loss on Reacquired Debt [Member] Pension tracker [Member] Pension tracker [Member] Pension tracker [Member] Regulatory Liability [Axis] Regulatory Liability [Axis] Regulatory Liability [Domain] Regulatory Liability [Domain] Smart Grid rider over recovery [Member] Smart Grid rider over recovery [Member] Smart Grid rider over recovery [Member] Crossroads Wind Farm Rider Over Recovery [Member] Crossroads Wind Farm Rider Over Recovery [Member] Crossroads Wind Farm Rider Over Recovery [Member] Other Regulatory Liabilities [Member] Other Regulatory Liabilities [Member] Other Regulatory Liabilities [Member] Accrued removal obligations [Member] Accrued removal obligations [Member] Accrued removal obligations [Member] Deferred Pension Credit [Member] Deferred Pension Credit [Member] Deferred Pension Credits [Member] Schedule of Regulatory Assets and Liabilities [Line Items] Schedule of Regulatory Assets and Liabilities [Line Items] Schedule of Regulatory Assets and Liabilities [Line Items] Fuel clause under recoveries Deferred Fuel Cost Fuel clause over recoveries Customer Refund Liability, Current Regulatory Assets, Current Regulatory Assets, Current Regulatory Assets, Noncurrent Regulatory Assets, Noncurrent Regulatory Liability, Current Regulatory Liability, Current Regulatory Liability, Noncurrent Regulatory 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Facility Ratio of Consolidated Debt to Consolidated Capitalization Ratio of Consolidated Debt to Consolidated Capitalization The percentage of consolidated debt to total consolidated capitalization, which the entity may not exceed pursuant to a debt covenant. 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Finite-Lived Intangible Assets, Major Class Name [Member] Finite-Lived Intangible Assets, Major Class Name [Member] Finite-Lived Intangible Assets, Major Class Name [Member] Property, Plant and Equipment, Other Types [Member] Property, Plant and Equipment, Other Types [Member] Jointly Owned Utility Plant [Axis] Jointly Owned Utility Plant [Axis] Jointly Owned Utility Plant [Domain] Jointly Owned Utility Plant [Domain] McClain Plant [Member] McClain Plant [Member] McClain Plant [Member] Redbud Plant [Member] Redbud Plant [Member] Redbud Plant [Member] Property, Plant and Equipment [Line Items] Public Utility, Property, Plant and Equipment [Line Items] Jointly Owned Utility Plant, Proportionate Ownership Share Jointly Owned Utility Plant, Proportionate Ownership Share Property, Plant and Equipment, Gross Property, Plant and Equipment, Gross Accumulated Depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Net property, plant and equipment Property, Plant and Equipment, Net Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress Amount of Acquisition Adjustments Public Utilities, Property, Plant and Equipment, Amount of Acquisition Adjustments Public Utilities, Property, Plant and Equipment, Amount of Acquisition Adjustments, Related Accumulated Depreciation Public Utilities, Property, Plant and Equipment, Amount of Acquisition Adjustments, Related Accumulated Depreciation Amount of Acquistion Adjustments Related Accumulated Amortization Amount of Acquistion Adjustments Related Accumulated Amortization The amount of acquisition adjustments accumulated amortization included in property, plant and equipment (PPE) for utilities Capitalized Computer Software, Gross Capitalized Computer Software, Net Capitalized Computer Software, Amortization Capitalized Computer Software, Amortization Allowance for Funds Used During Construction [Abstract] Allowance for Funds Used During Construction [Abstract] Public Utilities, Allowance for Funds Used During Construction, Rate Public Utilities, Allowance for Funds Used During Construction, Rate Allowance for Uncollectible Accounts Receivable [Abstract] Allowance for Uncollectible Accounts Receivable [Abstract] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Summary of Tax Credit Carryforwards [Table Text Block] Summary of Tax Credit Carryforwards [Table 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Equity [Member] International Equity [Member] International Equity [Member] International Equity [Member] Restoration of Retirement Income Plan [Member] Other Pension Plan [Member] Restoration of Retirement Income Plan [Member] Restoration of Retirement Income Plan [Member] Restoration of Retirement Income Plan [Member] Postretirement Benefit Plan [Member] Postretirement Benefit Plan [Member] Postretirement Benefit Plan [Member] Investment Securities Series [Axis] Investment Securities Series [Axis] Investment Securities Class [Domain] Investment Securities Class [Domain] U.S. common stocks [Member] U.S. common stocks [Member] U.S. common stocks [Member] U.S. treasury notes and bonds [Member] US Treasury Securities [Member] Mortgage-backed securities Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Corporate fixed income and other securities [Member] Corporate Debt Securities [Member] Mortgage-backed securities [Member] Collateralized Mortgage Backed Securities [Member] Commingled fund [Member] Equity Funds [Member] Foreign government bonds [Member] Foreign Government Debt Securities [Member] Interest-bearing cash [Member] Interest-bearing Deposits [Member] Municipal bonds [Member] Municipal Bonds [Member] Money market funds [Member] Money Market Funds [Member] Mutual fund [Member] Mutual Fund [Member] Treasury futures, receivable [Member] Treasury futures, receivable [Member] Treasury futures, receivable [Member] Treasury futures, payable [Member] Treasury futures, payable [Member] Treasury futures, payable [Member] Cash collateral [Member] Cash Collateral [Member] Cash Collateral [Member] Receivable (foreign currency) [Member] Receivable (foreign currency) [Member] Forward Contracts Receivable [Member] Payable (foreign currency) [Member] Payable (foreign currency) [Member] Forward Contracts Payable [Member] Index fund [Member] Index Fund [Member] Index Fund [Member] Preferred stocks (foreign) [Member] Preferred Stock [Member] Total Plan investments [Member] Total Plan investments [Member] Total Plan Investments [Member] Receivable from broker for securities sold [Member] Receivable from broker for securities sold [Member] Receivable From Broker For Securities Sold [Member] Interest and dividends receivable [Member] Interest and dividends receivable [Member] Interest and Dividends Receivable [Member] Payable to broker for securities purchased [Member] Payable to broker for securities purchased [Member] Payable to Broker for Securities Purchased [Member] Total Plan assets [Member] Total Plan assets [Member] Total Plan assets [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Entity by Location [Axis] Entity by Location [Axis] Location [Domain] Location [Domain] OKLAHOMA OKLAHOMA ARKANSAS ARKANSAS Defined Benefit Plan, Target Allocation Percentage Defined Benefit Plan, Target Allocation Percentage Defined Benefit Plan, Plan Assets, Benefits Paid Defined Benefit Plan, Plan Assets, Benefits Paid Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Defined Benefit Plan, Plan Assets, Payment for Settlement Defined Benefit Plan, Plan Assets, Payment for Settlement Alternative Investment, Fair Value Disclosure Alternative Investment, Fair Value Disclosure Payment for Pension Benefits Payment for Pension Benefits Defined Contribution Plan, Employer Matching Contribution, Percent of Match Defined Contribution Plan, Employer Matching Contribution, Percent of Match Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Accumulated Benefit Obligation Defined Benefit Plan, Accumulated Benefit Obligation Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Benefit Obligation, Beginning Defined Benefit Plan, Benefit Obligation Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Plan curtailments Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment Plan settlements Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement Participants' contributions Defined Benefit Plan, Plan Assets, Contributions by Plan Participant Actuarial gains (losses) Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Benefit Obligation, Ending Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Fair Value of Plan Assets, Beginning Defined Benefit Plan, Fair Value of Plan Assets Actual return on plans' assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer Fair Value of Plan Assets, Ending Funded Status of Plan Defined Benefit Plan, Funded (Unfunded) Status of Plan Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Amortization of transition obligations Defined Benefit Plan, Amortization of Transition Asset (Obligation) Defined Benefit Plan, Amortization of Gain (Loss) Defined Benefit Plan, Amortization of Gain (Loss) Amortization of unrecognized prior service cost Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Curtailment Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment Settlement Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement Net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Net Periodic Benefit Cost, Net of Unconsolidated Affiliates Defined Benefit Plan, Net Periodic Benefit Cost, Net of Unconsolidated Affiliates Defined Benefit Plan, Net Periodic Benefit Cost, Net of Unconsolidated Affiliates Additional Pension Expense to Meet State Requirements Additional Pension Expense to Meet State Requirements Additional Pension Expense to Meet State Requirements Additional Postretirement Medical Expense to Meet State Requirements Additional Postretirement Medical Expense to Meet State Requirements Additional Postretirement Medical Expense to Meet State Requirements Capitalized Portion of Net Periodic Benefit Cost Capitalized Portion of Net Periodic Benefit Cost Capitalized Portion of Net Periodic Benefit Cost Assumptions Used Calculating Benefit Obligation, Discount Rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Health Care Cost Trend Rate Assumed for Next Fiscal Year Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year Ultimate Health Care Cost Trend Rate Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Year that Rate Reaches Ultimate Trend Rate Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate Effect of One Percentage Point Increase on Service and Interest Cost Components Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation Effect of One Percentage Point Decrease on Service and Interest Cost Components Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation Projected Benefit Obligation Funded Status Thresholds Fixed Income Projected Benefit Obligation Funded Status Thresholds Fixed Income Projected Benefit Obligation Funded Status Thresholds Fixed Income Projected Benefit Obligation Funded Status Thresholds Equity Projected Benefit Obligation Funded Status Thresholds Equity Projected Benefit Obligation Funded Status Thresholds Equity Projected Benefit Obligation Funded Status Thresholds Projected Benefit Obligation Funded Status Thresholds Projected Benefit Obligation Funded Status Thresholds Target Plan Asset Allocations Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Expected Future Benefit Payments, Next Twelve Months Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months Expected Future Benefit Payments, Year Two Defined Benefit Plan, Expected Future Benefit Payment, Year Two Expected Future Benefit Payments, Year Three Defined Benefit Plan, Expected Future Benefit Payment, Year Three Expected Future Benefit Payments, Year Four Defined Benefit Plan, Expected Future Benefit Payment, Year Four Expected Future Benefit Payments, Year Five Defined Benefit Plan, Expected Future Benefit Payment, Year Five Expected Future Benefit Payments, Five Fiscal Years Thereafter Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter Defined Contribution Plan, Cost Defined Contribution Plan, Cost Net Effect of Settlement on Other Comprehensive Income and Regulatory Assets Net Effect of Settlement on Other Comprehensive Income and Regulatory Assets Net Effect of Settlement on Other Comprehensive Income and Regulatory Assets Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant Medicare Subsidies Received Medicare Subsidies Received Medicare Subsidies Received Defined Benefit Plan, Benefit Obligation, Benefits Paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Reconciliation of Basis Difference [Table Text Block] Reconciliation of Basis Difference [Table Text Block] [Table Text Block] for Reconciliation of Basis Difference [Table] Schedule of Related Party Transactions [Table Text Block] Schedule of Related Party Transactions [Table Text Block] Summarized Balance Sheet Financial Information, Equity Method Investment [Table Text Block] Summarized Balance Sheet Financial Information, Equity Method Investment [Table Text Block] Summarized Balance Sheet Financial Information, Equity Method Investment [Table Text Block] Summarized Income Statement Financial Information, Equity Method Investment [Table Text Block] Summarized Income Statement Financial Information, Equity Method Investment [Table Text Block] Summarized Income Statement Financial Information, Equity Method Investment [Table Text Block] Reconciliation of Equity in Earnings of Unconsolidated Affiliates [Table Text Block] Reconciliation of Equity in Earnings of Unconsolidated Affiliates [Table Text Block] [Table Text Block] for Reconciliation of Equity in Earnings of Unconsolidated Affiliates [Table] Common Equity Dividend Restrictions [Abstract] Common Equity Dividend Restrictions [Abstract] Preferred Stock, Shares Outstanding Preferred Stock, Shares Outstanding Retained Earnings, Restricted Retained Earnings, Restricted The amount of retained earnings which are restricted from being paid out in dividends. Paying out this amount would cause the Company to exceed it's debt to total capitalization ratio established by the Company's debt covenants. Retained Earnings, Unrestricted Retained Earnings, Unrestricted The amount of retained earnings which are available to be paid out in dividends. Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Redeemable during the next 12 months Garfield Industrial Authority, January 1, 2025 [Member] Muskogee Industrial Authority, Janaury 1, 2025 [Member] Muskogee Industrial Authority, June 1, 2027 [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Long term debt, gross Total long-term debt Percent of Principal Amount Subject to Optional Tender Percent of Principal Amount Subject to Optional Tender Percent of Principal Amount Subject to Optional Tender Date Due Debt Instrument, Maturity Date Debt Instrument, Repurchased Face Amount Debt Instrument, Repurchased Face Amount Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed Redemption Premium Redemption Premium Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months Long-term Debt, Maturities, Repayments of Principal in Year Two Long-term Debt, Maturities, Repayments of Principal in Year Two Long-term Debt, Maturities, Repayments of Principal in Year Three Long-term Debt, Maturities, Repayments of Principal in Year Three Long-term Debt, Maturities, Repayments of Principal in Year Four Long-term Debt, Maturities, Repayments of Principal in Year Four Long-term Debt, Maturities, Repayments of Principal in Year Five Long-term Debt, Maturities, Repayments of Principal in Year Five Accrued Environmental Loss Contingencies, Noncurrent Accrued Environmental Loss Contingencies, Noncurrent Schedule of Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block] Schedule of Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block] Schedule of Defined Benefit Plans Disclosures [Table Text Block] Schedule of Defined Benefit Plans Disclosures [Table Text Block] Schedule of Capitalized Pension and Postretirement Cost [Table Text Block] Schedule of Capitalized Pension and Postretirement Cost [Table Text Block] Schedule of Capitalized Pension and Postretirement Cost [Table Text Block] Schedule of Assumptions Used [Table Text Block] Schedule of Assumptions Used [Table Text Block] Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block] Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block] Projected Benefit Obligation Funded Status Thresholds [Table Text Block] Projected Benefit Obligation Funded Status Thresholds [Table Text Block] Projected Benefit Obligation Funded Status Thresholds [Table Text Block] Pension Plan Equity Asset Allocation Table [Table Text Block] Pension Plan Equity Asset Allocation Table [Table Text Block] Pension Plan Equity Allocation Table [Table Text Block] Schedule of Allocation of Plan Assets [Table Text Block] Schedule of Allocation of Plan Assets [Table Text Block] Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets [Table Text Block] Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets [Table Text Block] Schedule of Expected Benefit Payments [Table Text Block] Schedule of Expected Benefit Payments [Table Text Block] Supplemental Cash Flow Information [Table] Supplemental Cash Flow Information [Table] Supplemental Cash Flow Information [Table] Supplemental Cash Flows [Axis] Supplemental Cash Flows [Axis] Supplemental Cash Flows [Axis] Supplemental Cash Flows [Domain] Supplemental Cash Flows [Domain] Supplemental Cash Flows [Domain] NON-CASH INVESTING AND FINANCING ACTIVITIES Noncash Investing and Financing Items [Abstract] Installment payments for Tinker electric distribution system Installment payments for Tinker electric distribution system Installment payments for Tinker electric distribution system Power plant long-term service agreement Power Plant Long-Term Service Agreement Power Plant Long-Term Service Agreement Investment in Enable Investment in Enable Investment in Enable SUPPLEMENTAL CASH FLOW INFORMATION Supplemental Cash Flow Elements [Abstract] Interest (net of interest capitalized) Interest Paid, Net Income taxes (net of income tax refunds) Income Taxes Paid, Net Interest costs capitalized Interest Costs Capitalized Related Party Transactions [Abstract] Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Scenario [Axis] Excluding Fuel Purchases [Member] Excluding Fuel Purchases [Member] Excluding Fuel Purchases [Member] Employment Costs [Member] Employment Costs [Member] Employment Costs [Member] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Related Party Transaction [Axis] Related Party Transaction [Axis] Related Party Transaction [Domain] Related Party Transaction [Domain] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party Expected Settlement Charge Expected Settlement Charge Expected Settlement Charge Revenue from Related Parties Revenue from Related Parties Related Party Transaction, Purchases from Related Party Related Party Transaction, Purchases from Related Party Income Statement [Abstract] OPERATING REVENUES Revenues [Abstract] Electric Utility Electric Domestic Regulated Revenue Natural Gas Midstream Operations (Note 1) Gas Gathering, Transportation, Marketing and Processing Revenue Total operating revenues Revenues COST OF SALES Cost of Goods Sold [Abstract] Electric Utility Cost of Domestic Regulated Electric Natural Gas Midstream Operations (Note 1) Gas Gathering, Transportation, Marketing and Processing Costs Total cost of sales Cost of Goods and Services Sold OPERATING EXPENSES Operating Expenses [Abstract] Other operation and maintenance Other Cost and Expense, Operating Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Gain on insurance proceeds Gain on Business Interruption Insurance Recovery Taxes other than income Taxes, Miscellaneous Total operating expenses Operating Expenses Operating income (loss) Operating Income (Loss) OTHER INCOME (EXPENSE) Nonoperating Income (Expense) [Abstract] Allowance for equity funds used during construction Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity Other income Other Nonoperating Income Other expense Other Nonoperating Expense Net other income Nonoperating Income (Expense) INTEREST EXPENSE Interest Expense [Abstract] Interest on long-term debt Interest Expense, Long-term Debt Allowance for borrowed funds used during construction Public Utilities, Allowance for Funds Used During Construction, Additions Interest on short-term debt and other interest charges Interest Expense, Short-term Borrowings Interest expense Interest Expense INCOME BEFORE TAXES Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest INCOME TAX (BENEFIT) EXPENSE NET INCOME Net Income (Loss), Including Portion Attributable to Noncontrolling Interest BASIC AVERAGE COMMON SHARES OUTSTANDING Weighted Average Number of Shares Outstanding, Basic DILUTED AVERAGE COMMON SHARES OUTSTANDING Weighted Average Number of Shares Outstanding, Diluted BASIC EARNINGS PER AVERAGE COMMON SHARE Earnings Per Share, Basic DILUTED EARNINGS PER AVERAGE COMMON SHARE Earnings Per Share, Diluted DIVIDENDS DECLARED PER COMMON SHARE Common Stock, Dividends, Per Share, Declared Cash Flow, Supplemental Disclosures [Text Block] Cash Flow, Supplemental Disclosures [Text Block] Common Equity Common Equity [Text Block] Disclosures related to earnings per share and current quarter activities in the automatic dividend reinvestment and stock purchase plan. Summarized Financial Information of Equity Method Investment [Table] Summarized Financial Information of Equity Method Investment [Table] Summarized Financial Information of Equity Method Investment [Table] Summarized Financial Information of Equity Method Investment [Axis] Summarized Financial Information of Equity Method Investment [Axis] Summarized Financial Information of Equity Method Investment [Axis] Summarized Financial Information of Equity Method Investment [Domain] Summarized Financial Information of Equity Method Investment [Domain] [Domain] for Summarized Financial Information of Equity Method Investment [Axis] Summarized Financial Information of Equity Method Investment [Line Items] Summarized Financial Information of Equity Method Investment [Line Items] [Line Items] for Summarized Financial Information of Equity Method Investment [Table] Current assets Equity Method Investment, Summarized Financial Information, Current Assets Non-current assets Equity Method Investment, Summarized Financial Information, Noncurrent Assets Current liabilities Equity Method Investment, Summarized Financial Information, Current Liabilities Non-current liabilities Equity Method Investment, Summarized Financial Information, Noncurrent Liabilities Statement of Comprehensive Income [Abstract] Pension Plan and Restoration of Retirement Income Plan: Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax [Abstract] Amortization of deferred net loss, net of tax of $1.4, $1.7 and $2.2, respectively Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax Net gain (loss) arising during the period, net of tax of $0.2, ($0.6) and ($5.8), respectively Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax Amortization of prior service cost, net of tax of $0.0, $0.0 and $0.0, respectively Other Comprehensive Income Amortization Of Defined Benefit Pension Plans Net Prior Service Cost Recognized in Net Periodic Pension Cost, Tax Other Comprehensive Income Amortization Of Defined Benefit Pension Plans Net Prior Service Cost Recognized in Net Periodic Pension Cost, Tax Settlement cost, net of tax of $1.4, $3.2 and $2.9, respectively Other Comprehensive Income (Loss), Defined Benefit Plan, Adjustment for Settlement or Curtailment Gain (Loss), Tax Postretirement plans: Defined Benefit Postretirement Plans [Abstract] -- None. No documentation exists for this element. -- Settlement cost, net of tax of $0.2, $0.0 and $0.0, respectively Other Comprehensive Income Loss Prior Service Credit Arising During The Period Recognized In Net Periodic Benefit Cost Tax Effect Other Comprehensive Income Loss Prior Service Credit Arising During The Period Recognized In Net Periodic Benefit Cost Tax Effect Prior service cost arising during the period, net of tax of $4.0, $0.0 and $0.0, respectively Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, Tax Amortization of deferred net loss, net of tax of $0.0, $0.0 and $0.8, respectively Other Comprehensive Income Reclassification Of Defined Benefit Postretirement Plans Net Gain Loss Recognized In Net Periodic Benefit Cost Tax Other Comprehensive Income Reclassification Of Defined Benefit Postretirement Plans Net Gain Loss Recognized In Net Periodic Benefit Cost Tax Net (loss) gain arising during the period, net of tax of ($0.2), $0.1 and $5.6, respectively Other Comprehensive Income Postretirement Plans Net Unamortized Gain Loss Arising During the Period, Tax Other Comprehensive Income Postretirement Plans Net Unamortized Gain Loss Arising During the Period, Tax Amortization of deferred net transition obligation Other Comprehensive Income (Loss), Defined Benefit Plan, Transition Asset (Obligation), Reclassification Adjustment from AOCI, Tax Amortization of prior service cost, net of tax of ($0.3), ($1.0) and ($1.1), respectively Other Comprehensive Income (Loss) Amortization Defined Benefit Postretirement Plans Net Prior Service Cost Recognized In Net Periodic Benefit Cost Tax Effect Tax effect on adjustment out of other comprehensive income for prior service costs recognized as a component of net periodic postretirement benefit cost during the period. Amortization of deferred interest rate swap hedging losses, net of tax of $0, $0 and $0.0, respectively Other Comprehensive Income Reclassification Adjustment On Interest Rate Swaps Included In Net Income Tax Other Comprehensive Income Reclassification Adjustment On Interest Rate Swaps Included In Net Income, Tax Deferred commodity contracts hedging (gains) losses reclassified in net income Deferred commodity contracts hedging gains (losses) Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax Accounting Pronouncement [Abstract] Accounting Pronouncement [Abstract] New Accounting Pronouncements and Changes in Accounting Principles [Text Block] New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Accounting Records [Abstract] Accounting Records [Abstract] Other Postretirement Benefit Plans, Defined Benefit [Member] Benefit Obligations [Member] Regulatory Asset [Member] Regulatory Asset [Member] Regulatory Asset [Member] Components of Benefit Obligation Regulatory Asset [Axis] Components of Benefit Obligation Regulatory Asset [Axis] Components of Benefit Obligation Regulatory Asset [Axis] Components of Benefit Obligation Regulatory Asset [Domain] Components of Benefit Obligation Regulatory Asset [Domain] Components of Benefit Obligation Regulatory Asset [Domain] Defined Benefit Plans Income Loss [Member] Defined Benefit Plans Income Loss [Member] Defined Benefit Plans Income Loss [Member] Prior Service Cost [Member] Prior Service Cost [Member] Prior Service Cost [Member] Components of Benefit Obligation Regulatory Asset Components of Benefit Obligation Regulatory Asset Components of Benefit Obligation Regulatory Asset Smart Grid Costs to be Recovered Smart Grid Costs to be Recovered Smart grid costs to be recovered through a rider Deferred Storm and Property Reserve Deficiency, Current Deferred Storm and Property Reserve Deficiency, Current Statement of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES Net Cash Provided by (Used in) Operating Activities [Abstract] Net income Adjustments to reconcile net income to net cash provided from operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Amortization and Accretion, Net Deferred income taxes and investment tax credits, net Deferred Income Taxes and Tax Credits Equity in earnings of unconsolidated affiliates Distributions from unconsolidated affiliates increase decrease in distributions from unconsolidated affiliates increase decrease in distributions from unconsolidated affiliates Allowance for equity funds used during construction Gain on disposition of assets Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property Stock-based compensation Share-based Compensation Regulatory assets Increase Decrease In Regulatory Assets Noncurrent The net change during the reporting period in the value of noncurrent assets that are created when regulatory agencies permit public utilities to defer expenses to the balance sheet. Regulatory liabilities Increase Decrease In Regulatory Liabilities Noncurrent Increase Decrease In Regulatory Liabilities Noncurrent Other assets Increase (Decrease) in Other Noncurrent Assets Other liabilities Increase (Decrease) in Other Noncurrent Liabilities Change in certain current assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable and accrued unbilled revenues, net Increase (Decrease) in Accounts Receivable Accounts receivable - unconsolidated affiliates Increase (Decrease) in Accounts Receivable, Related Parties Accrued unbilled revenues Increase (Decrease) in Unbilled Receivables Income taxes receivable Increase (Decrease) in Income Taxes Receivable Fuel, materials and supplies inventories Increase (Decrease) in Inventories Fuel recoveries Increase (Decrease) in Deferred Fuel Costs Other current assets Increase (Decrease) in Other Current Assets Accounts payable Increase (Decrease) in Accounts Payable Fuel clause over recoveries Increase (Decrease) In Deferred Fuel Costs Current Liabilities Increase (Decrease) In Deferred Fuel Costs Current Liabilities Other current liabilities Increase (Decrease) in Other Current Liabilities Net cash provided from operating activities Net Cash Provided by (Used in) Operating Activities CASH FLOWS FROM INVESTING ACTIVITIES Net Cash Provided by (Used in) Investing Activities [Abstract] Capital expenditures (less allowance for equity funds used during construction) Payments to Acquire Productive Assets Return of capital - equity method investments Proceeds from Equity Method Investment, Distribution, Return of Capital Proceeds from sale of assets Proceeds from Sale of Productive Assets Investment in unconsolidated affiliates Investments in and Advances to Affiliates, at Fair Value, Period Increase (Decrease) Acquisition of gathering assets Payments to Acquire Businesses, Net of Cash Acquired Proceeds from insurance Proceeds from Insurance Settlement, Investing Activities Reimbursement of capital expenditures Proceeds from Contribution in Aid of Construction Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities CASH FLOWS FROM FINANCING ACTIVITIES Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from long-term debt Proceeds from Issuance of Long-term Debt Issuance (expense) of common stock Proceeds from Issuance of Common Stock Dividends paid on common stock Payments of Ordinary Dividends, Common Stock Other Proceeds from (Payments for) Other Financing Activities Payment of long-term debt Repayments of Long-term Debt (Decrease) increase in short-term debt Proceeds from (Repayments of) Short-term Debt Changes in advances with unconsolidated affiliates Increase (Decrease) in Due to Affiliates Contributions from noncontrolling interest partners Proceeds from Noncontrolling Interests Repayment of line of credit Repayments of Long-term Lines of Credit Increase in long-term revolver Payments for Repurchase of Common Stock Distributions to noncontrolling interest partners Payments of Ordinary Dividends, Noncontrolling Interest Net cash provided from (used in) financing activities Net Cash Provided by (Used in) Financing Activities NET CHANGE IN CASH AND CASH EQUIVALENTS Cash and Cash Equivalents, Period Increase (Decrease) CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD Cash and Cash Equivalents, at Carrying Value CASH AND CASH EQUIVALENTS AT END OF PERIOD Schedule II Valuation and Qualifying Accounts [Table Text Block] Schedule II Valuation and Qualifying Accounts [Table Text Block] Schedule II Valuation and Qualifying Accounts [Table Text Block] Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Business Segments [Axis] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Report of Business Segments Segment Reporting Disclosure [Text Block] Schedule of Regulatory Assets and Liabilities [Table Text Block] Schedule of Regulatory Assets and Liabilities [Table Text Block] A table of assets and liabilities that are created when regulatory agencies permit public utilities to defer certain costs and recognition of certain revenues that are included in rate-setting to the balance sheet. Components of Benefit Obligation Regulatory Asset [Table Text Block] Components of Benefit Obligation Regulatory Asset [Table Text Block] Components of Benefit Obligation Regulatory Asset [Table Text Block] Schedule of Net Periodic Benefit Cost Not yet Recognized [Table Text Block] Schedule of Net Periodic Benefit Cost Not yet Recognized [Table Text Block] Schedule of Jointly Owned Utility Plants [Table Text Block] Schedule of Jointly Owned Utility Plants [Table Text Block] Schedule of Unamortized Computer Software Costs [Table Text Block] Schedule of Unamortized Computer Software Costs [Table Text Block] [Table Text Block] for Schedule of Unamortized Computer Software Costs [Table] Schedule of Computer Software Costs, Amortization [Table Text Block] Schedule of Computer Software Costs, Amortization [Table Text Block] Schedule of Computer Software Costs, Amortization [Table Text Block] Schedule of Change in Asset Retirement Obligation [Table Text Block] Schedule of Change in Asset Retirement Obligation [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [Table Text Block] Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [Table Text Block] Distribution Type [Axis] Distribution Type [Axis] Distribution Type [Domain] Distribution Type [Domain] Preferred Partner [Member] Preferred Partner [Member] Distribution Made to Limited Partner, Cash Distributions Paid Distribution Made to Limited Partner, Cash Distributions Paid Timing Differences Related to Equity Method Investee Net Income Timing Differences Related to Equity Method Investee Net Income Timing Differences Related to Equity Method Investee Net Income Net Income Used to Calculate Equity in Earnings Net Income Used to Calculate Equity in Earnings Net Income Used to Calculate Equity in Earnings Proportionate Unconsolidated Affiliate Net Income Proportionate Unconsolidated Affiliate Net Income Proportionate Share of Equity Method Investee Net Income, Before Adjustments Goodwill, Impairment Loss OGE Energy's share of Enable net income (loss) Proportionate Share of Unconsolidated Affiliate Net Income Proportionate Share of Unconsolidated Affiliate Net Income Amortization of basis difference Equity in Earnings Amortization of Basis Difference Equity in Earnings Amortization of Basis Difference Equity in earnings of unconsolidated affiliates Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Performance Units Total Shareholder Return Valuation Assumptions [Table Text Block] Performance Units Total Shareholder Return Valuation Assumptions [Table Text Block] Performance Units Total Shareholder Return Valuation Assumptions [Table Text Block] Performance Units Earnings Per Share Valuation Assumptions [Table Text Block] Performance Units Earnings Per Share Valuation Assumptions [Table Text Block] Performance Units Earnings Per Share Valuation Assumptions [Table Text Block] Restricted Stock Valuation Assumptions [Table Text Block] Restricted Stock Valuation Assumptions [Table Text Block] Restricted Stock Valuation Assumptions [Table Text Block] Share-based Compensation, Activity [Table Text Block] Share-based Compensation, Activity [Table Text Block] Schedule of Nonvested Share Activity [Table Text Block] Schedule of Nonvested Share Activity [Table Text Block] Fair Value of Vested Performance Units and Restricted Stock [Table Text Block] Fair Value of Vested Performance Units and Restricted Stock [Table Text Block] Fair Value of Vested Performance Units and Restricted Stock [Table Text Block] Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block] Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block] Exercised Stock Options [Table Text Block] Exercised Stock Options [Table Text Block] Exercised Stock Options [Table Text Block] ASSETS Assets [Abstract] CURRENT ASSETS Assets, Current [Abstract] Cash and cash equivalents Accounts receivable, less reserve of $1.5 and $1.5, respectively Accounts Receivable, Net, Current Accrued unbilled revenues Unbilled Receivables, Current Income taxes receivable Income Taxes Receivable, Current Fuel inventories Inventory, Net Materials and supplies, at average cost Other Inventory, Supplies, Gross Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Current Total current assets Assets, Current OTHER PROPERTY AND INVESTMENTS Other property and investments [Abstract] Other property and investments [Abstract] Investment in unconsolidated affiliates Equity Method Investments Other Other Long-term Investments Total other property and investments Other Investments PROPERTY, PLANT AND EQUIPMENT Property, Plant and Equipment, Net [Abstract] In service Public Utilities, Property, Plant and Equipment, Plant in Service Construction work in progress Construction in Progress, Gross Total property, plant and equipment Less accumulated depreciation DEFERRED CHARGES AND OTHER ASSETS Other Assets, Noncurrent [Abstract] Regulatory assets Other Other Assets, Miscellaneous, Noncurrent Total deferred charges and other assets Other Assets, Noncurrent TOTAL ASSETS Assets LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] CURRENT LIABILITIES Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Dividends payable Dividends Payable, Current Customer deposits Customer Deposits, Current Accrued taxes Taxes Payable, Current Accrued interest Interest Payable, Current Accrued compensation Employee-related Liabilities, Current Long-term debt due within one year Other Other Liabilities, Current Total current liabilities Liabilities, Current LONG-TERM DEBT DEFERRED CREDITS AND OTHER LIABILITIES Liabilities, Other than Long-term Debt, Noncurrent [Abstract] Accrued benefit obligations Liability, Defined Benefit Plan, Noncurrent Deferred income taxes Regulatory liabilities Other Other Liabilities, Noncurrent Total deferred credits and other liabilities Liabilities, Other than Long-term Debt, Noncurrent Total liabilities Liabilities COMMITMENTS AND CONTINGENCIES (NOTE 13) Commitments and Contingencies STOCKHOLDERS' EQUITY Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Common stockholders' equity Common Stocks, Including Additional Paid in Capital Retained earnings TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity Change due to Tax Law [Axis] Change due to Tax Law [Axis] Change due to Tax Law [Axis] Change due to Tax Law [Domain] Change due to Tax Law [Domain] [Domain] for Change due to Tax Law [Axis] Tax Benefit Due to Tax Law Change [Member] Tax Benefit Due to Tax Law Change [Member] Tax Benefit Due to Tax Law Change [Member] Tax Expense Due to Tax Law Change [Member] Tax Expense Due to Tax Law Change [Member] Tax Expense Due to Tax Law Change [Member] Electric Utility [Member] Electric Utility [Member] Electric Utility [Member] Other Operations [Member] Other Segments [Member] Eliminations [Member] Intersegment Eliminations [Member] Operating revenues Cost of sales Equity in earnings of unconsolidated affiliates Other income (expense) Other Nonoperating Income (Expense) Interest expense Income tax expense (benefit) (A) Less: Net income attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest NET INCOME ATTRIBUTABLE TO OGE ENERGY Net Income (Loss) Attributable to Parent Investment in unconsolidated affiliates Total assets Capital expenditures Payments to Acquire Productive Assets Including Payments for Business Combination Payments to Acquire Productive Assets Including Payments for Business Combination Statement of Stockholders' Equity [Abstract] Common Stock Premium on Common Stock Additional Paid-in Capital [Member] Retained Earnings Retained Earnings [Member] Accumulated Other Comprehensive Income (Loss) Treasury Stock Treasury Stock [Member] Common Stock, Shares, Outstanding Common Stock, Shares, Outstanding Net Income (Loss), Including portion attributable to noncontrolling interest, Number of Shares Net Income (Loss), Including portion attributable to noncontrolling interest, Number of Shares Net Income (Loss), Including portion attributable to noncontrolling interest, Number of Shares Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification, Number of Shares Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification, Number of Shares Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification, Number of Shares Other Comprehensive Income (Loss), Net of Tax, Number of Shares Other Comprehensive Income (Loss), Net of Tax, Number of Shares Other Comprehensive Income (Loss), Net of Tax, Number of Shares Other comprehensive income, net of tax Other Comprehensive Income (Loss), Net of Tax Dividends, Common Stock, Cash, Number of Shares Dividends, Common Stock, Cash, Number of Shares Dividends, Common Stock, Cash, Number of Shares Dividends declared on common stock Dividends, Common Stock, Cash Stock Issued During Period, Shares, New Issues Expense of common stock Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition, Number of Shares Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition, Number of Shares Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition, Number of Shares Stock Issued During Period, Value, New Issues, Number of Shares Stock Issued During Period, Value, New Issues, Number of Shares Stock Issued During Period, Value, New Issues, Number of Shares Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Contributions from noncontrolling interest partners Deconsolidation of Enogex Holdings Deconsolidation of subsidiary Deconsolidation of subsidiary Deferred income taxes attributable to contributions from noncontrolling interest partners Deferred Income Taxes Attributable To Contributions From Noncontrolling Interest Partners Deferred income taxes arising from the cash inflow contributed by noncontrolling interests that purchase additional shares or otherwise increase their ownership stake in a subsidiary of the entity. 2-for-1 forward stock split Adjustments to Additional Paid in Capital, Stock Split Balance Depreciation, Depletion and Amortization [Abstract] Transmission Equipment [Member] Transmission Equipment [Member] Transmission Equipment [Member] Provision for Depreciation Rate Provision for Depreciation Rate Provision for Depreciation Rate Projected provision for depreciation in next fiscal year Projected provision for depreciation in next fiscal year Projected provision for depreciation in next fiscal year Percent Of Intangible Plant Balance Amortizable Percent Of Intangible Plant Balance Amortizable Percent Of Intangible Plant Balance Amortizable Percent of Intangible Plant Balance Amortizable Thereafter Percent of Intangible Plant Balance Amortizable Thereafter Percent of Intangible Plant Balance Amortizable Thereafter Document and Entity Information [Abstract] Document and Entity Information [Abstract]. Document Information [Table] Document Information [Table] Document Information, Document [Axis] Document Information, Document [Axis] Document [Domain] Document [Domain] Document Information [Line Items] Document Information [Line Items] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Public Float Entity Public Float Equity Components [Axis] Equity Component [Domain] Retained Earnings [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Net income attributable to OGE Energy Basic Average Common Shares Outstanding Contingently Issuable Shares (Performance and Restricted Stock Units) Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares Diluted Average Common Shares Outstanding Earnings Per Share, Basic and Diluted [Abstract] Earnings Per Share, Basic and Diluted [Abstract] Basic earnings per average common share attributable to OGE Energy common shareholders Diluted earnings per average common share attributable to OGE Energy common shareholders Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Segment Reporting Information, by Segment [Table Text Block] Quarterly Financial Information [Text Block] Quarterly Financial Information [Text Block] Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Pension Plan and Restoration of Retirement Income Plan: Amortization of deferred net loss, net of tax of $1.4, $1.7 and $2.2, respectively Amortization of prior service cost, net of tax of $0.0, $0.0 and $0.0, respectively Other Comprehensive Income Amortization of Defined Benefit Pension Plan and Restoration Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax Other Comprehensive Income Amortization of Defined Benefit Pension Plan and Restoration Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax Net gain (loss) arising during the period, net of tax of $0.2, ($0.6) and ($5.8), respectively Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax Settlement cost, net of tax of $1.4, $3.2 and $2.9, respectively Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), after Tax Postretirement Benefit Plans: Amortization of prior service cost, net of tax of ($0.3), ($1.0) and ($1.1), respectively Other Comprehensive Income Amortization Of Defined Benefit Postretirement Plans Net Prior Service Cost Recognized In Net Periodic Postretirement Cost Net Of Tax Other Comprehensive Income Amortization Of Defined Benefit Postretirement Plans Net Prior Service Cost Recognized In Net Periodic Postretirement Cost Net Of Tax Amortization of deferred net loss, net of tax of $0.0, $0.0 and $0.8, respectively Other Comprehensive Income Reclassification Of Defined Benefit Postretirement Plans Net Gain Loss Recognized In Net Periodic Benefit Cost Net Of Tax Other Comprehensive Income Reclassification Of Defined Benefit Postretirement Plans Net Gain Loss Recognized In Net Periodic Benefit Cost Net Of Tax Prior service cost arising during the period, net of tax of $4.0, $0.0 and $0.0, respectively Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, after Tax Net (loss) gain arising during the period, net of tax of ($0.2), $0.1 and $5.6, respectively Other Comprehensive Income Postretirement Plans Net Unamortized Gain Loss Arising During Period, Net of Tax Other Comprehensive Income Postretirement Plans Net Unamortized Gain Loss Arising During Period, Net of Tax Amortization of deferred net transition obligation, net of tax of $_, $0 and $0, respectively Other Comprehensive Income (Loss), Defined Benefit Plan, Transition Asset (Obligation), Reclassification Adjustment from AOCI, after Tax Settlement cost, net of tax of $0.2, $0.0 and $0.0, respectively Other Comprehensive Income Prior Service Credit Arising During The Period Recognized In Net Periodic Postretirement Cost Net of Tax Other Comprehensive Income Prior Service Credit Arising During The Period Recognized In Net Periodic Postretirement Cost Net of Tax Deferred commodity contracts hedging losses reclassified in net income, net of tax of $0, $0 and $0, respectively Deferred commodity contracts hedging gains (losses), net of tax of $0, $0 and $0, respectively Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Amortization of deferred interest rate swap hedging losses, net of tax of $0, $0 and $0.0, respectively Other Comprehensive Income Amortization of Interest Rate Swap Net Of Tax Other Comprehensive Income Amortization of Interest Rate Swap Net Of Tax Other comprehensive income, net of tax Comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Less: Comprehensive income attributable to noncontrolling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Less: Deconsolidation of Enogex Holdings Noncontrolling Interest, Decrease from Deconsolidation Total comprehensive income attributable to OGE Energy Comprehensive Income (Loss), Net of Tax, Attributable to Parent Schedule of Long-term Debt Instruments [Table Text Block] Schedule of Long-term Debt Instruments [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Fair Value, by Balance Sheet Grouping [Table Text Block] Fair Value, by Balance Sheet Grouping [Table Text Block] Loss Contingencies [Table] Loss Contingencies [Table] Environmental Compliance [Axis] Environmental Compliance [Axis] Environmental Compliance [Axis] Environmental Compliance [Domain] Environmental Compliance [Domain] [Domain] for Environmental Compliance [Axis] New Source Review [Member] New Source Review [Member] New Source Review [Member] Clean Power Plan [Member] Clean Power Plan [Member] Clean Power Plan [Member] New Long-Term Service Agreement [Axis] New Long-Term Service Agreement [Axis] New Long-Term Service Agreement [Axis] New Long-Term Service Agreement [Domain] New Long-Term Service Agreement [Domain] [Domain] for New Long-Term Service Agreement [Axis] OG&E long-term service agreement commitments [Member] OG&E long-term service agreement commitments [Member] OG&E long-term service agreement commitments [Member] OG&E cogeneration capacity and fixed operation and maintenance payments [Member] OG&E cogeneration capacity and fixed operation and maintenance payments [Member] OG&E cogeneration capacity and fixed operation and maintenance payments [Member] OG&E expected cogeneration energy payments [Member] OG&E expected cogeneration energy payments [Member] OG&E expected cogeneration energy payments [Member] OG&E minimum fuel purchase commitments [Member] OG&E minimum fuel purchase commitments [Member] OG&E minimum fuel purchase commitments [Member] OG&E expected wind purchase commitments [Member] OG&E expected wind purchase commitments [Member] OG&E expected wind purchase commitments [Member] Mustang Modernization [Member] Mustang Modernization [Member] Mustang Modernization [Member] Environmental compliance plan expenditures [Member] Environmental Compliance Plan [Member] Environmental Compliance Plan [Member] Public Utility Regulatory Policy Act of 1978 [Member] Public Utility Regulatory Policy Act of 1978 [Member] Public Utility Regulatory Policy Act of 1978 [Member] OG&E total cogeneration payments [Member] OG&E total cogeneration payments [Member] OG&E total cogeneration payments [Member] OG&E capacity payments [Member] OG&E capacity payments [Member] OG&E capacity payments [Member] CPV Keenan [Member] CPV Keenan [Member] CPV Keenan [Member] Edison Mission Energy [Member] Edison Mission Energy [Member] Edison Mission Energy [Member] FPL Energy [Member] FPL Energy [Member] FPL Energy [Member] NextEra Energy [Member] NextEra Energy [Member] NextEra Energy [Member] Operating Lease Obligations [Axis] Operating Lease Obligations [Axis] Operating Lease Obligations [Axis] Operating Lease Obligations [Domain] Operating Lease Obligations [Domain] Operating Lease Obligations [Domain] OG&E Railcar Lease Agreement [Member] OG&E Railcar Lease Agreement [Member] OG&E Railcar Lease Agreement [Member] OG&E Wind Farm Land Lease Agreements [Member] OG&E Wind Farm Land Lease Agreements [Member] OG&E Wind Farm Land Lease Agreements OGE Energy Building Lease [Member] OGE Energy Building Lease [Member] Building Lease [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Operating Leases, Future Minimum Payments Due, Next Twelve Months Operating Leases, Future Minimum Payments Due, Next Twelve Months Operating Leases, Future Minimum Payments, Due in Two Years Operating Leases, Future Minimum Payments, Due in Two Years Operating Leases, Future Minimum Payments, Due in Three Years Operating Leases, Future Minimum Payments, Due in Three Years Operating Leases, Future Minimum Payments, Due in Four Years Operating Leases, Future Minimum Payments, Due in Four Years Operating Leases, Future Minimum Payments, Due in Five Years Operating Leases, Future Minimum Payments, Due in Five Years Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Due Operating Leases, Rent Expense, Net Operating Leases, Rent Expense, Net Loss Contingency, Range of Possible Loss, Maximum Loss Contingency, Estimate of Possible Loss Purchase Obligation, Due in Next Twelve Months Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months Unrecorded Unconditional Purchase Obligation, Due within Two Years Unrecorded Unconditional Purchase Obligation, Due within Two Years Unrecorded Unconditional Purchase Obligation, Due within Three Years Unrecorded Unconditional Purchase Obligation, Due within Three Years Unrecorded Unconditional Purchase Obligation, Due within Four Years Unrecorded Unconditional Purchase Obligation, Due within Four Years Unrecorded Unconditional Purchase Obligation, Due within Five Years Unrecorded Unconditional Purchase Obligation, Due within Five Years Long-term Purchase Commitment, Amount Unrecorded Unconditional Purchase Obligation Percentage of output purchased Percentage of output purchased Percentage of output purchased Long-term Purchase Commitment, Amount Long-term Purchase Commitment, Amount Utilities Operating Expense, Purchased Power under Long-term Contracts Utilities Operating Expense, Purchased Power under Long-term Contracts Factored-Fired Hours Factored-Fired Hours Factored-Fired Hours Factored-Fired Starts Factored-Fired Starts Factored-Fired Starts Additional Factored-Fired Hours Additional Factored-Fired Hours Additional Factored-Fired Hours Estimated Environmental Capital Costs Estimated Environmental Capital Costs Estimated Environmental Capital Costs Proposed Rate-Based Carbon Reduction Proposed Rate-Based Carbon Reduction Proposed Rate-Based Carbon Reduction Final Rate-Based Carbon Reduction Final Rate-Based Carbon Reduction Final Rate-Based Carbon Reduction Mass-Based Carbon Reduction Mass-Based Carbon Reduction Mass-Based Carbon Reduction Contract Amount Contract Amount Contracted amount to be paid for goods and/or services. Asset Retirement Obligation [Abstract] Asset Retirement Obligations [Table] Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Balance at January 1 Asset Retirement Obligation Accretion expense Asset Retirement Obligation, Accretion Expense Revisions in estimated cash flows Asset Retirement Obligation, Revision of Estimate Additions Asset Retirement Obligation, Liabilities Incurred Liabilities settled Asset Retirement Obligation, Liabilities Settled Balance at December 31 Parenthetical [Abstract] Parenthetical [Abstract] Common Stock, Par or Stated Value Per Share Common Stock, Par or Stated Value Per Share Common Stock, Shares Authorized Common Stock, Shares Authorized Treasury Stock, Shares Treasury Stock, Shares Debt Instrument, Maturity Date Operating income Schedule of Line of Credit Facilities [Table Text Block] Schedule of Line of Credit Facilities [Table Text Block] Income Tax Disclosure [Text Block] Income Tax Disclosure [Text Block] Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring [Member] Fair Value, Measurements, Recurring [Member] OG&E Senior Notes [Member] Og and E Senior Notes [Member] Og and E Senior Notes [Member] OG&E Industrial Authority Bonds [Member] Og And E Industrial Authority Bonds [Member] Og And E Industrial Authority Bonds [Member] OG&E Tinker Debt [Member] OG and E Tinker Debt [Member] OG and E Tinker Debt [Member] OGE Energy Senior Notes [Member] Oge Energy Senior Notes [Member] Oge Energy Senior Notes [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Derivative Assets (Liabilities), at Fair Value, Net Derivative Assets (Liabilities), at Fair Value, Net Total long-term debt Long-Term Debt, Fair Value Long-term Debt, Fair Value Retirement Benefits [Abstract] Equity Funds [Member] Pension Plan [Member] Fair Value Hierarchy [Domain] Defined Benefit Plan, Asset Categories [Axis] Defined Benefit Plan, Asset Categories [Axis] Plan Asset Categories [Domain] Plan Asset Categories [Domain] Group Retiree Medical Insurance Contract [Member] Group Retiree Medical Insurance Contract [Member] Group Retiree Medical Insurance Contract [Member] U.S. Equity Mutual Funds Investment [Member] U.S. Equity Mutual Funds Investment [Member] U.S. Equity Mutual Funds Investment [Member] Cash [Member] Cash [Member] Amortization of net loss Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Level 3 Asset Value, Beginning of Period Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Interest income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Interest Income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Interest Income Dividend income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Dividends Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Dividends Unrealized gains Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Unrealized Gains Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Unrealized Gains Realized losses Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Realized Gains (Losses) Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Realized Gains (Losses) Administrative expenses and charges Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Administrative Expenses and Charges Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Administrative Expenses and Charges Claims paid Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Claims Paid Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Claims Paid Level 3 Asset Value, End of Period Postretirement Plan, Expected Future Benefit Payments, Next Twelve Months Postretirement Plan, Expected Future Benefit Payments in Year One Postretirement Plan, Expected Future Benefit Payments in Year One Postretirement Plan, Expected Future Benefit Payments, Year Two Postretirement Plan, Expected Future Benefit Payments in Year Two Postretirement Plan, Expected Future Benefit Payments in Year Two Postretirement Plan, Expected Future Benefit Payments, Year Three Postretirement Plan, Expected Future Benefit Payments in Year Three Postretirement Plan, Expected Future Benefit Payments in Year Three Postretirement Plan, Expected Future Benefit Payments in Year Four Postretirement Plan, Expected Future Benefit Payments in Year Four Postretirement Plan, Expected Future Benefit Payments in Year Four Postretirement Plan, Expected Future Benefit Payments, Year Five Postretirement Plan, Expected Future Benefit Payments in Year Five Postretirement Plan, Expected Future Benefit Payments in Year Five Postretirement Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter Postretirement Plan, Expected Future Benefit Payments Thereafter Postretirement Plan, Expected Future Benefit Payments Thereafter Postemployment Benefits Liability Postemployment Benefits Liability Jurisdiction [Axis] Jurisdiction [Axis] Jurisdiction [Domain] Jurisdiction [Domain] Jurisdiction [Domain] FERC [Member] FERC [Member] FERC [Member] Regulatory File Date [Axis] Regulatory File Date [Axis] Regulatory File Date [Axis] Regulatory File Date [Domain] Regulatory File Date [Domain] [Domain] for Regulatory File Date [Axis] January 16, 2018 [Member] January 16, 2018 [Member] January 16, 2018 [Member] Recommendation 1 [Member] Recommendation 1 [Member] Recommendation 1 [Member] Recommendation 2 [Member] Recommendation 2 [Member] Recommendation 2 [Member] Change in Allowed Amount [Axis] Change in Allowed Amount [Axis] Change in Allowed Amount [Axis] Change in Allowed Amount [Domain] Change in Allowed Amount [Domain] [Domain] for Change in Allowed Amount [Axis] Change in Allowed Amount [Member] Change in Allowed Amount [Member] Change in Allowed Amount [Member] Dry Scrubber Project [Member] Dry Scrubber Project [Member] Dry Scrubber Project [Member] Environmental Compliance Plan [Member] Commission Recommendation [Axis] Commission Recommendation [Axis] Commission Recommendation [Axis] Commission Recommendation [Domain] Commission Recommendation [Domain] [Domain] for Commission Recommendation [Axis] Oklahoma Public Utility Division Staff [Member] Oklahoma Public Utility Division Staff [Member] Oklahoma Public Utility Division Staff [Member] Public Utilities, Regulatory Proceeding [Axis] Public Utilities, Regulatory Proceeding [Axis] Public Utilities, Regulatory Proceeding [Domain] Public Utilities, Regulatory Proceeding [Domain] SmartHours Program [Member] SmartHours Program [Member] SmartHours [Member] Section 206 Complaint [Member] Section 206 Complaint [Member] Section 206 Complaint [Member] Regional Haze [Member] Regional Haze [Member] Regional Haze [Member] Administrative Law Judge [Member] Administrative Law Judge [Member] Administrative Law Judge [Member] Oklahoma Corporation Commission [Member] Oklahoma Corporation Commission [Member] Oklahoma Corporation Commission [Member] Arkansas Public Service Commission [Member] Arkansas Public Service Commission [Member] Arkansas Public Service Commission [Member] Federal Energy Regulatory Commission [Member] Federal Energy Regulatory Commission [Member] Federal Energy Regulatory Commission [Member] Oklahoma Attorney General [Member] Oklahoma Attorney General [Member] Oklahoma Attorney General [Member] Oklahoma Industrial Electric Consumers [Member] Oklahoma Industrial Electric Consumers [Member] Oklahoma Industrial Electric Consumers [Member] OG&E's Jurisdictional Revenues OG&E's Jurisdictional Revenues OG&E's Jurisdictional Revenues Lost Revenue Associated with Customer Programs - recovered annually Lost Revenue Associated with Customer Programs - recovered annually Lost Revenue Associated with Customer Programs - recovered annually Lost Revenue Associated with Customer Programs Lost Revenue Associated with Customer Programs Lost Revenue Associated with Customer Programs Amount Recorded for Lost Revenue Associated with Customer Programs Amount Recorded for Lost Revenue Associated with Customer Programs Amount Recorded for Lost Revenue Associated with Customer Programs Reduction of Revenue Reduction of Revenue Reduction of Revenue Public Utilities, Property, Plant and Equipment, Construction Work in Progress Public Utilities, Property, Plant and Equipment, Construction Work in Progress Public Utilities, Requested Equity Capital Structure, Percentage Public Utilities, Requested Equity Capital Structure, Percentage Additional Requested Plant Dismantlement Cost Additional Requested Plant Dismantlement Cost Additional Requested Plant Dismantlement Cost Change in Requested Return on Equity Change in Requested Return on Equity Change in Requested Return on Equity Change in Requested Rate Increase Change in Requested Rate Increase Change in Requested Rate Increase Public Utilities, Requested Rate Increase (Decrease), Amount Public Utilities, Requested Rate Increase (Decrease), Amount Public Utilities, Requested Return on Equity, Percentage Public Utilities, Requested Return on Equity, Percentage Investments Since Last Rate Case Investments Since Last Rate Case Investments Since Last Rate Case Recommended Return on Equity Recommended Return on Equity Recommended Return on Equity Recommended Increase (Decrease) in Revenue Recommended Increase (Decrease) in Revenue Recommended Increase (Decrease) in Revenue Reduction to Requested Additional Plant Dismantlement Costs Reduction to Requested Additional Plant Dismantlement Costs Reduction to Requested Additional Plant Dismantlement Costs Recommended Rate Increase (Decrease) Recommended Rate Increase (Decrease) Recommended Rate Increase (Decrease) Recommended Common Equity Percentage Recommended Common Equity Percentage Recommended Common Equity Percentage Public Utilities, Interim Rate Increase (Decrease), Amount Public Utilities, Interim Rate Increase (Decrease), Amount Interim Rate Collected Interim Rate Collected Interim Rate Collected Interim Rate Revenue Reserved Interim Rate Revenue Reserved Interim Rate Revenue Reserved Recommended Capital Structure, Equity Percentage Recommended Capital Structure, Equity Percentage Recommended Capital Structure, Equity Percentage Recommended Capital Structure, Debt Percentage Recommended Capital Structure, Debt Percentage Recommended Capital Structure, Debt Percentage Settlement of Rate Increase Settlement of Rate Increase Settlement of Rate Increase Settlement of Return on Equity, Percentage Settlement of Return on Equity, Percentage Settlement of Return on Equity, Percentage Settlement of Equity Capital Structure, Percentage Settlement of Equity Capital Structure, Percentage Settlement of Equity Capital Structure, Percentage Public Utilities, Approved Rate Increase (Decrease), Amount Public Utilities, Approved Rate Increase (Decrease), Amount Public Utilities, Approved Return on Equity, Percentage Public Utilities, Approved Return on Equity, Percentage Approved Depreciation Reduction from ALJ Recommendation Approved Depreciation Reduction from ALJ Recommendation Approved Depreciation Reduction from ALJ Recommendation ALJ Depreciation Recommendation ALJ Depreciation Recommendation ALJ Depreciation Recommendation Approved Recovery of Short-term Incentive Comp Approved Recovery of Short-term Incentive Comp Approved Recovery of Short-term Incentive Comp Public Utilities, Approved Equity Capital Structure, Percentage Public Utilities, Approved Equity Capital Structure, Percentage Public Utilities, Approved Debt Capital Structure, Percentage Public Utilities, Approved Debt Capital Structure, Percentage Interim Rate Refund Amount Interim Rate Refund Amount Interim Rate Refund Amount Recommended Disallowance for Fuel Adjustment Recommended Disallowance for Fuel Adjustment Recommended Disallowance for Fuel Adjustment Revenue impact of recommended change in return on common equity Revenue impact of recommended change in return on common equity Revenue Impact of Recommended Change in Return on Common Equity Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]