Accounting Policies [Abstract]
Statement [Table]
Statement [Table]
Legal Entity [Axis]
Legal Entity [Axis]
Entity [Domain]
Entity [Domain]
Appalachian Power Co [Member]
Appalachian Power Co [Member]
Appalachian Power Company Member
Indiana Michigan Power Co [Member]
Indiana Michigan Power Co [Member]
Indiana Michigan Power Company Member
Ohio Power Co [Member]
Ohio Power Co [Member]
Ohio Power Company Member
Public Service Co Of Oklahoma [Member]
Public Service Co Of Oklahoma [Member]
Public Service Company Of Oklahoma Member
Southwestern Electric Power Co [Member]
Southwestern Electric Power Co [Member]
Southwestern Electric Power Company Member
Statement [Line Items]
Statement [Line Items]
Organization and Summary of Significant Accounting Policies
Significant Accounting Policies [Text Block]
Fair Value Disclosures [Abstract]
Book Values and Fair Values of Long-term Debt
Fair Value, by Balance Sheet Grouping [Table Text Block]
Other Temporary Investments
Other Temporary Investments [Text Block]
Other Temporary Investments
Debt and Equity Securities Within Other Temporary Investments
Debt and Equity Securities Within Other Temporary Investments [Text Block]
Debt and equity securities within Other Temporary Investments.
Nuclear Trust Fund Investments
Nuclear Trust Fund Investments [Text Block]
Nuclear trust fund investments.
Securities Activity Within the Decommissioning and SNF Trusts
Securities Activity Within Decommissioning and SNF Trusts [Text Block]
Securities Activity Within the decommissioning and SNF trusts.
Investments Classified by Contractual Maturity Date [Table Text Block]
Investments Classified by Contractual Maturity Date [Table Text Block]
Fair Value, Assets and Liabilities Measured on Recurring Basis
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]
Changes in Fair Value of Net Trading Derivatives Classified as Level 3
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
Significant Unobservable Inputs for Level 3
Fair Value Inputs Assets Liabilities Quantitative Information [Table Text Block]
Tabular disclosure of quantitative information about the inputs used in the fair value measurement of assets and liabilities. This disclosure may include, but is not limited to, the fair value of the asset or liability, valuation technique used to measure fair value, the inputs used to measure fair value, the ranges of the inputs, and the weighted averages of the inputs.
Sensitivity of Fair Value Measurements
Fair Value, Option, Qualitative Disclosures Related to Election [Table Text Block]
Statement of Comprehensive Income [Abstract]
Cash Flow Hedges, Tax
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax
Securities Available for Sale, Tax
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax
Amortization of Pension and OPEB Deferred Costs, Tax
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Tax
Pension and OPEB Funded Status, Tax
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Tax
Comprehensive Income [Abstract]
Comprehensive Income
Comprehensive Income (Loss) Note [Text Block]
Compensation and Retirement Disclosure [Abstract]
Concentration Risk Benchmark [Axis]
Concentration Risk Benchmark [Axis]
Concentration Risk Benchmark [Domain]
Concentration Risk Benchmark [Domain]
Regulatory Assets [Member]
Regulatory Assets [Member]
Regulatory Assets.
Deferred Income Taxes [Member]
Deferred Income Taxes [Member]
Deferred Income Taxes.
Net of Tax AOCI [Member]
Net Of Tax AOCI [Member]
Net of Tax Aoci.
Defined Benefit Plans and Other Postretirement Benefit Plans [Axis]
Defined Benefit Plans and Other Postretirement Benefit Plans [Axis]
Defined Benefit Plan and Other Postretirement Benefit Plan [Domain]
Defined Benefit Plan and Other Postretirement Benefit Plan [Domain]
Pension Plans [Member]
Pension Plan [Member]
Qualified Pension Plans [Member]
Qualified Pension Plans [Member]
Qualified Pension Plans.
Nonqualified Pension Plans [Member]
Nonqualified Pension Plans [Member]
Nonqualified Pension Plans.
Other Postretirement Benefit Plans [Member]
Other Postretirement Benefit Plan [Member]
Public Utility [Axis]
Public Utility [Axis]
Utility Plant [Domain]
Utility Plant [Domain]
UMWA Withdrawal Obligation [Member]
UMWA Withdrawal Obligation [Member]
Benefit Payment or Receipt by Type [Axis]
Benefit Payment or Receipt by Type [Axis]
Benefit Payment by Plan Type
Benefit Payment or Receipt by Type [Domain]
Benefit Payment or Receipt by Type [Domain]
[Domain] for Benefit Payment by Plan Type
Pension Payments [Member]
Pension Payments [Member]
Pension Payments.
Benefit Payments [Member]
Benefit Payments [Member]
Benefit Payments.
Medicare Subsidy Receipts [Member]
Medicare Subsidy Receipts [Member]
Medicare Subsidy Receipts.
Accumulated Benefit Obligation
Accumulated Benefit Obligation [Abstract]
Accumulated Benefit Obligation.
Accumulated Benefit Obligation
Defined Benefit Plan, Accumulated Benefit Obligation
Underfunded Accumulated Benefit Obligation
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets [Abstract]
Projected Benefit Obligation
Defined Benefit Plan, Benefit Obligation
Fair Value of Plan Assets
Defined Benefit Plan, Fair Value of Plan Assets
Underfunded Status, Accumulated Benefit Obligation
Underfunded Status, Accumulated Benefit Obligation
The funded status is measured as the difference between the fair value of plan assets and the accumulated benefit obligation.
Estimated Future Benefit Payments and Contributions
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Expected Contributions and Payments During 2017
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year
2017
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months
2018
Defined Benefit Plan, Expected Future Benefit Payments, Year Two
2019
Defined Benefit Plan, Expected Future Benefit Payments, Year Three
2020
Defined Benefit Plan, Expected Future Benefit Payments, Year Four
2021
Defined Benefit Plan, Expected Future Benefit Payments, Year Five
Years 2022 to 2026, in Total
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter
Components of Net Periodic Benefit Cost
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service Cost
Defined Benefit Plan, Service Cost
Interest Cost
Defined Benefit Plan, Interest Cost
Expected Return on Plan Assets
Defined Benefit Plan, Expected Return on Plan Assets
Amortization of Prior Service Cost (Credit)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)
Amortization of Net Actuarial Loss
Defined Benefit Plan, Amortization of Gains (Losses)
Net Periodic Benefit Cost (Credit)
Defined Benefit Plan, Net Periodic Benefit Cost
Capitalized Portion
Capitalized Portion Of Net Periodic Benefit Cost
Capitalized portion of Net Periodic Benefit Cost.
Net Periodic Benefit Cost (Credit) Recognized in Expense
Net Periodic Benefit Cost Recognized as Expense
Net Periodic Benefit Cost recognized as expense.
Estimated Amounts Expected to be Amortized to Net Periodic Benefit Costs
Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year [Abstract]
Net Actuarial Loss
Defined Benefit Plan, Future Amortization of Gain (Loss)
Prior Service Cost (Credit)
Defined Benefit Plan, Future Amortization of Prior Service Cost (Credit)
Total Estimated 2017 Amortization
Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year
Expected to be Recorded as
Expected to be Recorded as [Abstract]
Expected to be Recorded as.
Estimated Amounts Expected to be Amortized to Net Periodic Benefit Costs in 2017
American Electric Power System Retirement Savings Plans
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Cost of Company Matching Contributions
Defined Contribution Plan, Cost Recognized
Benefit Plans Textuals [Abstract]
Benefit Plans Textuals [Abstract]
Benefit Plans.
Matching Contributions Provided Percentage
Matching Contributions Provided Percentage
Matching Contributions Provided Percentage.
Eligible Compensation Contribution by Employee Percentage
Eligible Compensation Contribution By Employee Percentage
Eligible Compensation Contribution by Employee.
Second Matching Contributions Provided Percentage
Second Matching Contributions Provided Percentage
Second Matching Contributions Provided.
Second Eligible Compensation Contribution by Employee Percentage
Second Eligible Compensation Contribution By Employee Percentage
Second Eligible Compensation Contribution By Employee.
Multiemployer Plan Surcharge
Multiemployer Plan Surcharge
Indicates the current employer paid surcharge percentage to the pension plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.
Multiemployer Plans Withdrawal Obligation
Multiemployer Plans, Withdrawal Obligation
Noncurrent Regulatory Assets
Regulatory Assets, Noncurrent
Leases [Abstract]
Segments [Axis]
Segments [Axis]
Segments [Domain]
Segments [Domain]
Sabine Mining Co [Member]
Sabine Mining Co [Member]
Sabine Mining Company Variable Interest Entity Member
AEP Generating Co [Member]
AEP Generating Co [Member]
AEP Generating Company
Major Property Class [Axis]
Major Property Class [Axis]
Major Property Class [Domain]
Major Property Class [Domain]
Rockport Lease [Member]
Rockport Lease [Member]
Lease Type One.
Nuclear Fuel Lease [Member]
Nuclear Fuel Lease [Member]
Lease Type Two.
Railcar Lease [Member]
Railcar Lease [Member]
Lease Type Three.
Boat and Barge Leases [Member]
Boat and Barge Leases [Member]
Boat and Barge Leases [Member]
Sabine Dragline Lease [Member]
Sabine Dragline Lease [Member]
Lease Type Four.
Lease Rental Costs
Lease Rental Costs [Abstract]
Lease Rental Costs.
Net Lease Expense on Operating Leases
Operating Leases, Rent Expense
Amortization of Capital Leases
Capital Leases, Income Statement, Amortization Expense
Interest on Capital Leases
Capital Leases, Income Statement, Interest Expense
Total Lease Rental Costs
Total Lease Rental Costs
Total Lease Rental Costs.
Lease Expenses Related to AEPRO
Disposal Group, Including Discontinued Operation, Total Lease Expenses
Amount classified as lease expenses attributable to disposal group held for sale or disposed of.
PP&E and Related Obligations Under Capital Leases
Property, Plant and Equipment and Related Obligations Under Capital Leases [Abstract]
Generation
Generation Property Plant And Equipment Under Capital Leases
Generation Property Plant And Equipment Under Capital Leases.
Other Property, Plant and Equipment
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Other Property, Plant, and Equipment, Gross
Total Property, Plant and Equipment Under Capital Leases
Capital Leased Assets, Gross
Accumulated Amortization
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation
Net Property, Plant and Equipment Under Capital Leases
Capital Leases, Balance Sheet, Assets by Major Class, Net
Noncurrent Liability
Capital Lease Obligations, Noncurrent
Liability Due Within One Year
Capital Lease Obligations, Current
Total Obligations Under Capital Leases
Capital Lease Obligations
Future Minimum Lease Payments
Future Minimum Lease Payments [Abstract]
Future Minimum Lease Payments.
Capital Leases, 2017
Capital Leases, Future Minimum Payments Due, Next Twelve Months
Noncancelable Operating Leases, 2017
Operating Leases, Future Minimum Payments Due, Next Twelve Months
Capital Leases, 2018
Capital Leases, Future Minimum Payments Due in Two Years
Noncancelable Operating Leases, 2018
Operating Leases, Future Minimum Payments, Due in Two Years
Capital Leases, 2019
Capital Leases, Future Minimum Payments Due in Three Years
Noncancelable Operating Leases, 2019
Operating Leases, Future Minimum Payments, Due in Three Years
Capital Leases, 2020
Capital Leases, Future Minimum Payments Due in Four Years
Noncancelable Operating Leases, 2020
Operating Leases, Future Minimum Payments, Due in Four Years
Capital Leases, 2021
Capital Leases, Future Minimum Payments Due in Five Years
Noncancelable Operating Leases, 2021
Operating Leases, Future Minimum Payments, Due in Five Years
Capital Leases, Later Years
Capital Leases, Future Minimum Payments Due Thereafter
Noncancelable Operating Leases, Later Years
Operating Leases, Future Minimum Payments, Due Thereafter
Capital Leases, Total Future Minimum Lease Payments
Capital Leases, Future Minimum Payments Due
Noncancelable Operating Leases, Total Future Minimum Lease Payments
Operating Leases, Future Minimum Payments Due
Less Estimated Interest Element on Capital Leases
Capital Leases, Future Minimum Payments, Interest Included in Payments
Estimated Present Value of Future Minimum Lease Payments on Capital Leases
Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments
Maximum Potential Loss
Maximum Potential Loss [Abstract]
Maximum potential loss.
Max Potential Loss on Master Lease Agreements
Max Potential Loss on Master Lease Agreements
Maximum potential loss on master lease agreements.
Future Minimum Rentals, Sale Leaseback Transactions
Minimum Lease Payments, Sale Leaseback Transactions, Fiscal Year Maturity [Abstract]
2017
Minimum Lease Payments, Sale Leaseback Transactions, Next Twelve Months
2018
Minimum Lease Payments, Sale Leaseback Transactions, within Two Years
2019
Minimum Lease Payments, Sale Leaseback Transactions, within Three Years
2020
Minimum Lease Payments, Sale Leaseback Transactions, within Four Years
2021
Minimum Lease Payments, Sale Leaseback Transactions, within Five Years
Later Years
Minimum Lease Payments, Sale Leaseback Transactions, Thereafter
Total Future Minimum Lease Payments
Minimum Lease Payments, Sale Leaseback Transactions
Leases (Textuals) [Abstract]
Leases Textuals [Abstract]
Leases Textuals Abstract.
Maximum Remaining Lease Term
Maximum Lease Term
Maximum lease term out of all leases in remaining number of periods.
Lease Term
Lease Term
The term of the lease.
Future Minimum Lease Obligation for Remaining Railcars
Future Min Lease Obligation Remaining Railcars
Future minimum lease obligation for remaining railcars.
Sale Proceeds Guaranteed by Lessor Under Current Five Year Lease Term
Sale Proceeds Guaranteed by Lessor Under Current Five Year Lease Term
Sale proceeds guaranteed by lessor under current five year lease term.
Sale Proceeds Guaranteed by Lessor at the End of 20-Year Term
Sale Proceeds Guaranteed by Lessor at End of Twenty Year Term
Sale proceeds guaranteed by lessor at the end of 20-year term.
Maximum Potential Loss Related to Guarantee
Maximum Potential Loss Related to Guarantee
Maximum potential loss related to the guarantee.
Maximum Potential Lease Payments, AEPRO Barge and Boat Leases
Maximum Potential Lease Payments, AEPRO Barge and Boat Leases
Future potential lease obligations under guaranteed AEPRO boat and barge leases.
Guarantor Obligations, Current Carrying Value
Guarantor Obligations, Current Carrying Value
GuaranteeObligationsCurrentCarryingValueOtherLiabilitiesCurrent
GuaranteeObligationsCurrentCarryingValueOtherLiabilitiesCurrent
The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees recorded under Other Current Liabilities.
GuaranteeObligationsCurrentCarryingValueOtherLiabilitiesNoncurrent
GuaranteeObligationsCurrentCarryingValueOtherLiabilitiesNoncurrent
The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees under Other Noncurrent Liabilities.
Cost of Electric Draglines to be Used for Mining Operations
Cost of Electric Draglines to be Used for Mining Operations
Cost of electric draglines to be used for mining operations.
Portion of Unamortized Nuclear Fuel Inventory Sold at Cost
Portion of Unamortized Nuclear Fuel Inventory Sold at Cost
Portion of unamortized nuclear fuel inventory sold at cost.
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment
Depreciation, Depletion, and Amortization [Policy Text Block]
Asset Retirement Obligations
Asset Retirement Obligations and Environmental Cost, Policy [Policy Text Block]
Related Party Transactions [Abstract]
Affiliated Revenues
Affiliated Revenues [Text Block]
Tabular disclosure of affiliated revenues.
Affiliated Purchases
Affiliated Purchases [Text Block]
Tabular disclosure of affiliated purchases.
Transmission Agreement
Transmission Agreement [Text Block]
Tabular disclosure of Transmission Agreement net charges.
Transmission Coordination Agreement
Transmission Coordination Agreement [Text Block]
Tabular disclosure of Transmission Coordination Agreement net (revenues) expenses.
Coal Transloading
Coal Transloading [Text Block]
Tabular disclosure of OPCo's Cook Coal Terminal - coal transloading.
Railcar Maintenance
Railcar Maintenance Services Table [Text Block]
Tabular disclosure of OPCo's Cook Coal Terminal - railcar maintenance.
Barging, Urea Transloading and Other Services
Barging, Urea Transloading and Other Services [Text Block]
Tabular disclosure of I&M barging, urea transloading and other services.
Central Machine Shop
Central Machine Shop [Text Block]
Tabular disclosure of Central Machine Shop billings from APCo.
Affiliate Railcar Agreement
Affiliate Railcar Agreement [Text Block]
Tabular disclosure of affiliate railcar agreement.
Ownership and Investment in OVEC
Schedule Of Cost Method Ownership And Investments [Table Text Block]
Tabular disclosure of cost method ownership and investments.
Purchased Power from OVEC
Purchased Power from OVEC [Text Block]
Tabular disclosure of purchased power from OVEC.
Related Party Sales of Property
Related Party Sales of Property [Text Block]
Tabular disclosure of related party sales of property.
Related Party Purchases of Property
Related Party Purchases of Property [Text Block]
Tabular disclosure of related party purchases of property.
Share-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]
Award Type [Axis]
Award Type [Axis]
Equity Award [Domain]
Equity Award [Domain]
Stock Based Compensation [Member]
Stock Based Compensation [Member]
Stock Based Compensation
Performance Units [Member]
Performance Units [Member]
Performance Units.
Restricted Shares and Restricted Stock Units [Member]
Restricted Shares and Restricted Stock Units [Member]
Restricted Shares and Restricted Stock Units.
Stock Unit Accumulation Plan for Non Employee Directors [Member]
Stock Unit Accumulation Plan for Non Employee Directors [Member]
Stock Unit Accumulation Plan for Non-Employee Directors.
Stock-based Compensation
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]
Sale Leaseback Transaction, Description [Axis]
Sale Leaseback Transaction, Description [Axis]
Sale Leaseback Transaction, Name [Domain]
Sale Leaseback Transaction, Name [Domain]
Lease Rental Costs
Lease Rental Costs Textblock
Lease Rental Costs.
Property, Plant and Equipment and Related Obligations Under Capital Leases
Property Plant and Equipment and Related Obligations Under Capital Leases [Text Block]
Property, Plant and Equipment and Related Obligations Under Capital Leases.
Future Minimum Lease Payments
Future Minimum Lease Payments [Text Block]
Future Minimum Lease Payments.
Maximum Potential Loss
Max Potential Loss on Master Lease Agreements [Text Block]
Max potential loss on master lease agreements.
Future Minimum Lease Payments
Future Minimum Lease Payments for Sale and Leaseback [Text Block]
Future Minimum Lease Payments for sale-and-leaseback.
Granted Date [Axis]
Granted Date [Axis]
Date the shares were granted
Granted Date [Domain]
Granted Date [Domain]
Granted Date
Granted 2010 [Member]
Granted 2010 [Member]
Granted 2010
Antidilutive Securities [Axis]
Antidilutive Securities [Axis]
Antidilutive Securities, Name [Domain]
Antidilutive Securities, Name [Domain]
Restricted Stock Units (RSUs) [Member]
Restricted Stock Units (RSUs) [Member]
Performance Units and AEP Career Shares Reinvested Dividends Portion For [Member]
Performance Units and AEP Career Shares Reinvested Dividends Portion For [Member]
Performance Units and Career Shares - the related Reinvested Dividends Portion.
Restricted Stock [Member]
Restricted Stock [Member]
Granted Person [Axis]
Granted Person [Axis]
The person who received the shares/units.
Granted Person [Domain]
Granted Person [Domain]
Granted person.
Granted to Previous Chief Executive Officer Succession Candidates [Member]
Granted to Previous Chief Executive Officer Succession Candidates [Member]
Granted to Previous Chief Executive Officer Succession Candidates
Vested Date [Axis]
Vested Date [Axis]
Date the shares were vested
Vesting Date [Domain]
Vesting Date [Domain]
Vesting Date
August 3, 2013 through August 3, 2015 [Member]
August 3, 2013 through August 3, 2015 [Member]
August 3, 2013 through August 3, 2015
Performance Units
Performance units [Abstract]
Performance units.
Awarded Units
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross
Weighted Average Grant Date Fair Value, Granted
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value
Vesting Period (in years)
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period
Vesting Period
Vesting Period
Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.
Certified Performance Scores and Units Earned
Certified Performance Scores And Units Earned [Abstract]
Certified Performance Scores and Units Earned.
Certified Performance Score
Share Based Compensation Certified Performance Score
Certified Performance Score as approved by Human Resources Committee of the Board of Directors.
Performance Units Earned
Share Based Compensation Performance Units Earned
Performance Units Earned.
Performance Units Manditorily Deferred as AEP Career Shares
Share Based Compensation Performance Units Manditorily Deferred As Career Shares
Performance Units Manditorily Deferred as Career Shares
Performance Units Voluntarily Deferred into the Incentive Compensation Deferral Program
Share Based Compensation Performance Units Voluntarily Deferred into Incentive Compensation Deferral Program
Performance Units Voluntarily Deferred into the Incentive Compensation Deferral Program.
Performance Units to be Paid in Cash
Share Based Compensation Performance Units to be Paid in Cash
Performance Units to be Paid in Cash.
Cash Payouts
Cash Payouts [Abstract]
Cash Payouts.
Cash Payouts for Performance Units
Cash Payouts for Performance Units
Cash Payouts for Performance Units.
Cash Payouts for AEP Career Share Distributions
Cash Payouts For Career Share Distributions
Cash Payouts for Career Share Distributions.
Restricted Stock Units Including Units Awarded for Dividends
Rsus including units awarded for dividends [Abstract]
RSUs including units awarded for dividends.
Awarded Units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period
Weighted Average Grant Date Fair Value
Total Fair Value and Total Intrinsic Value of Restricted Shares and Restricted Stock Units Vested
Total fair value and total intrinsic value of restricted shares and restricted stock units vested [Abstract]
Total fair value and total intrinsic value of restricted shares and restricted stock units vested.
Fair Value of Restricted Shares and Restricted Stock Units Vested
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value
Intrinsic Value of Restricted Shares and Restricted Stock Units Vested
Share-based Compensation Arrangement, By Share-based Payment Award, Equity Instruments Other Than Options Vested In Period Total Intrinsic Value
The intrinsic monetary value of equity-based payment equity instruments, excluding stock (or unit) options, that vested during the reporting period as calculated by applying the disclosed pricing methodology.
Status of Nonvested Restricted Shares and Restricted Stock Units
Status of nonvested restricted shares and RSUs [Abstract]
Status of nonvested restricted shares and RSUs.
Nonvested, Shares/Units, Beginning Balance
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number
Nonvested, Weighted Average Grant Date Fair Value, Beginning of Period
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value
Shares/Units, Granted
Shares/Units, Vested
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period
Weighted Average Grant Date Fair Value, Vested
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value
Shares/Units, Forfeited
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period
Weighted Average Grant Date Fair Value, Shares/Units, Forfeited
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value
Nonvested, Shares/Units, Ending Balance
Nonvested, Weighted Average Grant Date Fair Value, End of Period
Stock Unit Accumulation Plan for Non-employee Directors
Stock unit accumulation plan for non employee directors [Abstract]
Stock unit accumulation plan for non-employee directors.
Compensation Cost and Actual Tax Benefit Realized for the Tax Deductions from Compensation Cost for Share-based Payment Arrangements
Compensation cost and actual tax benefit realized [Abstract]
Compensation cost and actual tax benefit realized.
Compensation Cost for Share-based Payment Arrangements
Allocated Share-based Compensation Expense
Actual Tax Benefit Realized
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense
Total Compensation Cost Capitalized
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount
Stock Based Compensation (Textuals) [Abstract]
Stock Based Compensation Textuals [Abstract]
Stock Based Compensation Textuals Abstract.
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant
Number of Shares Remaining Available for Issuance Under the AEP Long-Term Incentive Plan
Common Stock, Capital Shares Reserved for Future Issuance
Reduction in Aggregate Common Shares Authorized Per Share Issued Pursuant to Stock Options or Stock Appreciation Rights
Reduction in Aggregate Common Shares Authorized Per Share Issued Pursuant to Stock Options or Stock Appreciation Rights
Reduction in Aggregate Common Shares Authorized Per Share Issued Pursuant to Stock Options or Stock Appreciation Rights
Performance Score by HR Committee, Lower Range
Performance score by hr Committee lower range
Performance score by HR Committee, lower range.
Performance Score by HR Committee, Higher Range
Performance score by hr Committee higher range
Performance score by HR Committee,higher range.
Maximum Contractual Term of Outstanding Restricted Stock Units (in months)
Maximum Contractual Term of Outstanding Restricted Stock Units
Maximum Contractual Term of Outstanding Restricted Stock Units
Total Aggregate Intrinsic Value of Nonvested Shares
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Intrinsic Monetary Value
The intrinsic monetary value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units, as calculated by applying the disclosed pricing methodology.
Weighted Average Remaining Contractual Life of Nonvested Shares (in years)
Share Based Compensation By Share Based Payment Award Equity Instruments Other Than Options Outstanding Weighted Average Remaining Contractual Terms
Weighted average remaining contractual term for equity-based awards excluding options.
Number of Years After Termination of Board Service Participant Can Elect to Have Stock Units Paid in Cash
Number of Years After Termination of Board Service Participant Can Elect to Have Stock Units Paid in Cash
Number Of Years After Termination Of Board Service Participant Can Elect To Have Stock Units Paid In Cash
Cash Payouts for Stock Unit Accumulation Plan
Cash Payouts for Stock Unit Accumulation Plan
Cash Payouts for Stock Unit Accumulation Plan
Total Unrecognized Compensation Cost Related to Unvested Share-based Compensation Arrangements Granted
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized
Weighted-average Period of Unrecognized Compensation Costs (in years)
Weighted-average Recognization Period for Unrecognized Compensation Costs
Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans.
Income Tax Disclosure [Abstract]
Details of Income Taxes as Reported
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]
Reconciliation of Federal Statutory Tax Rate to Reported Tax Rate
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]
Reconciliation of Significant Temporary Differences
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]
State Net Income Tax Operating Loss Carryforwards
Summary of Operating Loss Carryforwards [Table Text Block]
Summary of Tax Credit Carryforwards
Summary of Tax Credit Carryforwards [Table Text Block]
Summary of Interest Income, Expense And Reversal
Summary Interest Expense Income And Reversal [Text Block]
Table to show summary of amounts reported for interest expense, interest income and reversal of prior period interest expense related to uncertain tax positions.
Amounts Accrued For Interest Related to Uncertain Tax Positions
Amounts Accrued For Interest [Table Text Block]
Table showing balances for amounts accrued for the receipt of interest and the payment of interest and penalties related to uncertain tax positions.
Reconciliation of Beginning and Ending Unrecognized Tax Benefits
Summary of Income Tax Contingencies [Table Text Block]
Unrecognized Tax Benefits Affecting Effective Tax Rate
Unrecognized Tax Benefits That Would Impact Effective Tax Rate [Table Text Block]
Tabular disclosure of the total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in Carrying Amount of Goodwill
Schedule of Goodwill [Table Text Block]
Amortization Life, Gross Carrying Amount and Accumulated Amortization by Major Asset Class
Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block]
Property, Plant and Equipment
Property, Plant and Equipment Disclosure [Text Block]
Stock-based Compensation
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]
Effects of Regulation [Abstract]
Effects of Regulation
Schedule of Regulatory Assets and Liabilities [Text Block]
Debt Disclosure [Abstract]
Financing Activities
Debt Disclosure [Text Block]
Contractual Maturities Year [Axis]
Contractual Maturities Year [Axis]
Contractual Maturities Year Axis.
Contractual Maturities Year [Domain]
Contractual Maturities Year [Domain]
Contractual Maturities Year Domain.
Within One Year [Member]
Within One Year [Member]
Within One Year Member.
One Year To Five Year [Member]
One Year To Five Year [Member]
One Year To Five Year Member.
Five Year To Ten Year [Member]
Five Year To Ten Year [Member]
Five Year To Ten Year Member.
After 10 years [Member]
After 10 years [Member]
After Ten Year Member.
Major Types of Debt and Equity Securities [Axis]
Major Types of Debt and Equity Securities [Axis]
Major Types of Debt and Equity Securities [Domain]
Major Types of Debt and Equity Securities [Domain]
Cash [Member]
Cash [Member]
Fixed Income Funds [Member]
Fixed Income Funds [Member]
Mutual Funds Fixed Income [Member]
Mutual Funds Fixed Income [Member]
Mutual Funds Fixed Income
Equity Securities [Member]
Equity Securities [Member]
Domestic [Member]
Domestic [Member]
Domestic Member.
Mutual Funds Equity [Member]
Mutual Funds Equity [Member]
Mutual Funds Equity
Cash and Cash Equivalents [Member]
Cash and Cash Equivalents [Member]
US Government Agencies Debt Securities [Member]
US Government Agencies Debt Securities [Member]
Corporate Debt Securities [Member]
Corporate Debt Securities [Member]
State and Local Jurisdiction [Member]
State and Local Jurisdiction [Member]
Disposal Group Classification [Axis]
Disposal Group Classification [Axis]
Disposal Group Classification [Domain]
Disposal Group Classification [Domain]
Includes Debt Included In Liabilities Held For Sale [Member]
Includes Debt Included In Liabilities Held For Sale [Member]
A portion of the total amount includes debt included in liabilities held for sale on the balance sheets.
Book Values and Fair Values of Long - term Debt
Long-term Debt, Other Disclosures [Abstract]
Total Long-term Debt Outstanding
Long-term Debt
Long-term Debt, Fair Value
Long-term Debt, Fair Value
Other Temporary Investments
Short-term Investments [Abstract]
Cost
Investment Owned, at Cost
Gross Unrealized Gains
Investment Owned, Unrecognized Unrealized Appreciation
Gross Unrealized Losses
Investment Owned, Unrecognized Unrealized Depreciation
Estimated Fair Value
Short-term Investments
Debt and Equity Securities Within Other Temporary Investments [Abstract]
Debt and Equity Securities Within Other Temporary Investments [Abstract]
Activity for our debt and equity securities within Other Temporary Investments.
Proceeds From Investment Sales
Proceeds from Sale of Short-term Investments
Purchases of Investments
Payments to Acquire Short-term Investments
Gross Realized Gains on Investment Sales
Gross Realized Gains on Investment Sales On Short Term Investment
Gross Realized Gains on Investment Sales On Short Term Investment.
Gross Realized Losses on Investment Sales
Gross Realized Losses On Investment Sales On Short Term Investment
Gross Realized Losses On Investment Sales On Short Term Investment.
Nuclear Trust Fund Investments
Nuclear Trust Fund Investments [Abstract]
Nuclear trust fund investments.
Estimated Fair Value
Spent Nuclear Fuel And Decommissioning Trusts
Funds to pay for the disposal of spent nuclear fuel and the decontaminating and decommissioning of nuclear facilities through the collection of revenues from rate payers.
Gross Unrealized Gains
Gross Unrealized Gains
Gross Unrealized Gains.
Other-Than-Temporary Impairments
Temporary Impairments
Other-Than-Temporary Impairments.
Securities Activity Within the Decommissioning and SNF Trusts
Securities Activity Within Decommissioning and SNF Trusts [Abstract]
Securities Activity Within Decommissioning And Snf Trusts.
Proceeds from Investment Sales
Proceeds From Investment Sales
Proceeds From Investment Sales.
Purchases of Investments
Purchases Of Investments
Purchases of Investments.
Gross Realized Gains on Investment Sales
Gross Realized Gains on Investment Sales
Gross Realized Gains on Investment Sales.
Gross Realized Losses on Investment Sales
Gross Realized Losses On Investment Sales
Gross Realized Losses on Investment Sales.
Contractual Maturities, Fair Value of Debt Securities
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Contractual Maturities, Fair Value of Debt Securities
Fair Value Measurements (Textuals) [Abstract]
Fair Value Measurements (Textuals) [Abstract]
Fair Value Measurements Textuals Abstract
Adjusted Cost of Debt Securities
Adjusted cost of debt securities
Adjusted cost of debt securities.
Adjusted Cost of Domestic Equity Securities
Adjusted Cost Of Equity Securities
Adjusted cost of equity securities within the nuclear trusts
Public Utilities, General Disclosures [Abstract]
Schedule of Income Statement Impact Related to RSR Expenses [Table Text Block]
Schedule of Income Statement Impact Related to RSR and Global Settlement [Table Text Block]
Schedule of Income Statement Impact Related to RSR and Global Settlement [Table Text Block]
Net Income (Loss)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest
OTHER COMPREHENSIVE INCOME
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Cash Flow Hedges, Net of Tax
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax
Securities Available for Sale, Net of Tax
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax
Amortization of Pension and OPEB Deferred Costs, Net of Tax
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax
Pension and OPEB Funded Status, Net of Tax
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)
Other Comprehensive Income (Loss), Net of Tax
TOTAL COMPREHENSIVE INCOME (LOSS)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest
Total Comprehensive Income Attributable to Noncontrolling Interest
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest
TOTAL COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO SHAREHOLDERS
Comprehensive Income (Loss), Net of Tax, Attributable to Parent
Discontinued Operations and Disposal Groups [Abstract]
Corporate and Other [Member]
Corporate and Other [Member]
Generation and Marketing [Member]
Generation And Marketing [Member]
Generation And Marketing [Member]
Assets and Liabilities Held for Sale and Results of Discontinued Operations
Disposal Groups, Including Discontinued Operations [Table Text Block]
Impaired Assets
Impaired Assets [Table Text Block]
Impaired Assets
Related Party Transactions
Related Party Transactions Disclosure [Text Block]
Reclassification out of Accumulated Other Comprehensive Income [Axis]
Reclassification out of Accumulated Other Comprehensive Income [Axis]
Reclassification out of Accumulated Other Comprehensive Income [Domain]
Reclassification out of Accumulated Other Comprehensive Income [Domain]
Reclassifications from Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instrument [Axis]
Derivative Instrument [Axis]
Derivative Contract [Domain]
Derivative Contract [Domain]
Commodity [Member]
Commodity Contract [Member]
Interest Rate [Member]
Interest Rate [Member]
Interest Rate Member.
Equity Components [Axis]
Equity Components [Axis]
Equity Component [Domain]
Equity Component [Domain]
Cash Flow Hedges [Member]
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Securities Available for Sale [Member]
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Pension and OPEB [Member]
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income [Member]
AOCI Attributable to Parent [Member]
Pension and OPEB Activity [Axis]
Pension and OPEB Activity [Axis]
Pension and OPEB activity.
Pension and OPEB Activity [Domain]
Pension and OPEB Activity [Domain]
Pension and OPEB activity.
Amortization of Deferred Costs [Member]
Amortization of Deferred Costs [Member]
Amortization of Deferred Costs on pension and OPEB in Comprehensive Income.
Changes in Funded Status [Member]
Changes in Funded Status [Member]
Changes in funded status on Pension and OPEB in Comprehensive Income.
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Changes In Accumulated Other Comprehensive Income by Component [Abstract]
Beginning Balance in AOCI
Accumulated Other Comprehensive Income (Loss), Net of Tax
Change in Fair Value Recognized in AOCI
Other Comprehensive Income Unrealized Gain Loss Arising During Period Net Of Tax
Net of tax amount, before reclassification adjustments, of the change in accumulated gain (loss).
Reclassifications from Accumulated Other Comprehensive Income (Loss)
Reclassifications From Accumulated Other Comprehensive Income [Abstract]
Gains and Losses on Cash Flow Hedges
Gains And Losses On Cash Flow Hedges [Abstract]
Commodity
Commodity [Abstract]
Commodity.
Vertically Integrated Utilities Revenues
Electric Revenue
Generation & Marketing Revenues
Other Revenue, Net
Purchased Electricity for Resale
Cost of Purchased Power
Other Operation Expense
Utilities Operating Expense, Operations
Maintenance Expense
Utilities Operating Expense, Maintenance
Regulatory Assets/(Liabilities), Net
Reclassifications into Regulatory Assets or Liabilities, Net
Before tax effect of the reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was reclassed to assets / liabilities during the period.
Interest Rate
Interest Rate [Abstract]
Depreciation and Amortization Expense
Utilities Operating Expense, Depreciation and Amortization
Interest Expense
Interest Expense
Pension and OPEB
Amortization Of Pension And Other Postretirement Benefit Plans [Abstract]
Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax
Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax
Income Tax Expense (Benefit)
Income Tax Expense (Benefit)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax
Other Comprehensive Income (Loss), Net of Tax
Pension and OPEB Adjustment Related to Mitchell Plant
Pension and OPEB Adjustment Related to Mitchell Plant
Kentucky Power Company employees operate Mitchell Plant and 50% of Pension and OPEB is related to Nonregulated Generation.
Ending Balance in AOCI
Benefit Plans
Pension and Other Postretirement Benefits Disclosure [Text Block]
Segment Reporting [Abstract]
Business Segments
Segment Reporting Disclosure [Text Block]
Range [Axis]
Range [Axis]
Range [Domain]
Range [Domain]
Minimum [Member]
Minimum [Member]
Maximum [Member]
Maximum [Member]
Balance Sheet Location [Axis]
Balance Sheet Location [Axis]
Balance Sheet Location [Domain]
Balance Sheet Location [Domain]
Actuarial Assumptions for Benefit Obligations
Defined Benefit Plan, Assumptions Used in Calculations [Abstract]
Actuarial Assumptions for Benefit Obligations
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount Rate
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate
Rate of Compensation Increase
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase
Actuarial Assumptions for Net Periodic Benefit Costs
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount Rate
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate
Expected Return on Plan Assets
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets
Rate of Compensation Increase
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase
Health Care Trend Rates
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Initial
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year
Ultimate
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate
Year Ultimate Reached
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate
Effect of a 1% Change in Assumed Health Care Cost Trend Rates for the OPEB Health Care Plans
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
Effect of 1% Increase on Total Service and Interest Cost Components of Net Periodic Postretirement Health Care Benefit Cost
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components
Effect of 1% Decrease on Total Service and Interest Cost Components of Net Periodic Postretirement Health Care Benefit Cost
Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components
Effect of 1% Increase on the Health Care Component of the Accumulated Postretirement Benefit Obligation
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation
Effect of 1% Decrease on the Health Care Component of the Accumulated Postretirement Benefit Obligation
Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation
Projected Plan Obligations, Plan Assets and Funded Status
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Change in Benefit Obligation
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation as of January 1
Actuarial (Gain) Loss
Defined Benefit Plan, Actuarial Gain (Loss)
Benefit Payments
Defined Benefit Plan, Benefits Paid
Participant Contributions
Defined Benefit Plan, Contributions by Plan Participants
Medicare Subsidy
Defined Benefit Plan, Gross Prescription Drug Subsidy Receipts Received
Benefit Obligation as of December 31
Change in Fair Value of Plan Assets
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets as of January 1
Actual Gain (Loss) on Plan Assets
Defined Benefit Plan, Actual Return on Plan Assets
Company Contributions
Defined Benefit Plan, Contributions by Employer
Fair Value of Plan Assets as of December 31
Funded (Underfunded) Status as of December 31
Defined Benefit Plan, Funded Status of Plan
Benefit Amounts Recognized on the Balance Sheets
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Deferred Charges and Other Noncurrent Assets - Prepaid Benefit Costs
Other Assets, Noncurrent
Employee Benefits and Pension Assets - Prepaid Benefit Costs
Defined Benefit Plan, Assets for Plan Benefits, Noncurrent
Other Current Liabilities - Accrued Short-term Benefit Liability
Pension and Other Postretirement Defined Benefit Plans, Current Liabilities
Employee Benefits and Pension Obligations - Accrued Long-term Benefit Liability
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent
Deferred Credits and Other Noncurrent Liabilities - Accrued Long-term Benefit Liability
Other Liabilities, Noncurrent
Funded (Underfunded) Status
Defined Benefit Plan, Amounts Recognized in Balance Sheet
Amounts Included in AOCI and Regulatory Assets
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax [Abstract]
Components
Components [Abstract]
Components.
Net Actuarial Loss
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax
Prior Service Cost (Credit)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax
Recorded as
Recorded as [Abstract]
Recorded as.
Total of Amounts Included in AOCI and Regulatory Assets
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax
Components of Change in Amounts Included in AOCI and Regulatory Assets
Components Of Change In Plan Assets And Benefit Obligations Recognized In Pretax AOCI [Abstract]
Actuarial (Gain) Loss During the Year
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Actuarial Gain (Loss), before Tax
Amortization of Actuarial Gain (Loss)
Amortization of Prior Service Credit (Cost)
Change for the Year
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax
Benefit Plans (Textuals) [Abstract]
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging
Derivative Instruments and Hedging Activities Disclosure [Text Block]
Variable Interest Entities [Abstract]
Variable Interest Entities
Variable Interest Entities [Text Block]
Variable interest entities disclosure
Reportable Segment Information
Schedule of Segment Reporting Information, by Segment [Table Text Block]
Dolet Hills Lignite Co, LLC [Member]
Dolet Hills Lignite Co, LLC [Member]
Dolet Hills Lignite Co, LLC Variable Interest Entity Member
PATH West Virginia Transmission Co, LLC [Member]
PATH West Virginia Transmission Co, LLC [Member]
PATH West Virginia Transmission Co, LLC Variable Interest Entity Member
Target Asset Allocations
Target asset allocations [Text Block]
Target asset allocations for assets in the benefits trusts.
Basic and Diluted EPS Calculations
Earnings Per Share [Text Block]
Supplementary Information
Supplementary Information [Text Block]
Supplementary Information.
Dispositions, Assets and Liabilities Held for Sale and Impairments
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]
Regulation Status [Axis]
Regulation Status [Axis]
Regulated and Unregulated Operation [Domain]
Regulated and Unregulated Operation [Domain]
Regulated Operation [Member]
Regulated Operation [Member]
Unregulated Operation [Member]
Unregulated Operation [Member]
Property, Plant and Equipment
Property, Plant and Equipment [Table Text Block]
Depreciation, Depletion and Amortization
Depreciation, Depletion and Amortization [Text Block]
Depreciation Depletion And Amortization.
Asset Retirement Obligation (ARO)
Schedule of Change in Asset Retirement Obligation [Table Text Block]
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization
Allowance For Funds Used During Construction And Interest Capitalization [Text Block]
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization Text Block.
Jointly-owned Electric Facilities
Schedule of Jointly Owned Utility Plants [Table Text Block]
Variable Interest Entities [Axis]
Variable Interest Entities [Axis]
Variable Interest Entity, Classification [Domain]
Variable Interest Entity, Classification [Domain]
Billings from AEP Service Corporation [Member]
Billings from AEP Service Corporation [Member]
Billings from AEP Service Corporation variable interest entity member.
Carrying Amount in AEP Service Corporation's Accounts Payable [Member]
Carrying Amount in AEP Service Corporation's Accounts Payable [Member]
Carrying amount in AEP Service Corporation's accounts payable member
DCC Fuel [Member]
DCC Fuel [Member]
DCC Fuel Variable Interest Entity Member
Appalachian Consumer Rate Relief Funding [Member]
Appalachian Consumer Rate Relief Funding [Member]
Appalachian Consumer Rate Relief Funding [Member]
Ohio Phase-In-Recovery Funding [Member]
Ohio Phase-In-Recovery Funding [Member]
Ohio Phase-In-Recovery Funding Variable Interest Entity Member
Consolidated Assets And Liabilities Of Variable Interest Entities
Consolidated Assets And Liabilities Of Variable Interest Entities [Table Text Block]
Schedule of consolidated assets and liabilities of variable interest entities.
Companys Investment In Joint Venture
Companys Investment In Joint Venture [Text Block]
Companys investment in joint venture.
Billings from Significant Variable Interest
Billings from Significant Variable Interest [Text Block]
Billings from significant variable interest entity.
Carrying Amount and Classification of Variable Interest in Accounts Payable
Carrying Amount and Classification of Variable Interest in Accounts Payable [Text Block]
The carrying amount and classification of variable interest in accounts payable.
American Electric Power [Member]
Parent Company [Member]
AEP Generation Resources [Member]
AEP Generation Resources [Member]
AEP Generation Resources [Member]
AEP River Operations LLC [Member]
AEP River Operations LLC [Member]
Unaffiliated Parties Two Member.
AEP Subsidiaries [Member]
Subsidiaries [Member]
Kentucky Power Co [Member]
Kentucky Power Co [Member]
Kentucky Power Company Member
Ohio Valley Electric Corporation [Member]
Ohio Valley Electric Corporation [Member]
Ohio Valley Electric Corporation
Wheeling Power Co [Member] [Domain]
Wheeling Power Co [Member] [Domain]
Wheeling Power Co [Member] [Domain]
Related Party [Axis]
Related Party [Axis]
Related Party [Domain]
Related Party [Domain]
Indiana Michigan Power Co to Appalachian Power Co [Member]
Indiana Michigan Power Co to Appalachian Power Co [Member]
Indiana Michigan Power Co to Appalachian Power Co.
Indiana Michigan Power Co to Kentucky Power Co [Member]
Indiana Michigan Power Co to Kentucky Power Co [Member]
Indiana Michigan Power Co to Kentucky Power Co.
Indiana Michigan Power Co to Public Service Co of Oklahoma [Member]
Indiana Michigan Power Co to Public Service Co of Oklahoma [Member]
Indiana Michigan Power Co to Public Service Co of Oklahoma.
Indiana Michigan Power Co to Southwestern Electric Power Co [Member]
Indiana Michigan Power Co to Southwestern Electric Power Co [Member]
Indiana Michigan Power Co to Southwestern Electric Power Co.
Public Service Co of Oklahoma to Appalachian Power Co [Member]
Public Service Co of Oklahoma to Appalachian Power Co [Member]
Public Service Co of Oklahoma to Appalachian Power Co.
Public Service Co of Oklahoma to Indiana Michigan Power Co [Member]
Public Service Co of Oklahoma to Indiana Michigan Power Co [Member]
Public Service Co of Oklahoma to Indiana Michigan Power Co.
Public Service Co of Oklahoma to Southwestern Electric Power Co [Member]
Public Service Co of Oklahoma to Southwestern Electric Power Co [Member]
Public Service Co of Oklahoma to Southwestern Electric Power Co.
Southwestern Electric Power Co to Appalachian Power Co [Member]
Southwestern Electric Power Co to Appalachian Power Co [Member]
Southwestern Electric Power Co to Appalachian Power Co.
Southwestern Electric Power Co to Indiana Michigan Power Co [Member]
Southwestern Electric Power Co to Indiana Michigan Power Co [Member]
Southwestern Electric Power Co to Indiana Michigan Power Co.
Southwestern Electric Power Co to Public Service Co of Oklahoma [Member]
Southwestern Electric Power Co to Public Service Co of Oklahoma [Member]
Southwestern Electric Power Co to Public Service Co of Oklahoma.
AEP Generating Co to Indiana Michigan Power Co [Member]
AEP Generating Co to Indiana Michigan Power Co [Member]
AEP Generating Co to Indiana Michigan Power Co.
AEP Generating Co to Kentucky Power Co [Member]
AEP Generating Co to Kentucky Power Co [Member]
AEP Generating Co to Kentucky Power Co.
AEP Generating Co to Public Service Co of Oklahoma [Member]
AEP Generating Co to Public Service Co of Oklahoma [Member]
AEP Generating Co to Public Service Co of Oklahoma Member.
AEP Generating Co To Southwestern Electric Power Co [Member]
AEP Generating Co To Southwestern Electric Power Co [Member]
AEP Generating Co to Southwestern Electric Power Co.
Types of Related Party Revenue [Axis]
Types of Related Party Revenue [Axis]
Related Party Revenue [Domain]
Related Party Revenue [Domain]
Sales under Interconnection Agreement [Member]
Sales under Interconnection Agreement [Member]
Sales under Interconnection Agreement.
Direct Sales to East Affiliates [Member]
Direct Sales to East Affiliates [Member]
Direct Sales to East Affiliates.
Direct Sales to West Affiliates [Member]
Direct Sales to West Affiliates [Member]
Direct Sales to West Affiliates.
Auction Sales to OPCo [Member]
Auction Sales To OPCo [Member]
Auction Sales to OPCo.
Direct Sales to AEPEP [Member]
Direct Sales to AEPEP [Member]
Direct Sales to AEPEP.
Transmission Agreement and Transmission Coordination Agreement Sales [Member]
Transmission Agreement and Transmission Coordination Agreement Sales [Member]
Transmission Agreement and Transmission Coordination Agreement Sales
Other Revenues [Member]
Other Revenues [Member]
Other Revenues.
Types of Related Party Purchases [Axis]
Types of Related Party Purchases [Axis]
Types of related party purchases.
Related Party Purchases [Domain]
Related Party Purchases [Domain]
Related party purchases.
Purchases under Interconnection Agreement [Member]
Purchases under Interconnection Agreement [Member]
Purchases under Interconnection Agreement.
Direct Purchases from East Affiliates [Member]
Direct Purchases from East Affiliates [Member]
Direct purchases from east affiliates.
Direct Purchases from West Affiliates [Member]
Direct Purchases from West Affiliates [Member]
Direct purchases from west affiliates.
Direct Purchases from AGR [Member]
DirectPurchasesFromAGR [Member]
Direct Purchases From AGR [Member]
Auction Purchases From AEPEP [Member]
Auction Purchases From AEPEP [Member]
Auction Purchases From AEPEP
Auction Purchases From AEP Energy Partners [Member] [Domain]
Auction Purchases From AEP Energy Partners [Member] [Domain]
Auction Purchases From AEP Energy Partners [Member] [Domain]
Direct Purchases from AEPEP [Member]
DirectPurchasesFromAEPEP [Member]
Direct Purchases From AEPEP [Member]
Auction Purchases from AEPSC [Member]
Auction Purchases From AEPSC [Member]
Auction Purchases From AEPSC
Direct Purchases from AEGCo [Member]
Purchases from AEGCo [Member]
Purchases from AEGCo.
Schedule Of Cost Method Investment Cost Method Investee Name [Axis]
Schedule Of Cost Method Investment Cost Method Investee Name [Axis]
Information by investee name in which the entity has an investment accounted for under the cost method of accounting.
Schedule Of Cost Method Investment Cost Method Investee Name [Domain]
Schedule Of Cost Method Investment Cost Method Investee Name [Domain]
Name of each investee in which the entity has an investment accounted for under the cost method of accounting.
Affiliated Revenues and Purchases
Related Party Transaction, Due from (to) Related Party [Abstract]
Affiliated Revenues
Revenue from Related Parties
Cost of Purchased Power from Affiliate
Cost of Purchased Power from Affiliate
Cost of electricity purchased as well as fuel used to generate electricity used in operations and sold during the reporting period from affiliate.
Generation Deferrals
Generation Deferrals
Amount of incurred capacity costs that should be allowed for recovery in the Rate Stabalization Rider (RSR) as part of the "Global Settlement" Joint Stipulation.
Transmission Agreement
Transmission Agreement [Abstract]
Table format showing net charges of Transmission Agreement.
Net Charges from Transmission Agreement
Net Charges Allocated From Transmission Agreement
Net charges allocated to the Registrant Subsidiaries pursuant to the Transmission Agreement.
Transmission Coordination Agreement
Net Charges Credits Allocated Among Parties To Transmission Coordination Agreement [Abstract]
Net Charges (Credits) Allocated Among Parties to Transmission Coordination Agreement Abstract.
Net (Revenues) Expenses from Transmission Coordination Agreement
Net Charges Allocated From Transmission Coordination Agreement
Net charges allocated from Transmission Coordination Agreement.
Cook Coal Terminal
Cook Coal Terminal and SWEPCo Railcar Facility [Abstract]
Cook Coal Terminal and SWEPCo Railcar Facility.
Coal Transloading Services
Coal Transloading Services
Cook Coal Terminal, a division of OPCo, performs coal transloading services at cost.
Railcar Maintenance
Railcar Maintenance
SWEPCo and Cook Coal Terminal, a division of OPCo, perform railcar maintenance services.
Barging, Urea Transloading and Other Services
Barging, Urea Transloading and Other Services [Abstract]
I&M provides barging, urea transloading and other transportation services to affiliates.
Expenses from Barging, Urea Transloading and Other Services
Expenses from Barging, Urea Transloading and Other Services
Expenses from barging, urea transloading and other services provided by I&M.
Central Machine Shop
Central Machine Shop [Abstract]
Central Machine Shop.
Billings for Services from Central Machine Shop Facility
Billings for Services from Central Machine Shop Facility
APCo operates the Central Machine Shop facility which repairs and rebuilds specialized components for the generation plants accross the AEP System.
Affiliate Railcar Agreement
Affiliate Railcar Agreement [Abstract]
Affiliate railcar agreement.
Revenue Related to Affiliate Railcar Agreement
Revenue Related to Affiliate Railcar Agreement
Revenue received from affiliates under the Affiliate Railcar Agreement for the use of each other's leased or owned railcars when available.
Ownership and Investment In OVEC
Ownership And Investment In Ovec [Abstract]
Ownership And Investment In Ohio Valley Electric Corporation
Ownership
Cost Method Investment Ownership Percentage
This item represents the ownership percentage of all cost-method investments.
Investment
Cost Method Investments
Power Purchased by the Registrant Subsidiaries from OVEC
Power Purchased From Ovec [Abstract]
Power purchased by the Registrant Subsidiaries from OVEC.
Amount of Power Purchased from OVEC
Amount Of Power Purchased From O V E C
Amount of power purchased by the Registrant Subsidiaries from OVEC.
Sales and Purchases of Property
Sales and Purchases of Property [Abstract]
Sales and purchases of property with affiliates.
Related Party Sales of Property
Related Party Sales of Property
AEP subsidiaries' sales of property with certain affiliates.
Related Party Purchases of Property
Related Party Purchases of Property
AEP subsidiaries' purchases of property with certain affiliates.
Related Party Transactions (Textuals)
Related Party Transactions (Textuals) [Abstract]
Related Party Transactions Textuals Abstract
Percentage of Power Sold under Unit Power Agreement
Power Agreement Between Subsidiaries In Percent
Percentage of power AEGCo sells to KPCo from both units of the Rockport Plant.
Barge Towing and Chartering Services
Barge Towing and Chartering Services
AEP River Operations LLC provides services for barge towing, chartering and general and administrative expenses to I&M.
Approximate OVEC Generating Capacity (In MWs)
Utility Plant Generation Capacity
Generating capacity of utility plants.
Aggregate Power Participation Ratio
Aggregate Power Participation Ratio
Aggregate Power Participation Ratio
Number of OVEC Generating Plants
Number Of Utility Generation Plants
Number of Utility Generation Plants
Outstanding Indebtedness
Outstanding Indebtedness
Outstanding Indebtedness
Commitments Guarantees and Contingencies [Abstract]
Maturity of Credit Facility [Axis]
Maturity of Credit Facility [Axis]
Maturity of Credit Facility
Maturity of Credit Facility [Domain]
maturityofcreditfacility [Domain]
[Domain] for maturityofcreditfacility [Axis]
June 2017 [Member]
June 2017 [Member]
June 2017
June 2021 [Member]
June 2021 [Member]
June 2021 [Member]
July 2018 [Member]
July 2018 [Member]
July 2018
June 2018 [Member]
June 2018 [Member]
June 2018
Loss Contingency Nature [Axis]
Loss Contingency Nature [Axis]
Loss Contingency, Nature [Domain]
Loss Contingency, Nature [Domain]
Comprehensive Environmental Response Compensation and Liabilities Act and State Remediation [Member]
Superfund and State Remediation [Member]
Superfund and State Remediation Member.
Decommissioning and Low Level Waste Accumulation Disposal [Member]
Decommissioning and Low Level Waste Accumulation Disposal [Member]
Decommissioning and Low Level Waste Accumulation Disposal [Member]
Nuclear Incident Liability [Member]
Nuclear Incident Liability [Member]
Nuclear Incident Liability Member.
Spent Nuclear Fuel Disposal [Member]
Spent Nuclear Fuel Disposal [Member]
Spent Nuclear Fuel Disposal Member
Products and Services [Axis]
Products and Services [Axis]
Products and Services [Domain]
Products and Services [Domain]
Fuel Purchase Contracts [Member]
Fuel Purchase Contracts [Member]
Fuel Purchase Contracts.
Energy and Capacity Purchase Contracts [Member]
Energy and Capacity Purchase Contracts [Member]
Energy and Capacity Purchase Contracts.
Mining Area [Axis]
Mining Area [Axis]
Mining area.
Mining Area [Domain]
Mining Area [Domain]
Mining area.
Guarantor Obligations, Nature [Axis]
Guarantor Obligations, Nature [Axis]
Guarantor Obligations, Nature [Domain]
Guarantor Obligations, Nature [Domain]
Letters of Credit [Member]
Letters of Credit [Member]
Letters of Credit Member.
Guarantees of Third Party Obligations [Member]
Guarantees of Third Party Obligations [Member]
Guarantees of Third Party Obligations Member.
Equity Method Investee [Member]
Guarantees of Equity Method Investees [Member]
Guarantees of Equity Method Investees [Member]
Subsequent Event Type [Axis]
Subsequent Event Type [Axis]
Subsequent Event Type [Domain]
Subsequent Event Type [Domain]
Subsequent Event [Member]
Subsequent Event [Member]
Contractual Commitments
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract]
Less than 1 year
Recorded Unconditional Purchase Obligation Due in Next Twelve Months
For 2-3 years
Recorded Unconditional Purchase Obligation Due Within Two To Three Year
Amount of the recorded unconditional purchase obligation maturing in the next two to three years following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
For 4-5 years
Recorded Unconditional Purchase Obligation Due Within Four To Five Year
Amount of the recorded unconditional purchase obligation maturing in the next four to five years following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
After 5 years
Recorded Unconditional Purchase Obligation Due after Fifth Year
Total Contractual Commitments
Recorded Unconditional Purchase Obligation
Maximum Future Payments for Letters of Credit Under Uncommitted Facilities [Abstract]
Maximum Future Payments for Letters of Credit Under Uncommitted Facilities [Abstract]
Maximum Future Payments for Letters of Credit Under Uncommitted Facilities [Abstract]
Maximum Future Payments for Letters of Credit Issued Under the Uncommitted Facility
Maximum Future Payments for Letters of Credit Issued Under the Uncommitted Facility
Maximum future payments for Letters of Credit issued under the uncommitted facility.
Pollution Control Bonds Supported by Bilateral Letters of Credit [Abstract]
Pollution Control Bonds Supported by Bilateral Letters of Credit [Abstract]
Variable Rate PCBs Supported
Variable Rate PCBs Supported
Amount of Pollution Control Bonds supported by bilateral letters of credit.
Bilateral Letters of Credit
Letters of Credit Outstanding, Amount
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Commitments Guarantees And Contingencies Textuals [Abstract]
Commitments, Guarantees and Contingencies.
Revolving Credit Facilities
Credit Facilities Structured
Amount of revolving credit facilities.
Letters of Credit Limit
Line of Credit Facility, Maximum Borrowing Capacity
Uncommitted Facility
Uncommitted Facility
Amount of letters of credit drawn on an uncommitted credit facility.
Guarantees of Mine Reclamation, Amount
Guarantees Of Mine Reclamation Amount
Guarantees of mine reclamation, amount.
Estimated Final Cost Mine Reclamation
Estimated Final Cost Mine Reclamation
Estimated final cost mine reclamation.
Total Amount Collected through a Rider for Final Mine Closure and Reclamation Costs
Amount Collected Through Rider For Final Mine Closure And Reclamation Costs
Total amount collected through a rider for final mine closure and reclamation costs.
Amount Collected through a Rider for Final Mine Closure - ARO Noncurrent
Amount Collected, Rider Mine Close ARO Noncurrent
Amount collected through a rider for final mine closure and reclamation costs recorded in asset retirement obligations
Amount Collected, Rider Mine Close Other Assets Noncurrent
Amount Collected, Rider Mine Close Other Assets Noncurrent
Amount collected through a rider for final mine closure and reclamation costs recorded in deferred charges and other noncurrent assets.
Maximum Potential Amount of Future Payments Associated with Guarantee
Maximum Potential Amount of Future Payments Associated with Guarantee
Maximum Potential Amount of Future Payments Associated with Guarantee
Expense Recorded Due to Remediation Work Remaining Provision
Environmental Remediation Expense
Cost of Decommissioning and Disposal of Radioactive Waste
Cost of decommissioning and disposal of radioactive waste
Cost of decommissioning and disposal of radioactive waste.
Additional Ongoing Costs for Post Decommissioning Storage of SNF
Additional Ongoing Costs for Post Decommissioning Storage of SNF
Additional Ongoing Costs for Post Decommissioning Storage of SNF
Subsequent Decommissioning of the Spent Fuel Storage Facility
Subsequent Decommissioning of the Spent Fuel Storage Facility
Subsequent Decommissioning of the Spent Fuel Storage Facility
Amount Recovered in Rates for Decommissioning Costs
Amount Recovered In Rates For Decommissioning Costs
Amount recovered in rates for decommissioning costs.
Decommissioning Fund Investments, Fair Value
Decommissioning Fund Investments, Fair Value
Disposal, Assessed Fees and Related Interest
Spent Nuclear Fuel Obligation, Noncurrent
Trust Fund Assets One Time Fee Obligation for Nuclear Fuel Disposition
Trust Fund Assets One Time Fee Obligation for Nuclear Fuel Disposition
Trust fund assets one time fee obligation for nuclear fuel disposition.
Recovery of Spent Nuclear Fuel Storage Costs
Spent Nuclear Fuel Storage Costs Recovery
Recovery of certain spent nuclear fuel dry cask storage costs incurred as a result of the government's delays in accepting SNF for permanent storage.
Current Amount Recoverable from the Federal Government
Settlement Amount Recoverable For Dry Cask Current
Amount expected to be recovered from a governmental agency within one year for settlement of spent fuel disposal litigation.
Noncurrent Amount Recoverable from the Federal Government
Settlement Amount Recoverable For Dry Cask Noncurrent
Amount expected to be recovered from a governmental agency beyond one year for settlement of spent fuel disposal litigation.
Insurance Coverage for Property Damage, Decommissioning and Decontamination
Insurance Coverage For Property Damage Decommissioning And Decontamination
Insurance coverage for property damage, decommissioning and decontamination.
Coverage for Property Damage, Decommissioning and Decontamination for a Nonnuclear Incident
Nonnuclear incident coverage for property damage decommissioning and decontamination
Insurance coverage for property damage, decommissioning and decontamination for a nonnuclear incident.
Contingent Financial Obligation for Mutual Iinsurance
Contingent financial obligation for mutual insurance
Contingent financial obligation for mutual insurance.
Insurance Protection for Public Liability Arising from a Nuclear Incident
Insurance protection for public liability arising from nuclear incident
Insurance protection for public liability arising from a nuclear incident.
Commercially Available Insurance
Commercially available insurance
Commercially available insurance.
Remainder of the Liability Provided by a Deferred Premium Assessment
Remainder of liability provided by deferred premium assessment
Remainder of the liability provided by a deferred premium assessment.
Deferred Premium Assessment Annual Payment
Deferred premium assessment annual payment
Deferred premium assessment annual payment.
Assessed Amount per Nuclear Incident
Assessed amount per nuclear incident
Assessed amount per nuclear incident.
Annual Installments
Annual installments
Annual installments.
Commercially Available Insurance for Catastrophic Nature
Commercially available insurance for catastrophic nature
Commercially available insurance for catastrophic nature.
Commercially Available Insurance for Catastrophic Nature Beginning in 2017
Commercially Available Insurance for Catastrophic Nature Beginning in 2017
Commercially Available Insurance for Catastrophic Nature Beginning in 2017
Liability Coverage Under the Price-Anderson Act
Liability coverage under Price Anderson Act
Liability coverage under the Price-Anderson Act.
Income Statement [Abstract]
Revenues
Revenues [Abstract]
Vertically Integrated Utilities
Transmission and Distribution Utilities
Electrical Transmission and Distribution Revenue
Generation and Marketing
Electrical Generation Revenue
Sales to AEP Affiliates
Other Revenues - Affiliated
Related Party Transaction, Other Revenues from Transactions with Related Party
Other Revenues
TOTAL REVENUES
Revenues
Expenses
Operating Expenses [Abstract]
Fuel and Other Consumables Used for Electric Generation
Electric Production Expense
Purchased Electricity from AEP Affiliates
Amortization of Generation Deferrals
Amortization Of Generation Deferrals
Amortizations related to recoveries of pre-2012 deferred fuel balances are recovered by the Phase In Recover Rider. Amortizations related to recoveries of deferred capacity costs are recovered by the Retail Stability Rider ($1/MWH is the Distribution portion through 5/31/15).
Other Operation
Maintenance
Asset Impairments and Other Related Charges
Other Asset Impairment Charges
Depreciation and Amortization
Taxes Other Than Income Taxes
Taxes, Miscellaneous
TOTAL EXPENSES
Operating Expenses
OPERATING INCOME (LOSS)
Operating Income (Loss)
Other Income (Expense):
Other Nonoperating Income (Expense) [Abstract]
Interest and Investment Income
Investment Income, Net
Interest Income
Investment Income, Interest and Dividend
Carrying Costs Income
Carrying Costs Income
Income recorded to accrue a return on certain regulatory assets as granted by a regulator.
Allowance for Equity Funds Used During Construction
Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity
Interest Expense
INCOME BEFORE INCOME TAX EXPENSE (CREDIT) AND EQUITY EARNINGS (LOSS)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest
Income Tax Expense (Credit)
Equity Earnings (Loss) of Unconsolidated Subsidiaries
Income (Loss) from Equity Method Investments
Income from Continuing Operations
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest
Income from Discontinued Operations, Net of Tax
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest
NET INCOME (LOSS)
Net Income Attributable to Noncontrolling Interests
Net Income (Loss) Attributable to Noncontrolling Interest
EARNINGS ATTRIBUTABLE TO COMMON SHAREHOLDERS
Net Income (Loss) Available to Common Stockholders, Basic
Earnings Per Share
Earnings Per Share [Abstract]
WEIGHTED AVERAGE NUMBER OF BASIC AEP COMMON SHARES OUTSTANDING
Weighted Average Number of Shares Outstanding, Basic
BASIC EARNINGS PER SHARE ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS FROM CONTINUING OPERATIONS
Income (Loss) from Continuing Operations, Per Basic Share
BASIC EARNINGS PER SHARE ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS FROM DISCONTINUED OPERATIONS
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share
TOTAL BASIC EARNINGS PER SHARE ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS
Earnings Per Share, Basic
WEIGHTED AVERAGE NUMBER OF DILUTED AEP COMMON SHARES OUTSTANDING
Weighted Average Number of Shares Outstanding, Diluted
DILUTED EARNINGS PER SHARE ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS FROM CONTINUING OPERATIONS
Income (Loss) from Continuing Operations, Per Diluted Share
DILUTED EARNINGS PER SHARE ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS FROM DISCONTINUED OPERATIONS
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share
TOTAL DILUTED EARNINGS PER SHARE ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS
Earnings Per Share, Diluted
Operating Loss Carryforwards [Table]
Operating Loss Carryforwards [Table]
Income Tax Authority [Axis]
Income Tax Authority [Axis]
Income Tax Authority [Domain]
Income Tax Authority [Domain]
Arkansas [Member]
ARKANSAS
Kentucky [Member]
KENTUCKY
Louisiana [Member]
LOUISIANA
Missouri [Member]
MISSOURI
Oklahoma [Member]
OKLAHOMA
Federal [Member]
Internal Revenue Service (IRS) [Member]
State [Member]
Uk Windfall Tax Issue [Member]
Uk Windfall Tax Issue [Member]
In May 2013 the U.S. Supreme Court decided that the U.K. Windfall Tax imposed upon U.K. electric companies privatized between 1984 and 1996 is a creditable tax for U.S. federal income tax purposes. AEP filed protective claims asserting the creditability of the tax, dependent upon the outcome of the case.
Tax Increase Prevention Act of 2014 [Member]
Tax Increase Prevention Act of 2014 [Member]
Bonus depreciation enacted in the Economic Stimulus Act of 2008, which was extended by the American Recovery and Reinvestment Tax Act of 2009, the American Taxpayer Relief Act of 2012 and the Tax Increase Prevention Act of 2014.
Protecting Americans from Tax Hikes Act of 2015 [Member]
Protecting Americans from Tax Hikes Act of 2015 [Member]
Protecting Americans from Tax Hikes Act of 2015 [Member]
Net Tax Benefit [Member]
Net Tax Benefit [Member]
Net Tax Benefit [Member]
Expiration of Charitable Contribution Carryforward Deductions [Member]
Expiration of Charitable Contribution Carryforward Deductions [Member]
Expiration of Charitable Contribution Carryforward Deductions
Investment in Operations of AEPRO [Member]
Investment in Operations of AEPRO [Member]
Investment in Operations of AEPRO
Sale of AEPRO [Member]
Sale of AEPRO [Member]
Sale of AEPRO
2011 Audit Issue Settlement [Member]
2011 Audit Issue Settlement [Member]
2011 Audit Issue Settlement.
Certain Assets Held for Sale and 2015 Federal Income Tax Return [Member]
Certain Assets Held for Sale and 2015 Federal Income Tax Return [Member]
Certain Assets Held for Sale and 2015 Federal Income Tax Return.
Statement [Line Items]
Operating Loss Carryforwards [Line Items]
Consolidated Income Taxes Before Extraordinary Item
Income Tax Expense (Benefit), Continuing Operations, by Jurisdiction [Abstract]
Federal:
Federal Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current
Current Federal Tax Expense (Benefit)
Deferred
Deferred Federal Income Tax Expense (Benefit)
Deferred Investment Tax Credits
Investment Tax Credit
Total Federal
Federal Income Tax Expense (Benefit), Continuing Operations
State and Local:
State and Local Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current
Current State and Local Tax Expense (Benefit)
Deferred
Deferred State and Local Income Tax Expense (Benefit)
Total State and Local
State and Local Income Tax Expense (Benefit), Continuing Operations
Income Tax Expense:
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current
Current Income Tax Expense (Benefit)
Deferred
Deferred Income Tax Expense (Benefit)
Reconciliation of Federal Income Taxes and Amount of Income Tax Reported
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Net Income
Discontinued Operations
Income Taxes on Pretax Income at Statutory Rate (35%)
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount
Reconciliation of Federal Statutory Rate and Amount of Taxes Reported
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Depreciation
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depreciation, Amount
Depletion
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depletion, Amount
Investment Tax Credits, Net
Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Amount
State and Local Income Taxes, Net
Effective Income Tax Rate Reconciliation, Tax Settlement, State and Local, Amount
Removal Costs
Increase Decrease in Income Taxes Due to Removal Costs
The portion of the difference between total income tax expense (benefit) as reported in the Income Statement and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations due to removal costs.
AFUDC
Increase Decrease In Income Taxes Afudc
The portion of the difference between total income tax expense (benefit) as reported in the Income Statement and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to AFUDC.
Valuation Allowance
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount
Tax Adjustments
Increase Decrease in Income Taxes Due to Tax Reserve Adjustments
The portion of the difference between total income tax expense (benefit) as reported in the Income Statement and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to tax reserve adjustments.
U.K. Windfall Tax
Income Tax Reconciliation UK Windfal lTax
Amount 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 increase (decrease) resulting from the U.K. Windfall Tax.
Other
Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount
Effective Income Tax Rate
Effective Income Tax Rate Reconciliation, Percent
Net Deferred Tax Liability and Significant Temporary Differences
Net Deferred Tax Liability and Significant Temporary Differences [Abstract]
Net deferred tax liability and significant temporary differences.
Deferred Tax Assets
Deferred Tax Assets, Gross
Deferred Tax Liabilities
Deferred Tax Liabilities, Gross
Property Related Temporary Differences
Deferred Tax Assets Liabilities Net Property Related Temporary Differences
The difference between the tax basis and the carrying amount of an asset or liability in the financial statements prepared in accordance with GAAP that will result in taxable amounts in one or more future periods related to property related temporary differences.
Amounts Due from Customers for Future Federal Income Taxes
Amounts Due from Customers for Future Federal Income Taxes
The difference between the tax basis and the carrying amount of an asset or liability in the financial statements prepared in accordance with GAAP that will result in taxable amounts in one or more future periods related to amounts due from customers for future federal income taxes.
Deferred State Income Taxes
Deferred State Income Taxes
Amount of deferred tax liability attributable to taxable temporary differences from state income taxes.
Securitized Assets
Deferred Tax Assets Liabilities Securitized Transition Assets
The difference between the tax basis and the carrying amount of an asset or liability in the financial statements prepared in accordance with GAAP that will result in taxable amounts in one or more future periods related to carrying value of a regulatory asset that represents capitalized stranded costs that have been securitized (financed with debt) and are expected to be recoverable through a transition charge after one year (or beyond the operating cycle if longer).
Regulatory Assets
Deferred Tax Liabilities, Regulatory Assets
Deferred Income Taxes on Other Comprehensive Loss
Deferred Tax Liabilities, Other Comprehensive Income
Impairment Loss
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Impairment Losses
Deferred Federal Income Taxes on Deferred State Income Taxes
Deferred Federal On Recording Deferred State Taxes
Represents the deferred federal income taxes, or the deferred federal income tax impact, associated with the recordation of deferred state income taxes.
Accrued Nuclear Decommissioning
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Asset Retirement Obligations
Deferred Fuel and Purchased Power
Deferred Tax Liabilities, Inventory
Net Operating Loss Carryforward
Deferred Tax Assets, Operating Loss Carryforwards
Tax Credit Carryforward
Deferred Tax Assets, Tax Credit Carryforwards, General Business
Valuation Allowance
Deferred Tax Assets, Valuation Allowance
All Other, Net
All Other, Net
The total of all other differences not specifically indicated elsewhere between the tax basis and the carrying amount of an asset or liability in the financial statements prepared in accordance with GAAP that will result in taxable amounts in one or more future periods.
Net Deferred Tax Liabilities
Deferred Income Tax Liabilities, Net
Net Income Tax Operating Loss Carryforwards
Operating Loss Carryforwards [Abstract]
Operating Loss Carryforwards [Abstract]
Net Income Tax Operating Loss Carryforward
Operating Loss Carryforwards
Operating Loss Carryforwards, Expiration Date
Operating Loss Carryforwards, Expiration Date
Tax Credit Carryforward
Summary of Tax Credit Carryforwards [Abstract]
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
Tax Credit Carryforward, Amount
Tax Credit Carryforward, Amount
Tax Credit Carryforward Amount To Expire If Not Used
Tax Credit Carryforward Amount To Expire If Not Used
The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws that will expire if not used by certain dates.
Summary of Amounts Reported for Interest Expense, Interest Income and Reversal of Prior Period Interest Expense
Summary of Amounts Reported for Interest Expense Interest Income and Reversal of Prior Period Interest Expense [Abstract]
Summary of amounts reported for interest expense, interest income and reversal of prior period interest expense.
Interest Expense
Income Tax Examination, Interest Expense
Interest Income
Income Tax Examination Interest Expense Interest Income
The amount of estimated interest income recognized in the period arising from income tax examinations.
Reversal of Prior Period Interest Expense
Reversal of Prior Period Interest Expense
The amount of prior period interest expense reversal in the period arising from income tax examinations.
Amounts Accrued for Receipt of Interest and Payment of Interest and Penalties
Amounts Accrued For Receipt Of Interest And Payment Of Interest And Penalties [Abstract]
Amounts accrued for receipt of interest and the payment of interest and penalties.
Accrual for Receipt of Interest
Accrual for Receipt of Interest
The amount of estimated receipt of interest accrued as of the balance sheet date arising from income tax examinations.
Accrual for Payment of Interest and Penalties
Income Tax Examination, Penalties and Interest Accrued
Reconciliation of the Beginning and Ending Amount of Unrecognized Tax Benefits
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1,
Unrecognized Tax Benefits
Increase - Tax Positions Taken During a Prior Period
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions
Decrease - Tax Positions Taken During a Prior Period
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions
Increase - Tax Positions Taken During the Current Year
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions
Decrease - Tax Positions Taken During the Current Year
Unrecognized Tax Benefits, Decrease Resulting from Current Period Tax Positions
Decrease - Settlements with Taxing Authorities
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities
Decrease - Lapse of the Applicable Statute of Limitations
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations
Balance at December 31,
Unrecognized Tax Benefits, if Recognized - Amount
Unrecognized Tax Benefits that Would Impact Effective Tax Rate
Income Taxes (Textuals) [Abstract]
Income Taxes (Textuals) [Abstract]
Income Taxes.
Discontinued Operations
Discontinued Operation, Tax Effect of Discontinued Operation
Statutory Tax Rate on Pretax Income
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent
Federal Net Income Tax Operating Loss
Federal Net Income Tax Operating Loss
Federal net income tax operating loss driven by bonus depreciation, pension plan contributions and other temporary differences.
Uncertain Tax Positions Netted Against Operating Loss Carryforward
Uncertain Tax Positions Netted Against Operating Loss Carryforward
Amount of uncertain tax positions netted against the federal net operating loss carryforward tax benefits.
Uncertain Tax Position Noncurrent
Liability for Uncertainty in Income Taxes, Noncurrent
Uncertain Tax Positions Netted Against Tax Credit and Alternative Minimum Tax Carryforward Tax Benefits
Uncertain Tax Positions Netted Against Tax Credit And Alternative Minimum Tax Carryforward
Amount of uncertain tax positions netted against tax credit and alternative minimum tax carryforward tax benefits.
Tax Credit Carryforward, Expiration Date
Tax Credit Carryforward, Expiration Date
Interest Income
Period with No Change in Unrecognized Tax Benefits
Period with No Change in Unrecognized Tax Benefits
Period within which there will be no change in unrecognized tax benefits.
Bonus Depreciation Extension
Bonus Depreciation Economic Stimulus Act
Bonus depreciation enacted in the Economic Stimulus Act of 2008, which was extended by the American Taxpayer Relief Act of 2012, the Tax Increase Prevention Act of 2014 and the Protecting Americans from Tax Hikes Act of 2015.
Bonus Depreciation Extension Phase Down 40
Bonus Depreciation Extension Phase Down 40
Protecting Americans from Tax Hikes Act of 2015 50% bonus depreciation extension phase down to 40% in 2018.
Bonus Depreciation Extension Phase Down 30
Bonus Depreciation Extension Phase Down 30
Protecting Americans from Tax Hikes Act of 2015 bonus depreciation extension phase down to 30% in 2019.
Solar Investment Tax Credit
Solar Investment Tax Credit
Provision in the Protecting Americans from Tax Hikes Act of 2015 to extend the temporary solar tax credit for three years through 2019.
Original Indiana Corporate Income Tax Rate
Original Corporate Income Tax Rate
Original Indiana income tax rate before reduction from legislation passed by the state of Indiana in 2011. Current rate scheduled to be reduced by five one-hundredths of a percent each year beginning after June 30, 2012.
Reduced Indiana Corporate Income Tax Rate
Reduced Corporate Income Tax Rate
Reduced income tax rate resulting from legislation passed by the state of Indiana in 2011. Current rate scheduled to be reduced by five one-hundredths of a percent each year beginning after June 30, 2012.
Reduction In Indiana Corporate Tax Rate
Reduction In Indiana Corporate Tax Rate
Amount by which Indiana corporate income tax rate will decrease in each year beginning after June 30, 2012.
Indiana Corporate Tax Rate
Indiana Corporate Tax Rate
Indiana corporate income tax rate.
Original WV Corporate Income Tax Rate
Reduction In Income Tax Original Rate
West Virginia corporate income tax rate that took effect in 2013 after reduction provided by legislation signed in 2008.
Reduced WV Corporate Income Tax
Reduction In Income Tax New Rate
West Virginia corporate income tax rate to take effect in 2014 after reduction provided by legislation signed in 2008.
Pre-2016 TX Income/Franchise Tax Rate
Pre-2016 TX Income/Franchise Tax Rate
Texas original income/franchise tax rate before reduction passed by House Bill 32 in June 2015.
New TX Income/Franchise Tax Rate
New TX Income/Franchise Tax Rate
Texas income/franchise tax rate to take effect January 1, 2016 after reduction passed by House Bill 32 in June 2015.
Anticipated TX Income/Franchise Tax Rate
Anticipated TX Income/Franchise Tax Rate
Texas income/franchise tax rate anticipated to take effect in 2016 until House Bill 32 passed in June 2015 allowing a reduced tax rate.
Transmission and Distribution Expenses Net Income Adjustment
Transmission and Distribution Expenses Net Income Adjustment
Adjustment to net income for transmission and distribution expenses included in computation of cost of goods sold deduction. This is a result of clarifying guidance regarding the treatment of transmission and distribution expenses included in the computation of taxable income for purposes of calculating the Texas gross margins tax issued by the Texas Comptroller of Public Accounts.
Regulated Operations [Abstract]
Public Utilities General Disclosures [Table]
Public Utilities General Disclosures [Table]
Project [Axis]
Project [Axis]
Project [Domain]
Project [Domain]
Mercury and Air Toxic Standards [Member]
Mercury and Air Toxic Standards [Member]
Mercury and Air Toxic Standards [Member]
Environmental Controls Projects [Member]
Environmental Controls Projects [Member]
Environmental Controls Projects [Member]
Base Rate [Axis]
Base Rate [Axis]
Base Rate Axis.
Base Rate [Domain]
Base Rate [Domain]
Base Rate Domain.
2012 Texas Base Rate Case [Member]
2012 Texas Base Rate Case [Member]
2012 Texas Base Rate Case [Member]
2016 Texas Base Rate Case [Member]
2016 Texas Base Rate Case [Member]
2016 Texas Base Rate Case [Member]
AEP Texas Distribution Cost Recovery Factor [Member]
AEP Texas Distribution Cost Recovery Factor [Member]
AEP Texas Distribution Cost Recovery Factor [Member]
ETT Interim Transmission Rates [Member]
ETT Interim Transmission Rates [Member]
ETT Interim Transmission Rates [Member]
Louisiana 2012 Formula Rate Filing [Member]
Louisiana 2012 Formula Rate Filing [Member]
Louisiana 2012 Formula Rate Filing.
Louisiana 2014 Formula Rate Filing [Member]
Louisiana 2014 Formula Rate Filing [Member]
Louisiana 2014 Formula Rate Filing [Member]
Louisiana 2015 Formula Rate Filing [Member]
Louisiana 2015 Formula Rate Filing [Member]
Louisiana 2015 Formula Rate Filing [Member]
Oklahoma 2015 Base Rate Case [Member]
Oklahoma Base Rate Case - 2015 [Member]
Oklahoma Base Rate Case - 2015 [Member]
SPP Open Access Transmission Tariff Upgrade Costs [Member]
SPP Open Access Transmission Tariff Upgrade Costs [Member]
SPP Open Access Transmission Tariff Upgrade Costs [Member]
TCC and TNC Merger [Member]
TCC and TNC Merger [Member]
TCC and TNC Merger [Member]
TCC Distribution Cost Recovery Factor [Member]
TCC Distribution Cost Recovery Factor [Member]
TCC Distribution Cost Recovery Factor [Member]
TNC Distribution Cost Recovery Factor [Member]
TNC Distribution Cost Recovery Factor [Member]
TNC Distribution Cost Recovery Factor [Member]
Welsh Plant, Units 1 and 3 - Environmental Projects [Member]
Welsh Plant Units 1 And 3 Environmental Projects [Member]
Welsh Plant Units 1 And 3 Environmental Projects [Member]
Comanche Plant [Member]
Comanche Plant [Member]
Comanche Plant [Member]
Northeastern Plant, Unit 3 And Comanche Plant [Member]
Northeastern Plant Unit 3 And Comanche Plant [Member]
Northeastern Plant, Unit 3 and the Comanche Plant [Member]
Northeastern Plant, Unit 3 [Member]
Northeastern Plant, Unit 3 [Member]
Northeastern Plant, Unit 3 [Member]
Northeastern Plant, Unit 4 [Member]
Northeastern Plant Unit 4 [Member]
Northeastern Plant Unit 4 [Member]
Welsh Plant, Units 1 and 3 [Member]
Welsh Plant Unit 1 and 3 [Member]
Welsh Plant Unit 1 and 3 [Member]
Welsh Plant, Unit 2 [Member]
Welsh Plant Unit 2 [Member]
Welsh Plant Unit 2
Public Utilities, General Disclosures [Line Items]
Public Utilities, General Disclosures [Line Items]
Parent Equity Ownership Interest in ETT
Parent Ownership Interest In ETT
Parents equity ownership interest in ETT.
Annual Revenue Requirement Decrease Approved by the PUCT
Annual Revenue Requirement Decrease Approved by the PUCT
ETT's decrease to the annual revenue requirement as approved by the PUCT.
AEP Share of ETT Cumulative Revenues Subject to Review
AEP Share Of ETT Cumulative Revenues Subject To Review
AEP's share of ETT's cumulative revenues, subject to review, based upon interim rate increases received from 2009 through 2015.
Requested Annual Increase
Requested Annual Increase
Requested annual increase.
Requested Base Rate Increase
Requested Base Rate Increase
Requested base rate increase.
Amount Of Increased Depreciation Expense Requested
Amount Of Increased Depreciation Expense Requested
Amount of increased depreciation expense requested.
Amount Of Increase Related To Environmental Controls
Amount Of Increase Related To Environmental Controls
Amount of requested increase related to environmental controls to be installed at certain plants.
Amount Of Requested Increase Related To Environmental Consumable Costs In Fuel Adjustment Clause
Amount Of Requested Increase Related To Environmental Consumable Costs In Fuel Adjustment Clause
Amount of the requested increase related to environmental consumable costs included in the FAC.
Requested Return on Common Equity
Public Utilities, Requested Return on Equity, Percentage
Projected Capital Costs
Projected Capital Costs
Projected capital costs of property, plant and equipment.
Construction Work in Progress
Construction in Progress, Gross
Interim Annual Base Rate Increase
Public Utilities, Interim Rate Increase (Decrease), Amount
Future Incremental Purchased Capacity And Energy Costs Related To Environmental Projects
Future Incremental Purchased Capacity And Energy Costs Related To Environmental Projects
Future incremental purchased capacity and energy costs that will be incurred related to the environmental compliance plan.
Amount Reclassified As Regulatory Assets Upon Retirement Of Plant
Amount Reclassified As Regulatory Assets Upon Retirement Of Plant
Amount reclassified as regulatory assets upon retirement of the plant.
Approved Net Annual Revenue Increase
Approved Net Annual Revenue Increase
Approved net annual revenue increase.
Approved Return on Common Equity
Approved Return on Common Equity
Percentage of public utility's requested return on equity.
2013 Reversal of Previously Recorded Regulatory Disallowances
2013ReversalOfPreviouslyRecordedRegulatoryDisallowances
The 2013 reversal of previously recorded regulatory disallowances.
Resulting Approved Base Rate Increase
Resulting Approved Base Rate Increase
The resulting annual base rate increase subsequent to recent rulings by the PUCT.
Requested Net Increase in Texas Annual Revenues
Requested Net Increase in Texas Annual Revenues
Requested net increase in Texas annual revenues.
Amount of Increase Related to Additonal Investment and Increased Operating Costs
Amount of Increase Related to Additonal Investment and Increased Operating Costs
Amount of requested increase related to additional investment and increased operating costs.
Amount of Increase Related to Transmission Cost Recovery
Amount of Increase Related to Transmission Cost Recovery
Amount of requested increase related to transmission cost recovery.
Amount of Increase Related to Vegetation Management
Amount of Increase Related to Vegetation Management
Amount of increase related to vegetation management.
Louisiana Jurisdictional Share of the Turk Plant
Louisiana Jurisdictional Share Of Turk Plant
Louisiana jurisdictional share of the Turk Plant.
Net Increase in Louisiana Total Rates per the Settlement Agreement
Net Increase In Louisiana Total Rates
Net increase in Louisiana total rates per the settlement agreement.
Base Rate Increase per the Settlement Agreement
Base Rate Increase Per Settlement Agreement
Base rate increase per the settlement agreement.
Fuel Rate Decrease per the Settlement Agreement
Fuel Rate Decrease Per Settlement Agreement
Fuel rate decrease per the settlement agreement.
Return on Common Equity per the Settlement Agreement
Return On Common Equity Per Settlement Agreement
Return on common equity per the settlement agreement.
Reduction to Requested Revenue Increase as Approved in Stipulation Agreement
Reduction To Requested Revenue Increase As Approved In Stipulation Agreement
Reduction to the requested revenue increase as approved by the LPSC in the stipulation agreement.
Additional Requested Annual Increase
Additional Requested Annual Increase
Additional requested annual increase.
Requested Total Annual Increase
Requested Total Annual Increase
Requested total annual increase.
Amount Of Interim Rates Implemented In January 2015 As Approved In Partial Settlement Agreement
Amount Of Interim Rates Implemented In January 2015 As Approved In Partial Settlement Agreement
Amount of interim rates implemented in January 2015, subject to refund, as approved by the LPSC in partial settlement agreement.
Remaining Contractual Construction Obligations
Completed Project Capital Costs
Completed Project Capital Costs
Completed project capital costs.
Amount of Recovery Requested Related to Arkansas Retail Jurisdictional Share of Environmental Costs
Amount of Recovery Requested Related to Arkansas Retail Jurisdictional Share of Environmental Costs
Amount of recovery requested related to Arkansas retail jurisdiction share of environmental costs incurred.
Amount of Additional Recovery Requested Related to Arkansas Retail Jurisdictional Share of Environmental Costs
Amount of Additional Recovery Requested Related to Arkansas Retail Jurisdictional Share of Environmental Costs
Amount of additional recovery requested related to Arkansas retail jurisdiction share of environmental costs incurred.
Total Amount of Recovery Requested Related to Arkansas Retail Jurisdictional Share of Environmental Costs
Total Amount of Recovery Requested Related to Arkansas Retail Jurisdictional Share of Environmental Costs
Total amount of recovery requested related to Arkansas retail jurisdiction share of environmental costs incurred.
Amount of LPSC Approved Eligible Welsh Plant Environmental Control Deferrals
Amount of LPSC Approved Eligible Welsh Plant Environmental Control Deferrals
Amount of LPSC approved eligible Welsh Plant environmental control deferrals.
Amount of LPSC Approved Eligible Welsh Plant Environmental Control Deferred Unrecognized Equity
Amount of LPSC Approved Eligible Welsh Plant Environmental Control Deferred Unrecognized Equity
Amount of LPSC approved eligible Welsh Plant environmental control deferred unrecognized equity.
Property, Plant and Equipment, Net
Public Utilities, Property, Plant and Equipment, Net
Texas Jurisdictional Share of the Welsh Plant
Texas Jurisdictional Share of the Welsh Plant
Texas jurisdictional share of the Welsh Plant.
Annual Credit to Customers Related to Debt Issuance Savings Resulting from Merger
Annual Credit to Customers Related to Debt Issuance Savings Resulting from Merger
Annual credit to customers related to debt issuance savings resulting from AEP Texas merger.
Annual Revenue Requirement Approved in Settlement Agreement
Annual Revenue Requirement Approved in Settlement Agreement
Annual revenue requirement approved in settlement agreement.
Net Unfavorable Impact
Net Unfavorable Impact
Net unfavorable impact.
Income Taxes
Income Tax Disclosure [Text Block]
Commitments, Guarantees and Contingencies
Commitments Contingencies and Guarantees [Text Block]
Statement of Financial Position [Abstract]
Current Assets
Assets, Current [Abstract]
Cash and Cash Equivalents
Cash and Cash Equivalents, at Carrying Value
Other Temporary Investments
Restricted Cash for Securitized Funding
Restricted Cash and Cash Equivalents, Current
Advances to Affiliates
Due from Related Parties, Current
Accounts Receivable:
Accounts Receivable, Net, Current [Abstract]
Customers
Accounts Receivable, Gross, Current
Affiliated Companies
Accounts Receivable, Related Parties, Current
Accrued Unbilled Revenues
Unbilled Receivables, Current
Pledged Accounts Receivable - AEP Credit
Transfers Accounted for as Secured Borrowings, Assets, Carrying Amount
Miscellaneous
Other Receivables
Allowance for Uncollectible Accounts
Allowance for Doubtful Accounts Receivable, Current
Total Accounts Receivable
Accounts Receivable, Net, Current
Fuel
Inventory, Raw Materials, Gross
Materials and Supplies
Other Inventory, Supplies, Gross
Emission Allowances
Emission Allowances
Current Emission Allowances
Risk Management Assets – Nonaffiliated
Derivative Asset, Current
Risk Management Assets - Affiliated
Affiliated Derivative Assets, Current
Fair value, after the effects of master netting arrangements, of an affiliated financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes affiliated assets not subject to a master netting arrangement and not elected to be offset.
Accrued Tax Benefits
Income Taxes Receivable, Current
Regulatory Asset for Under-Recovered Fuel Costs
Regulatory Assets, Current
Accrued Reimbursement of Spent Nuclear Fuel Costs
Accrued Reimbursement of Spent Nuclear Fuel Costs
Accrued reimbursement of spent nuclear fuel costs at Cook nuclear plant. The Department of Energy has an obligation to I&M over the storage of spent nuclear waste.
Margin Deposits
Margin Deposit Assets
Assets Held for Sale
Disposal Group, Including Discontinued Operation, Assets, Current
Prepayments and Other Current Assets
Prepaid Expense and Other Assets, Current
TOTAL CURRENT ASSETS
Assets, Current
Property, Plant and Equipment
Property, Plant and Equipment, Gross [Abstract]
Generation
Public Utilities, Property, Plant and Equipment, Generation or Processing
Transmission
Public Utilities, Property, Plant and Equipment, Transmission
Distribution
Public Utilities, Property, Plant and Equipment, Distribution
Other Property, Plant and Equipment
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment
Total Property, Plant and Equipment
Property, Plant and Equipment, Gross
Accumulated Depreciation and Amortization
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET
Property, Plant and Equipment, Net
Other Noncurrent Assets
Assets, Noncurrent [Abstract]
Notes Receivable - Affiliated
Affiliated Long Term Accounts Notes And Loans Receivable Net Noncurrent
The aggregate of amounts due from affiliates more than one year from the balance sheet date, for goods or services that have been delivered or sold in the normal course of business and an amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money at a future date more than one year from the balance sheet date, reduced to their estimated net realizable fair value by an allowance established by the Company of the amount it deems uncertain of collection and net of any write-downs taken for collection uncertainty on the part of the holder, respectively.
Regulatory Assets
Securitized Assets
Securitized Regulatory Transition Assets, Noncurrent
Spent Nuclear Fuel and Decommissioning Trusts
Goodwill
Goodwill
Long-term Risk Management Assets
Derivative Asset, Noncurrent
Employee Benefits and Pension Assets
Employee Benefits and Pension Assets
Element represents the noncurrent asset recognized on the balance sheet that is associated with employee benefit and pension assets including, but not limited to, defined benefit pension plans, other postretirement defined benefit plans, deferred incentive compensation and other postemployment benefits.
Deferred Charges and Other Noncurrent Assets
TOTAL OTHER NONCURRENT ASSETS
Assets, Noncurrent
TOTAL ASSETS
Assets
Current Liabilities
Liabilities, Current [Abstract]
Advances from Affiliates
Due to Related Parties, Current
Accounts Payable
Accounts Payable, Current
Affiliated Companies
Accounts Payable, Related Parties, Current
Short-term Debt:
Short-term Debt [Abstract]
Securitized Debt for Receivables - AEP Credit
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount
Other Short-term Debt
Short-term Bank Loans and Notes Payable
Total Short-term Debt
Short-term Debt
Long-term Debt Due Within One Year
Long-term Debt, Current Maturities
Risk Management Liabilities
Derivative Liability, Current
Customer Deposits
Customer Deposits, Current
Accrued Taxes
Taxes Payable, Current
Accrued Interest
Interest Payable, Current
Obligations Under Capital Leases
Regulatory Liability for Over-Recovered Fuel Costs
Regulatory Liability, Current
Provision for Refund
Customer Refund Liability, Current
Liabilities Held for Sale
Disposal Group, Including Discontinued Operation, Liabilities, Current
Other Current Liabilities
Other Liabilities, Current
TOTAL CURRENT LIABILITIES
Liabilities, Current
Noncurrent Liabilities
Liabilities, Noncurrent [Abstract]
Long-term Debt
Long-term Debt, Excluding Current Maturities
Long-term Debt - Affiliated
Affiliated Long Term Debt Noncurrent
Sum of the affiliated carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.
Long-term Risk Management Liabilities
Derivative Liability, Noncurrent
Deferred Income Taxes
Deferred Tax Liabilities, Net, Noncurrent
Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory Liability, Noncurrent
Asset Retirement Obligations
Asset Retirement Obligations, Noncurrent
Employee Benefits and Pension Obligations
Employee Benefits and Pension Obligations
Element represents the noncurrent liability recognized on the balance sheet that is associated with employee benefit and pension obligations including, but not limited to, defined benefit pension plans, other postretirement defined benefit plans, deferred incentive compensation and other postemployment benefits.
Obligations Under Capital Leases
Deferred Credits and Other Noncurrent Liabilities
TOTAL NONCURRENT LIABILITIES
Liabilities, Noncurrent
TOTAL LIABILITIES
Liabilities
Rate Matters
Rate Matters
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, environmental requirements). Specifics may include quantifications related to rates, costs and earnings. Events may relate to rate moratoriums or price caps.
Commitments and Contingencies
Commitments and Contingencies
Equity
Stockholders' Equity Attributable to Parent [Abstract]
Common Stock
Common Stock, Value, Issued
Paid-in Capital
Additional Paid in Capital
Retained Earnings
Retained Earnings (Accumulated Deficit)
Accumulated Other Comprehensive Income (Loss)
TOTAL COMMON SHAREHOLDER'S EQUITY
Stockholders' Equity Attributable to Parent
Noncontrolling Interests
Stockholders' Equity Attributable to Noncontrolling Interest
TOTAL EQUITY
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest
TOTAL LIABILITIES AND EQUITY
Liabilities and Equity
Rate Matters
Public Utilities Disclosure [Text Block]
Vertically Integrated Utilities [Member]
Vertically Integrated Utilities [Member]
Vertically Integrated Utilities [Member]
Finite-Lived Intangible Assets by Major Class [Axis]
Finite-Lived Intangible Assets by Major Class [Axis]
Finite-Lived Intangible Assets, Major Class Name [Domain]
Finite-Lived Intangible Assets, Major Class Name [Domain]
Acquired Customer Contracts [Member]
Acquired Customer Contracts [Member]
Acquired customer contracts.
Changes in Carrying Amount of Goodwill
Goodwill [Roll Forward]
Goodwill Total Balance
Impairment Losses
Goodwill, Impairment Loss
Goodwill Written Off Related to Sale of AEPRO
Disposal Group, Including Discontinued Operation, Goodwill
Amortization Life, Gross Carrying Amount and Accumulated Amortization by Major Asset Class
Amortization Life Gross Carrying Amount and Accumulated Amortization by Major Asset Class [Abstract]
Amortization life, gross carrying amount and accumulated amortization by major asset class.
Amortization Life
Finite-Lived Intangible Asset, Useful Life
Gross Carrying Amount
Finite-Lived Intangible Assets, Gross
Accumulated Amortization
Finite-Lived Intangible Assets, Accumulated Amortization
Goodwill and Other Intangible Assets (Textuals) [Abstract]
Goodwill and Other Intangible Assets (Textuals) [Abstract]
Goodwill and Other Intangible Assets Textuals.
Acquired Intangible Assets Subject to Amortization
Finite-lived Intangible Assets Acquired
Amortization of Intangible Assets
Amortization of Intangible Assets
Leases
Leases of Lessee Disclosure [Text Block]
Subsidiaries [Member]
Property, Plant and Equipment, Gross [Abstract]
Common Stock, No Par Value
Common Stock, No Par Value
Common Stock, Par Value Per Share
Common Stock, Par or Stated Value Per Share
Common Stock, Shares Authorized
Common Stock, Shares Authorized
Common Stock, Shares, Issued
Common Stock, Shares, Issued
Common Stock, Shares Outstanding
Common Stock, Shares, Outstanding
Treasury Stock, Shares
Treasury Stock, Shares
AEP Common Stock
Schedule of Stock by Class [Table Text Block]
Long-term Debt
Schedule of Debt [Table Text Block]
Long-term Debt 5-Year Maturity
Schedule of Maturities of Long-term Debt [Table Text Block]
Dividend Payment Restrictions
Dividend Payment Restrictions [Text Block]
Lines of Credit and Short-term Debt
Schedule of Short-term Debt [Table Text Block]
Utility Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Utility Money Pool Participants Money Pool Activity And Authorized Borrowing Limits [Text Block]
Tabular disclosure of a Utility Money Pool participants' money pool activity and authorized borrowing limits including: (1) Maximum Borrowings from Utility Money Pool; (2) Maximum Loans to Utility Money Pool; (3) Average Borrowings from Utility Money Pool; (4) Average Loans to Utility Money Pool; (5) Net Loans (Borrowings) to/from Utility Money Pool as of the balance sheet date; (6) Authorized Short-term Borrowing Limit. The Utility Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain utility subsidiaries.
Nonutility Money Pool Activity
Nonutility Money Pool Activity [Table Text Block]
Tabular disclosure of a Nonutility Money Pool participants' money pool activity including: (1) Maximum Borrowings from Nonutility Money Pool; (2) Maximum Loans to Nonutility Money Pool; (3) Average Borrowings from Nonutility Money Pool; (4) Average Loans to Nonutility Money Pool; (5) Net Loans (Borrowings) to/from Nonutility Money Pool as of the balance sheet date. The Nonutility Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain nonutility subsidiaries.
Maximum and Minimum Interest Rates for Funds Either Borrowed from or Loaned to Utility Money Pool
Maximum And Minimum Interest Rates For Funds Either Borrowed From Or Loaned To Utility Money Pool [Text Block]
Tabular disclosure of the maximum and minimum weighted-average interest rate, calculated on a daily basis, of funds either borrowed from or loaned to a Utility Money Pool during the period. The Utility Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain utility subsidiaries.
Average Interest Rates for Funds Borrowed from and Loaned to Utility Money Pool
Average Interest Rates For Funds Borrowed From And Loaned To Utility Money Pool [Text Block]
Tabular disclosure of the average interest rates for funds borrowed from and loaned to a Utility Money Pool. The Utility Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain utility subsidiaries.
Maximum, Minimum and Average Interest Rates for Funds Borrowed from and Loaned to the Nonutility Money Pool
Maximum Minimum Average Interest Rates for Funds Borrowed from Loaned to Nonutility Money Pool [Text Block]
Tabular disclosure of the maximum and minimum weighted-average interest rate, calculated on a daily basis and the average interest rates of funds borrowed from or loaned to a Nonutility Money Pool during the period.The Nonutility Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain nonutility subsidiaries.
Interest Expense Incurred by Registrant Subsidiaries' for amounts borrowed from the Utility Money Pool
Interest Expense Incurred For Funds Borrowed From Utility Money Pool [Text Block]
Tabular disclosure of interest expense incurred by registrant subsidiaries' for amounts borrowed from the Utility Money Pool. The Utility Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain utility subsidiaries.
Interest Income Earned by Registrant Subsidiaries' for Amounts Advanced to the Utility Money Pool
Interest Income Earned For Funds Loaned To Utility Money Pool [Text Block]
Tabular disclosure of interest income earned by registrant subsidiaries' for amounts advanced to the Utility Money Pool. The Utility Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain utility subsidiaries.
Comparative Accounts Receivable Information
Comparative Accounts Receivable Information [Text block]
Comparative accounts receivable information.
Customer Accounts Receivable Managed Portfolio
Customer Accounts Receivable Managed Portfolio [Text Block]
Customer accounts receivable managed portfolio.
Accounts Receivable and Accrued Unbilled Revenues
Accounts Receivable and Accrued Unbilled Revenues [Text Block]
Accounts receivable and accrued unbilled revenues under the sale of receivables agreement.
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold [Text Block]
Fees paid to AEP Credit for customer accounts receivable sold.
Proceeds on Sale of Receivables to AEP Credit
Proceeds on Sale of Receivables to AEP Credit [Text Block]
Proceeds on sale of receivables to AEP Credit.
Great Plains Energy Inc. [Member]
Great Plains Energy Inc. [Member]
Great Plains Energy Inc. [Member]
Cleco Power, LLC [Member]
Cleco Power, LLC [Member]
Cleco Power LLC Member
SWEPCo's Guarantee Of Debt [Member]
SWEPCo's Guarantee Of Debt [Member]
Swepcos Guarantee Of Debt
Transource Energy [Member]
Transource Energy [Member]
Transource Energy [Member]
Protected Cell Of Energy Insurance Services, Inc. [Member]
Protected Cell Of Energy Insurance Services, Inc. [Member]
Protected Cell Of Energy Insurance Services, Inc. Variable Interest Entity Member
AEP Renewables [Member]
AEP Renewables [Member]
AEP Renewables [Member]
AEP Credit, Inc. [Member]
AEP Credit, Inc. [Member]
AEP Credit, Inc. Variable Interest Entity Member
AEP Texas Central Transition Funding Co [Member]
AEP Texas Central Transition Funding Co [Member]
AEP Texas Central Transition Funding Company Variable Interest Entity Member
Billings from AEP Generating Company [Member]
Billings from AEP Generating Company [Member]
Billings from AEP Generating Company variable interest entity member.
Carrying Amount in AEP Generating Company's Accounts Payable [Member]
Carrying Amount in AEP Generating Company's Accounts Payable [Member]
Carrying amount in AEP Generating Company's accounts payable member.
Current Assets [Member]
Current Assets [Member]
Current Assets
Net Property Plant And Equipment [Member]
Net Property Plant And Equipment [Member]
Net Property Plant And Equipment
Other Noncurrent Assets [Member]
Other Noncurrent Assets [Member]
Total Assets [Member]
Total Assets [Member]
Total Assets
Current Liabilities [Member]
Current Liabilities [Member]
Current Liabilities
Noncurrent Liabilities [Member]
Noncurrent Liabilities [Member]
Noncurrent Liabilities
Equity [Member]
Equity [Member]
Total Liabilities And Equity [Member]
Total Liabilities And Equity [Member]
Total Liabilities And Equity
Capital Contribution From Parent [Member]
Capital Contribution From Parent [Member]
Capital Contribution From Parent
Retained Earnings [Member]
Retained Earnings [Member]
Total Investment [Member]
Total Investment [Member]
Total Investment
Jointly Owned Utility Plant [Axis]
Jointly Owned Utility Plant [Axis]
Jointly Owned Utility Plant [Domain]
Jointly Owned Utility Plant [Domain]
Rockport Generating Plant (Unit No. 1) [Member]
Rockport Generating Plant (Unit No. 1) [Member]
Rockport Generating Plant (Unit No. 2) [Member]
Rockport Generating Plant (Unit No. 2) [Member]
Lawrenceburg Generating Station [Member]
Lawrenceburg Generating Station [Member]
Consolidated Assets and Liabilities of Variable Interest Entities
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
ASSETS
Variable Interest Carrying Amount Assets [Abstract]
Variable Interest Carrying Amount Assets.
Assets
Variable Interest Entity, Consolidated, Carrying Amount, Assets
LIABILITIES AND EQUITY
Variable Interest Carrying Amount Liabilities And Equity [Abstract]
Variable Interest Carrying Amount Liabilities And Equity.
Liabilities and Equity
Variable Interest Carrying Amount Liabilities and Equity
Variable Interest carrying amount liabilities and equity.
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Balance Sheet
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures
Maximum Exposure
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount
Variable Interest Entities (Textuals) [Abstract]
Variable Interest Entities (Textuals) [Abstract]
Billings from VIE
Billings From VIE
Billings from VIE.
Payments Made by I&M to DCC Fuel
Capital lease Payments made
Capital lease payments made by I&M to DCC Fuel.
Securitization Bonds
Secured Debt
Securitized Transition Assets
Minimum Percentage of Equity AEP Provides
Minimum Percentage of Equity AEP Provides
The minimum percentage of equity AEP Parent provides to AEP Credit.
Percentage Of Short Term Borrowing Needs In Excess Of Third Party Financings
Percentage Of Short Term Borrowing Needs In Excess Of Third Party Financings
Percentage of short-term borrowing needs in excess of third party financings provided by AEP to AEP Credit.
Insurance Premium Expense to Protected Cell
Insurance premium expense to protected cell
Insurance premium expense to protected cell.
Equity and Voting Ownership Percentage
Equity and Voting Ownership Percentage
Equity And Voting Ownership Percentage
Proceeds from Partnership Contribution
Proceeds from Partnership Contribution
Intercompany Item Eliminated in Consolidation
Unearned Revenue
Carrying amount as of the balance sheet date of unearned revenue that will be recognized over a future period of time consistent with the repayment of Transition Funding III's bond principal balance.
Percentage of VIE Sales of Lignite Produced
Percentage Of VIE Sales Of Lignite Produced
Percentage of VIE sales of lignite produced.
Percentage of DHLCs Debt Guaranteed by Each SWEPCo and CLECO
Percentage Of VIE Debt Guaranteed
Percentage of DHLCs debt guaranteed by each SWEPCo and CLECO.
Percentage of Management Fee Received by SWEPCo from DHLC
Percentage Of VIE Management Fee Received
Percentage of management fee received by SWEPCo from DHLC.
Percentage of Ownership of Allegheny Series by a Nonaffiliated Company
Percentage of Ownership in subsidiary
Percentage of ownership in Allegheny Series by a nonaffiliated company.
Percentage of Debt Capital Structure in PATH's Stipulation Agreement
Percentage of Debt in PATH's Stipulation Agreement
Percentage of Debt Capital Structure in PATH's Stipulation Agreement
Percentage of Equity Capital Structure in PATH's Stipulation Agreement
Percentage of Equity Capital Structure in PATH's Stipulation Agreement
Percentage of Equity Capital Structure in PATH's Stipulation Agreement
Percentage of Cost of Long Term Debt for PATH's Stipulation Agreement
Percentage of Cost of Long Term Debt for PATH's Stipulation Agreement
Percentage of Cost of Long Term Debt for PATH's Stipulation Agreement
Percentage of PATH WV's Lowered Authorized ROE
Percentage of PATH WV's Lowered Authorized ROE
Percentage of PATH WV's Lowered Authorized ROE based on the January 2017 FERC Order and Initial Decision
Percentage of PATH WV's Previously Authorized ROE
Percentage of PATH WV's Previously Authorized ROE
Percentage of PATH WV's previously authorized ROE prior to the January 2017 FERC order and initial decision.
Jointly Owned Utility Plant, Proportionate Ownership Share
Jointly Owned Utility Plant, Proportionate Ownership Share
Percentage Interest in Rockport Plant Unit 2 Lease
Percentage Interest in Lease
AEGCo's percentage interest in Rockport Plant unit 2 lease.
Advanced Metering Costs [Member]
Over-Recovery of Costs Related to Advanced Metering [Member]
Over-Recovery of Costs Related to Advanced Metering [Member]
Advanced Metering Infrastructure Surcharge [Member]
Advanced Metering Infrastructure Surcharge [Member]
Advanced Metering Infrastructure Surcharge Member.
Advanced Metering System [Member]
Advanced Metering System [Member]
Advanced Metering System [Member]
Amos Plant Transfer Costs - West Virginia [Member]
Amos Plant Transfer Costs - West Virginia [Member]
Amos Plant Transfer Costs - West Virginia [Member]
Asset Removal Costs [Member]
Asset Removal Costs [Member]
Asset Removal Costs Member.
Asset Removal Costs - Tanners Creek Plant Retirement [Member]
Asset Removal Costs - Tanners Creek Plant Retirement [Member]
Asset Removal Costs - Tanners Creek Plant Retirement [Member]
Asset Retirement Obligation [Member]
Asset Retirement Obligation Costs [Member]
Asset Retirement Obligation - Arkansas, Louisiana [Member]
Asset Retirement Obligation - Arkansas, Louisiana [Member]
Asset Retirement Obligation - Arkansas, Louisiana [Member]
Base Plan Funding Costs [Member]
Over-Recovered Base Plan Funding Costs [Member]
Over-Recovered Base Plan Funding Costs [Member]
Basic Transmission Cost Rider [Member]
Basic Transmission Cost Rider [Member]
Basic Transmission Cost Rider [Member]
Capacity Costs - Indiana [Member]
Indiana Under Recovered Capacity Costs [Member]
Carbon Capture and Storage Commercial Scale Facility - West Virginia, FERC [Member]
Carbon Capture and Storage Commercial Scale Facility - West Virginia, FERC [Member]
Carbon Capture and Storage Commercial Scale Facility - West Virginia, FERC [Member]
Carbon Capture and Storage Product Validation Facility [Member]
Product Validation Facility [Member]
Product Validation Facility
Carbon Capture and Storage Product Validation Facility - West Virginia, FERC [Member]
Carbon Capture and Storage Product Validation Facility - West Virginia, FERC [Member]
Carbon Capture and Storage Product Validation Facility - West Virginia, FERC [Member]
Consumer Rate Relief - West Virginia [Member]
Over-Recovered Customer Rate Relief - West Virginia [Member]
Over-Recovered Customer Rate Relief - West Virginia [Member]
Cook Plant Nuclear Refueling Outage Levelization [Member]
Cook Nuclear Plant Refueling Outage Levelization [Member]
Cook Nuclear Plant Refueling Outage Levelization Member.
Cook Plant Turbine [Member]
Cook Plant Turbine [Member]
Cook Plant Turbine [Member]
Cook Plant, Unit 2 Baffle Bolts - Indiana [Member]
Cook Plant, Unit 2 Baffle Bolts - Indiana [Member]
Cook Plant, Unit 2 Baffle Bolts - Indiana [Member]
Cook Plant Uprate Project [Member]
Cook Plant Uprate Project [Member]
Cook Plant Uprate Project [Member]
Deferred Fuel Costs [Member]
Deferred Fuel Costs [Member]
Deferred Investment Tax Credits [Member]
Deferred Investment Tax Credits [Member]
Deferred Investment Tax Credits Member.
Deferred Asset Phase-In Rider [Member]
Deferred Asset Phase In Rider [Member]
Deferred Cook Plant Life Cycle Management Project Costs - Michigan [Member]
Michigan Deferred Cook Plant Life Cycle Management Project Costs [Member]
Michigan Deferred Cook Plant Life Cycle Management Project Costs [Member]
Deferred Cook Plant Life Cycle Management Project Costs - Indiana [Member]
Deferred Cook Plant Life Cycle Management - Indiana [Member]
Deferred Cook Plant Life Cycle Management - Indiana [Member]
Deferred Restructuring Costs - Louisiana [Member]
Deferred Restructuring Costs - Louisiana [Member]
Deferred Restructuring Costs - Louisiana [Member]
Deferred Restructuring Costs - West Virginia [Member]
Deferred Restructuring Costs - West Virginia [Member]
Deferred Restructuring Costs - West Virginia [Member]
Deferred System Reliability Rider Expenses [Member]
Deferred System Reliability Rider Expenses [Member]
Deferred System Reliability Rider Expenses [Member]
Deferred Wind Power Costs [Member]
Deferred Wind Power Costs [Member]
Deferred Wind Power Costs [Member]
Deferred Wind Power Costs - Virginia [Member]
Over-Recovered Deferred Wind Power Costs - Virginia [Member]
Over-Recovered Deferred Wind Power Costs - Virginia [Member]
Distribution Investment Rider [Member]
Under Recovered Distribution Investment Rider [Member]
Economic Development Rider [Member]
Economic Development Rider [Member]
Economic Development Rider.
Energy Efficiency Rate Adjustments Clause - Virginia [Member]
Energy Efficiency Rate Adjustments Clause - Virginia [Member]
Energy Efficiency Rate Adjustments Clause - Virginia [Member]
Enhanced Service Reliability Plan [Member]
Enhanced Service Reliability Plan [Member]
Enhanced Service Reliability Plan.
Excess Asset Retirement Obligations For Nuclear Decommissioning Liability [Member]
Excess Asset Retirement Obligations For Nuclear Decommissioning Liability [Member]
Excess Asset Retirement Obligations For Nuclear Decommissioning Liability Member.
Excess Earnings [Member]
Excess Earnings [Member]
Excess Earnings
Excess Earnings - Texas [Member]
Excess Earnings - Texas [Member]
Excess Earnings - Texas [Member]
Generation Rate Adjustment Clause - Virginia [Member]
Virginia Generation Rate Adjustment Clause [Member]
Virginia Generation Rate Adjustment Clause Regulatory Asset
Generation Recovery Rider Costs - Arkansas [Member]
Over-Recovered Generation Recovery Rider Costs - Arkansas [Member]
Over-Recovered Generation Recovery Rider Costs - Arkansas [Member]
gridSMART Costs [Member]
Gridsmart Costs [Member]
Income Taxes, Net [Member]
Deferred Income Tax Charge [Member]
Integrated Gasification Combined Cycle Preconstruction Costs [Member]
Integrated Gasification Combined Cycle Preconstruction Costs [Member]
Integrated Gasification Combined Cycle Preconstruction Costs - West Virginia, FERC [Member]
Integrated Gasification Combined Cycle Preconstruction Costs - West Virginia, FERC [Member]
Integrated Gasification Combined Cycle Preconstruction Costs - West Virginia, FERC [Member]
Litigation Settlement [Member]
Litigation Settlement [Member]
Litigation Settlement
Louisiana Refundable Construction Financing Costs [Member]
Refundable Construction Financing Costs [Member]
Refundable Construction Financing Costs
Medicare Subsidy [Member]
Statement Of Financial Accounting Standards 106 Medicare Subsidy [Member]
Medicare Subsidy - West Virginia, FERC [Member]
Medicare Subsidy - West Virginia, FERC [Member]
Medicare Subsidy - West Virginia, FERC [Member]
Meter Replacement Costs [Member]
Meter Replacement Costs [Member]
Meter Replacement Costs
Mitchell Plant Transfer [Member]
Mitchell Plant Transfer [Member]
Mitchell Plant Transfer [Member]
Off-system Sales Margin Sharing - Indiana [Member]
Indiana Off-system Sales Margin Sharing [Member]
Indiana Off-system Sales Margin Sharing [Member]
Ohio Capacity Deferral [Member]
Ohio Capacity Deferral [Member]
Ohio Capacity deferral.
Ohio Distribution Decoupling [Member]
Distribution Decoupling [Member]
Ohio Distribution Decoupling.
Ohio Transmission Cost Recovery Rider [Member]
Transmission Cost Recovery Rider [Member]
Transmission Cost Recovery Rider Member.
Other Regulatory Assets Approved for Recovery [Member]
Other Regulatory Assets Being Recovered [Member]
Other Regulatory Assets Being Recovered
Other Regulatory Assets Pending Final Regulatory Approval [Member]
Other Regulatory Assets Not Yet Being Recovered [Member]
Other Regulatory Assets Not Yet Being Recovered
Other Regulatory Liabilities Approved for Payment [Member]
Other Regulatory Liabilities Being Paid [Member]
Other Regulatory Liabilities Being Paid
Other Regulatory Liabilities Pending Final Regulatory Determination [Member]
Other Regulatory Liabilities Not Yet Being Paid [Member]
Other Regulatory Liabilities Not Yet Being Paid Member.
OVEC Purchased Power [Member]
OVEC Purchased Power [Member]
OVEC Purchased Power [Member]
Partnership with Ohio Contribution [Member]
Partnership With Ohio Contribution [Member]
Peak Demand Reduction/Energy Efficiency [Member]
Energy Efficiency/Peak Demand Reduction [Member]
Energy Efficiency/Peak Demand Reduction.
Peak Demand Reduction/Energy Efficiency - Virginia [Member]
Peak Demand Reduction/Energy Efficiency - Virginia [Member]
Peak Demand Reduction/Energy Efficiency - Virginia [Member]
Peak Demand Reduction/Energy Efficiency - West Virginia [Member]
Peak Demand Energy Efficiency West Virginia [Member]
Peak Demand Energy Efficiency West Virginia [Member]
Pension Costs [Member]
Pension Costs [Member]
PJM Expense - Indiana [Member]
PJM Expense - Indiana [Member]
PJM Expense - Indiana [Member]
Plant Retirement Costs - Asset Retirement Obligation Costs [Member]
Asset Retirement Obligation Related to Retired Plants [Member]
Asset Retirement Obligation Related to Retired Plants [Member]
Plant Retirement Costs - Materials and Supplies [Member]
Materials and Supplies Related to Retired Plants [Member]
Materials and Supplies Related to Retired Plants [Member]
Plant Retirement Costs - Unrecovered Plant [Member]
Plant Retirement Costs - Unrecovered Plant [Member]
Plant Retirement Costs - Unrecovered Plant [Member]
Postemployment Benefits [Member]
Postemployment Benefits [Member]
Postemployment Benefits
Provision for Regulatory Loss [Member]
Provision for Regulatory Loss [Member]
Provision for Regulatory Loss [Member]
Rate Case Expense [Member]
Rate Case Expense [Member]
Rate Case Expense.
Rate Case Expense - Texas [Member]
Rate Case Expense - Texas [Member]
Rate Case Expense - Texas [Member]
Red Rock Generating Facility [Member]
Red Rock Generating Facility [Member]
Red Rock Generating Facility Member.
Regional Transmission Organization Formation/Integration Costs [Member]
Regional Transmission Organization Formation/Integration Costs [Member]
Regional Transmission Organization Formation/Integration Costs
Regulatory Settlement [Member]
Regulatory Settlement [Member]
Regulatory Settlement [Member]
River Transportation Division Expenses [Member]
River Transportation Division Expenses [Member]
River Transportation Division Expenses.
Rockport Plant Dry Sorbent Injection System - Indiana [Member]
Rockport Plant Dry Sorbent Injection System - Indiana [Member]
Rockport Plant Dry Sorbent Injection System - Indiana [Member]
Shipe Road Transmission Project - FERC [Member]
Shipe Road Transmission Project [Member]
Shipe Road Transmission Project [Member]
Spent Nuclear Fuel Liability [Member]
Spent Nuclear Fuel Liability [Member]
Spent Nuclear Fuel Liability
Storm Related Costs [Member]
Storm Costs [Member]
Storm Related Costs - Indiana [Member]
Storm Related Costs - Indiana [Member]
Storm Related Costs - Indiana [Member]
Storm Related Costs - Virginia [Member]
Storm Related Costs - Virginia [Member]
Storm Related Costs - Virginia [Member]
Storm Related Costs - West Virginia [Member]
Storm Related Costs - West Virginia [Member]
Storm Related Costs - West Virginia [Member]
Stranded Costs on Abandoned Plants [Member]
Stranded Costs On Abandoned Plants [Member]
SPP Base Plan Fees [Member]
SPP Base Plan Fees [Member]
SPP Base Plan Fees [Member]
Tanners Creek Plant Units 1 Through 4 [Member]
Tanners Creek Plant Units 1 Through 4 [Member]
Tanners Creek Plant, Units 1-4
Texas Meter Replacement Costs [Member]
Transition Charges [Member]
Stranded Costs [Member]
Transmission Agreement Phase-In - West Virginia [Member]
Transmission Agreement Phase-In - West Virginia [Member]
Transmission Agreement Phase-In - West Virginia [Member]
Transmission Cost Recovery Factor [Member]
Under-Recovery of Transmission Cost Recovery Factor [Member]
Transmission Rate Adjustment Clause - Virginia [Member]
Transmission Rate Adjustment Clause [Member]
Transmission Rate Adjustment Clause Regulatory Asset
Unamortized Loss on Reacquired Debt [Member]
Loss on Reacquired Debt [Member]
Uncollected Accounts - West Virginia [Member]
Uncollected Accounts - West Virginia [Member]
Uncollected Accounts - West Virginia [Member]
United Mine Workers of America Pension Withdrawal [Member]
United Mine Workers of America Pension Withdrawal [Member]
Unrealized Gain on Forward Commitments [Member]
Unrealized Gain on Forward Commitments [Member]
Unrealized Gain on Forward Commitments Member.
Unrealized Loss on Forward Commitments [Member]
Unrealized Loss on Forward Commitments [Member]
Unrealized Loss on Forward Commitments
Vegetation Management [Member]
Vegetation Management [Member]
Vegetation Management Member.
Vegetation Management Program - West Virginia [Member]
West Virginia Vegetation Management Program [Member]
West Virginia Vegetation Management Program [Member]
Welsh Plant, Unit 2 [Member]
West Virginia Delayed Customer Billing [Member]
West Virginia Delayed Customer Billing [Member]
West Virginia Delayed Customer Billing [Member]
Regulatory Assets Currently Return [Axis]
Regulatory Assets Currently Return [Axis]
Regulatory Assets Currently Return Axis.
Regulatory Assets Current Return [Domain]
Regulatory Assets Currently Return [Domain]
Regulatory Assets Currently Return Domain.
Regulatory Assets Currently Earning a Return [Member]
Regulatory Assets Currently Earning Return [Member]
Regulatory Assets Currently Earning a Return
Regulatory Assets Currently Not Earning a Return [Member]
Regulatory Assets Currently Not Earning Return [Member]
Regulatory Assets Currently Not Earning a Return
Regulatory Asset [Axis]
Regulatory Asset [Axis]
Regulatory Asset [Domain]
Regulatory Asset [Domain]
Regulatory Assets Pending Final Regulatory Approval [Member]
Regulatory Assets Not Yet Being Recovered [Member]
Regulatory Assets Not Yet Being Recovered
Regulatory Assets Approved for Recovery [Member]
Regulatory Assets Being Recovered [Member]
Regulatory Assets Being Recovered Member.
Regulatory Liabilities [Axis]
Regulatory Liabilities [Axis]
Regulatory Liabilities Axis.
Regulatory Liabilities [Domain]
Regulatory Liabilities [Domain]
Regulatory Liabilities Domain.
Regulatory Liabilities Currently Not Paying Return [Member]
Regulatory Liabilities Currently Not Paying Return [Member]
Regulatory Liabilities Currently Not Paying Return Member.
Regulatory Liabilities Currently Paying a Return [Member]
Regulatory Liabilities Currently Paying Return [Member]
Regulatory Liabilities Currently Paying Return Member.
Regulatory Liability [Axis]
Regulatory Liability [Axis]
Regulatory Liability [Domain]
Regulatory Liability [Domain]
Regulatory Liabilities Approved for Payment [Member]
Regulatory Liabilities Being Paid [Member]
Regulatory Liabilities Being Paid Member.
Regulatory Liabilities Pending Final Regulatory Determination [Member]
Regulatory Liabilities Not Yet Being Paid [Member]
Regulatory Liabilities Not Yet Being Paid
Regulatory Assets
Regulatory assets are comprised [Abstract]
Regulatory assets are comprised Abstract.
Current Regulatory Assets
Remaining Recovery Period
Regulatory Asset, Amortization Period
Regulatory Liabilities
Regulatory liabilities are comprised [Abstract]
Regulatory liabilities are comprised Abstract.
Current Regulatory Liabilities
Noncurrent Regulatory Liabilities
Remaining Refund Period
Regulatory Liability, Amortization Period
Lease, Policy [Policy Text Block]
Lease, Policy [Policy Text Block]
Quarterly Financial Information Disclosure [Abstract]
Summary of Unaudited Quarterly Financial Information
Selected Quarterly Financial Information [Abstract]
Total Revenues
Operating Income (Loss)
Income (Loss) from Continuing Operations
Income (Loss) from Discontinued Operations, Net of Tax
Amounts Attributable to AEP Common Shareholders
Net Income (Loss) Available to Common Stockholders, Basic [Abstract]
Earnings (Loss) Attributable To AEP Common Shareholders
Basic Earnings (Loss) per Share Attributable to AEP Common Shareholders:
Earnings Per Share, Basic [Abstract]
Basic Earnings (Loss) per Share Attributable to AEP Common Shareholders from Continuing Operations
Basic Earnings (Loss) per Share Attributable to AEP Common Shareholders from Discontinued Operations
Total Basic Earnings (Loss) Per Share Attributable to AEP Common Shareholders
Diluted Earnings (Loss) per Share Attributable to AEP Common Shareholders:
Earnings Per Share, Diluted [Abstract]
Diluted Earnings (Loss) per Share Attributable to AEP Common Shareholders from Continuing Operations
Diluted Earnings (Loss) per Share Attributable to AEP Common Shareholders from Discontinued Operations
Total Diluted Earnings (Loss) Per Share Attributable to AEP Common Shareholders
Actuarial Assumption Financial Statement Effect [Axis]
Actuarial Assumption Financial Statement Effect [Axis]
Actuarial Assumption Financial Statement Effect.
Actuarial Assumption Financial Statement Effect [Domain]
Actuarial Assumption Financial Statement Effect [Domain]
[Domain] for Actuarial Assumption Financial Statement Effect.
Benefit Obligations [Member]
Benefit Obligations [Member]
Benefit Obligations Member
Benefit Costs [Member]
Benefit Costs [Member]
Benefit Costs Member
Actuarial Assumptions
Schedule of Assumptions Used [Table Text Block]
Health Care Trend Rates
Schedule of Health Care Cost Trend Rates [Table Text Block]
Effect of a 1% Change in Assumed Health Care Cost Trend Rates for the OPEB Health Care Plans
Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block]
Reconciliation of Changes in Benefit Obligations and Fair Value of Assets
Schedule of Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]
Benefit Amounts Recognized on the Balance Sheets
Schedule of Amounts Recognized in Balance Sheet [Table Text Block]
Amounts Included in AOCI and Regulatory Assets
Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block]
Components of Change in Amounts Included in AOCI and Regulatory Assets
Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block]
Allocated Assets of Investments
Allocated Assets of Investments [Table Text Block]
Tabular disclosure of the percentage of investments that are allocated to the Registrant Subsidiaries.
Assets within Fair Value Hierarchy
Schedule of Allocation of Plan Assets [Table Text Block]
Pension Plan Assets Level 3 Reconciliation
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
Accumulated Benefit Obligation
Accumulated Benefit Obligation [Text Block]
Table containing the Accumulated Benefit Obligation as a single block of text.
Underfunded Accumulated Benefit Obligation
Schedule of Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]
Estimated Contributions and Payments to the Pension and OPEB Plans
Schedule Of Estimated Contributions And Payments To Pension And O P E B Plans [Text Block]
Tabular disclosure of the expected contributions and payments expected to be paid to the pension plans and/or other employee benefit plans in the next fiscal year.
Estimated Payments Expected to be Made by the Pension and OPEB Plans
Schedule of Expected Benefit Payments [Table Text Block]
Components of Net Periodic Benefit Cost
Schedule of Net Benefit Costs [Table Text Block]
Estimated Amounts to be Amortized to Net Periodic Benefit Costs
Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [Table Text Block]
Cost for Matching Contributions to the Retirement Savings Plans
Schedule of Costs of Retirement Plans [Table Text Block]
Quarterly Financial Information
Quarterly Financial Information [Text Block]
Changes in Accumulated Other Comprehensive Income (Loss) by Component
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]
Income Tax Policy
Income Tax, Policy [Policy Text Block]
Notional Volume of Derivative Instruments
Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]
Cash Collateral Netting
Cash Collateral Netting [Text Block]
Tabular disclosure of cash collateral netting.
Fair Value of Derivative Instruments
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Schedule of Derivative Instruments Included in Trading Activities [Table Text Block]
Gain (Loss) on Hedging Instruments
Derivative Instruments, Gain (Loss) [Table Text Block]
Impact of Cash Flow Hedges on the Balance Sheet
Impact of Cash Flow Hedges on Balance Sheet [Text Block]
Tabular disclosure of the impact of cash flow hedges on the balance sheet.
Collateral Required Under Various Triggering Events
Collateral Required [Text Block]
Tabular disclosure of the collateral required under various triggering events.
Liabilities Subject to Cross Default Provisions
Cross Default Provision [Text Block]
Tabular disclosure of liabilities subject to cross default provisions.
Restricted Stock Units [Member]
Restricted Stock Units [Member]
International [Member]
International [Member]
International Member.
Defined Benefit Plan, Asset Categories [Axis]
Defined Benefit Plan, Asset Categories [Axis]
Plan Asset Categories [Domain]
Plan Asset Categories [Domain]
Fixed Income [Member]
Fixed Income Securities [Member]
Other Investments [Member]
Other Investments [Member]
Debt Instrument [Axis]
Debt Instrument [Axis]
Debt Instrument, Name [Domain]
Debt Instrument, Name [Domain]
Other Long Term Debt [Member]
Other Long Term Debt [Member]
Other long term debt member
Pollution Control Bonds [Member]
Pollution Control Bonds [Member]
Pollution Control Bonds Member.
Generation Assets Carrying Amounts [Abstract]
Generation Assets Carrying Amounts [Abstract]
Assets
Assets [Abstract]
Current Assets
Property, Plant and Equipment, Net
Other Noncurrent Assets
TOTAL ASSETS
Liabilities and Equity
Liabilities and Equity [Abstract]
Long-term Debt
Other Liabilities, Noncurrent
Equity
TOTAL LIABILITIES AND EQUITY
Target Asset Allocations
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target Asset Allocation
Defined Benefit Plan, Target Plan Asset Allocations
Basic and Diluted EPS Calculations
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest
Net Income (Loss) Attributable to Noncontrolling Interests
Income (Loss) from Continuing Operations Attributable to Parent
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent
Weighted Average Number of Basic AEP Common Shares Outstanding
Weighted Average Dilutive Effect of:
Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]
Weighted Average Dilutive Effect of Shares
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements
Dilutive Securities, Effect on Basic Earnings Per Share
Dilutive Securities 1
Includes adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.
Weighted Average Number of Diluted AEP Common Shares Outstanding
Supplementary Information
Supplementary Information [Abstract]
Supplementary Information.
Related Party Transactions [Abstract]
AEP Consolidated Revenues - Other Revenues:
Parent Companys Consolidated Revenues Other Revenues [Abstract]
Parent Companys Consolidated Revenues Other Revenues.
Ohio Valley Electric Corporation - Barging and Other Transportation Services (43.47% Owned)
AEP Consolidated Expenses - Purchased Electricity for Resale:
Parent Company Consolidated Expenses Purchased Electricity For Resale [Abstract]
Parent Company Consolidated Expenses Purchased Electricity For Resale.
Ohio Valley Electric Corporation (43.47% Owned)
Related Party Transaction, Expenses from Transactions with Related Party
Supplemental Income Statement Elements [Abstract]
Supplemental Income Statement Elements [Abstract]
Depreciation and Amortization of Property, Plant and Equipment
Depreciation
Amortization of Certain Securitized Assets
Amortization of Certain Securitized Assets
The expense charged against earnings during the period to allocate the capitalized costs of securitized assets over the periods expected to benefit from such costs.
Amortization of Regulatory Assets and Liabilities
Amortization of Regulatory Assets and Liabilities
The expense/income charged against earnings during the period to allocate the capitalized costs of regulatory assets/liabilities over the periods expected to benefit from such costs.
Utilities Operating Expense, Depreciation and Amortization
Cash Flow Information
Supplemental Cash Flow Information [Abstract]
Cash Paid (Received) for:
Cash Paid Received for [Abstract]
Cash Paid (Received) for.
Interest Paid, Net
Interest Paid, Net
Income Taxes Paid, Net
Income Taxes Paid, Net
Noncash Investing and Financing Activities:
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Capital Lease Obligations Incurred
Capital Lease Obligations Incurred
Construction Expenditures Included in Current Liabilities as of December 31,
Construction in Progress Expenditures Incurred but Not yet Paid
Construction Expenditures Included in Noncurrent Liabilities as of December 31,
Capital Expenditures Incurred but Not yet Paid
Construction Expenditures Included in Noncurrent Assets as of December 31,
Noncash or Part Noncash Acquisition, Fixed Assets Acquired
Acquisition of Nuclear Fuel Included in Current Liabilities as of December 31,
Acquisition Of Nuclear Fuel Included In Current Liabilities
Future cash outflow to pay for acquired nuclear fuel.
Expected Reimbursement For Spent Nuclear Fuel Dry Cask Storage
Expected Reimbursement For Spent Nuclear Fuel Dry Cask Storage
Future cash inflow for nuclear fuel dry cask storage reimbursement from the DOE.
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Organization and Summary of Significant Accounting Policies Textuals [Abstract]
Organization and Summary of Significant Accounting Policies.
Issuance of Long-term Debt
Proceeds from Issuance of Long-term Debt
Repayments of Long-term Debt
Repayments of Long-term Debt
Antidilutive Shares Outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount
AEP's Ownership in OVEC
AEP's Investment in OVEC
Supplemental Agreement During the Period Between Parties to Interconnection Agreement and OVEC
Pension and Other Postretirement Plans
Pension and Other Postretirement Plans, Policy [Policy Text Block]
Mutual Funds Equity [Member]
Mutual Fund [Member]
Hedging Relationship [Axis]
Hedging Relationship [Axis]
Hedging Relationship [Domain]
Hedging Relationship [Domain]
Risk Management Commodity Contracts [Member]
Risk Management Commodity Contracts [Member]
Risk Management Contracts Member.
Energy Contracts [Member]
Energy Contracts [Member]
Risk management commodity contracts whose primary underlying risk is tied energy contracts.
FTRs [Member]
Financial Trasnsmission Rights [Member]
Risk management commodity contracts whose primary underlying risk is tied financial transmission rights.
Commodity [Member]
Commodity [Member]
Interest Rate Foreign Currency Hedges [Member]
Interest Rate Foreign Currency Hedges [Member]
Fair Value Hedging [Member]
Fair Value Hedging [Member]
Maturity of Fair Value Risk Management Contracts [Axis]
Maturity Of Fair Value Risk Management Contracts Abstract [Axis]
Maturity Year [Domain]
Maturity Year [Domain]
2016 [Member]
Maturity Period One [Member]
2017 [Member]
Maturity Period Two [Member]
2017 - 2019 [Member]
Maturity Period Three [Member]
2018 - 2020 [Member]
Maturity Period Four [Member]
2020 - 2021 [Member]
Maturity Period 5 [Member]
2021 - 2022 [Member]
Maturity Period Six [Member]
2022 - 2032 [Member]
Maturity Period Seven [Member]
2023 - 2032 [Member]
Maturity Period Eight [Member]
Maturity Period Eight.
Fair Value, Hierarchy [Axis]
Fair Value, Hierarchy [Axis]
Fair Value Hierarchy [Domain]
Fair Value Hierarchy [Domain]
Level 1 [Member]
Fair Value, Inputs, Level 1 [Member]
Level 2 [Member]
Fair Value, Inputs, Level 2 [Member]
Level 3 [Member]
Fair Value, Inputs, Level 3 [Member]
Measurement Basis [Axis]
Measurement Basis [Axis]
Fair Value Measurement [Domain]
Fair Value Measurement [Domain]
Portion at Fair Value Measurement [Member]
Portion at Fair Value Measurement [Member]
Other [Member]
Portion at Other than Fair Value Measurement [Member]
Low [Member]
High [Member]
Weighted Average [Member]
Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis
Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure [Abstract]
Cash and Cash Equivalents
Cash and Cash Equivalents, Fair Value Disclosure
Risk Management Assets
Derivative Asset [Abstract]
Risk Management Assets
Derivative Asset
Spent Nuclear Fuel and Decommissioning Trusts
Nuclear Fuel and Decommissioning Trusts [Abstract]
Nuclear Fuel and Decommissioning Trusts Abstract.
Total Assets
Assets, Fair Value Disclosure
Liabilities, Fair Value Disclosure [Abstract]
Liabilities, Fair Value Disclosure [Abstract]
Risk Management Liabilities
Derivative Liability
Changes in the Fair Value of Net Trading Derivatives and Other Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)
Settlements
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, (Sales), Issuances, (Settlements)
Transfers into Level 3
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3
Transfers out of Level 3
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3
Changes in Fair Value Allocated to Regulated Jurisdiction
Changes in Fair Value Allocated to Regulated Jurisdiction
This element represents total gains or losses for the period (realized and unrealized), arising from assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are allocated to regulated jurisdictions.
Ending Balance
Level 3 Quantitative Information [Abstract]
Fair Value Inputs, Quantitative Information [Abstract]
Forward Price Range Low
Low Market Price
Low market price for unobservable inputs.
Forward Price Range High
High Market Price
High market price for unobservable inputs.
Weighted Average Market Price
Weighted Average Market Price
Weighted average market price for unobservable inputs.
Counterparty Credit Risk
Fair Value Inputs, Counterparty Credit Risk
Fair Value Measurements 1 (Textuals) [Abstract]
Fair Value Measurements 1 (Textuals) [Abstract]
Fair value measurements textuals abstract for assets and liabilities measured on a recurring basis.
Maturity Of Net Fair Value Of Risk Management Contracts Prior To Cash Collateral Assets Or Liabilities
Maturity Of Net Fair Value Of Risk Management Contracts Prior To Cash Collateral Assets Or Liabilities
Maturity of the net fair value of risk management contracts prior to cash collateral, assets or liabilities.
Derivatives and Hedging
Derivatives, Policy [Policy Text Block]
Statement of Stockholders' Equity [Abstract]
Common Stock [Member]
Common Stock [Member]
Additional Paid-in Capital [Member]
Additional Paid-in Capital [Member]
Noncontrolling Interests [Member]
Noncontrolling Interest [Member]
Common Stock, Dividends, Per Share, Declared
Common Stock, Dividends, Per Share, Declared
Beginning Balance
Beginning Balance, Shares
Issuance of Common Stock, Value
Stock Issued During Period, Value, New Issues
Issuance of Common Stock, Shares
Stock Issued During Period, Shares, New Issues
Capital Contributions from Parent
Proceeds from Contributions from Parent
Common Stock Dividends
Dividends, Common Stock
Common Stock Dividends
Affiliated Dividends Common Stock
Equity impact of aggregate cash, stock, and paid-in-kind dividends declared to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.
Common Stock Dividends
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders
Stockholders' Equity, Other
Stockholders' Equity, Other
Net Income (Loss)
Net Income (Loss) Attributable to Parent
Other Comprehensive Income (Loss)
Contribution of Amos Plant from Parent
NoncashContributionsFromParent
Noncash Contribution of Amos Plant from Parent.
Contribution of Mutual Energy SWEPCo, LLC from Parent
Contribution of Mutual Energy SWEPCo, LLC from Parent
Contribution of Mutual Energy SWEPCo, LLC from Parent.
Ending Balance
Ending Balance, Shares
Statement of Cash Flows [Abstract]
Operating Activites
Net Cash Provided by (Used in) Operating Activities [Abstract]
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Deferred Income Taxes
Amortization (Deferral) of Incremental Nuclear Refueling Outage Expenses, Net
Deferral of Incremental Nuclear Refueling Outage Expenses, Net
The net cash inflow or outflow due to Cook Unit 1 & 2 refueling outage levelization.
Asset Impairments and Other Related Charges
Carrying Costs Income
Allowance for Equity Funds Used During Construction
Mark-to-Market of Risk Management Contracts
Unrealized Gain (Loss) on Derivatives
Amortization of Nuclear Fuel
Amortization of Nuclear Fuel
The expense charged against earnings for the periodic recognition of nuclear fuel usage.
Pension and Postemployment Benefit Reserves
Pension and Other Postretirement Benefit Expense
Pension Contributions to Qualified Plan Trust
Pension Contributions
Property Taxes
Amortization of Deferred Property Taxes
Deferred Fuel Over/Under-Recovery, Net
Fuel Over Under Recovery Net
The net change during the reporting period in the value of the asset (liability) created by an (over) under recovery of fuel costs. An over recovery represents the excess of fuel revenues billed to customers over fuel costs incurred and an under recovery represents excess fuel costs incurred over fuel revenues billed to customers.
Provision for Refund
Provision for Refund
Provision for Refund
Change in Regulatory Liabilities
Change in Regulatory Liabilities
The increase (decrease) during the reporting period in regulatory liabilities.
Purchased Electricity Over Under Recovery Net
Purchased Electricity Over Under Recovery Net
Purchased Electricity Over/Under Recovery, Net
Deferral of Ohio Capacity Costs, Net
Deferral Of Ohio Capacity Costs
The increase (decrease) during the reporting period in amounts for the net under recovery of capacity deferrals related to the differential between $189/MW-day capacity cost and RPM (reliability pricing model) pricing.
Provision for Refund - Global Settlement
Provision for Refund - Global Settlement
Provisions for refund for obligations to customers as a result of the OPCo Global Settlement.
Disposition of Tanners Creek Plant Site
Disposition of Tanners Creek Plant Site
Cash outflow relating to the disposition of Tanners Creek plant site, and associated ARO, to a third party.
Change in Regulatory Assets
Change in Regulatory Assets
The increase (decrease) during the reporting period in regulatory assets.
Change in Other Noncurrent Assets
Increase (Decrease) in Other Noncurrent Assets
Change in Other Noncurrent Liabilities
Increase (Decrease) in Other Noncurrent Liabilities
Changes in Certain Components of Working Capital:
Increase (Decrease) in Operating Capital [Abstract]
Accounts Receivable, Net
Increase (Decrease) in Accounts and Other Receivables
Fuel, Materials and Supplies
Increase (Decrease) in Inventories
Accounts Payable
Increase (Decrease) in Accounts Payable
Accrued Taxes, Net
Increase (Decrease) in Accrued Taxes Payable
Other Current Assets
Increase (Decrease) in Other Current Assets
Other Current Liabilities
Increase (Decrease) in Other Current Liabilities
Net Cash Flows from (Used for) Operating Activities
Net Cash Provided by (Used in) Operating Activities
Investing Activities
Net Cash Provided by (Used in) Investing Activities [Abstract]
Construction Expenditures
Payments for Construction in Process
Change in Restricted Cash for Securitized Funding
Increase (Decrease) in Restricted Cash
Change in Other Temporary Investments, Net
Change In Other Temporary Investments Net
Change in investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.
Change in Advances to Affiliates, Net
Increase (Decrease) in Notes Receivable, Related Parties
Purchases of Investment Securities
Payments to Acquire Investments
Sales of Investment Securities
Proceeds from Sale, Maturity and Collection of Investments
Acquisitions of Nuclear Fuel
Payments for Nuclear Fuel
Acquisitions of Assets
Payments to Acquire Property, Plant, and Equipment
Proceeds from Notes Receivable - Affiliated
ProceedsFromNotesReceivableAffiliated
The cash inflow from the redemption of affiliated debt.
Other Investing Activities
Payments for (Proceeds from) Other Investing Activities
Net Cash Flows from (Used for) Investing Activities
Net Cash Provided by (Used in) Investing Activities
Financing Activities
Net Cash Provided by (Used in) Financing Activities [Abstract]
Issuance of Common Stock, Net
Proceeds from Issuance of Common Stock
Change in Advances from Affiliates, Net
Increase (Decrease) in Notes Payable, Related Parties
Change in Short-term Debt, Net
Proceeds from (Repayments of) Short-term Debt, Maturing in Three Months or Less
Retirement of Long-term Debt
Retirement of Long-term Debt - Affiliated
Repayments of Related Party Debt
Make Whole Premium on Extinguishment of Long-term Debt
Make Whole Premium on Extinguishment of Long-term Debt
The cash outflow for a make whole premium on long-term debt extinguished early.
Principal Payments for Capital Lease Obligations
Repayments of Long-term Capital Lease Obligations
Dividends Paid on Common Stock
Payments of Distributions to Affiliates
Dividends Paid on Common Stock
Payments of Ordinary Dividends, Common Stock
Other Financing Activities
Proceeds from (Payments for) Other Financing Activities
Net Cash Flows from (Used for) Financing Activities
Net Cash Provided by (Used in) Financing Activities
Cash Provided by (Used in) Operating Activities, Discontinued Operations
Cash Provided by (Used in) Operating Activities, Discontinued Operations
Cash Provided by (Used in) Investing Activities, Discontinued Operations
Cash Provided by (Used in) Investing Activities, Discontinued Operations
Cash Provided by (Used in) Financing Activities, Discontinued Operations
Cash Provided by (Used in) Financing Activities, Discontinued Operations
Net Increase (Decrease) 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 End of Period
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts
Net Cash Paid (Received) for Income Taxes
Noncash Acquisitions Under Capital Leases
Noncash Contribution of Amos Plant from Parent
Noncash Contribution of Mutual Energy SWEPCo, LLC from Parent
Noncash Increase in Advances to Affiliates, Net due to Contribution of Mutual Energy SWEPCo, LLC
Noncash or Part Noncash Acquisition, Investments Acquired
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]
Securitization Bonds [Member]
Securitization Bonds [Member]
A collateralized debt obligation (backed by pledge, mortgage or other lien on the entity's assets).
Senior Unsecured Notes [Member]
Senior Unsecured Notes [Member]
A senior note is a bond that takes priority over other debt securities sold by the issuer, in the event the issuer goes bankrupt, senior debt holders receive priority for [must receive] repayment [prior] relative to junior and unsecured [general] creditors.
Notes Payable [Member]
Notes Payable, Other Payables [Member]
AEP Texas Central Co [Member]
AEP Texas Central Co [Member]
AEP Texas Central Company Member
Non-Registrant AEP Subsidiaries [Member]
Non-Registrant AEP Subsidiaries [Member]
Non-Registrant AEP Subsidiaries [Member]
Short-term Debt, Type [Axis]
Short-term Debt, Type [Axis]
Short-term Debt, Type [Domain]
Short-term Debt, Type [Domain]
Commercial Paper [Member]
Commercial Paper [Member]
Money Pool Participant by Company Type [Axis]
Money Pool Participant by Company Type [Axis]
Money Pool Participant by Company Type.
Money Pool Participant by Company Type [Domain]
Money Pool Participant by Company Type [Domain]
Money Pool Participant by Company Type.
Utility [Member]
Utility [Member]
Utility Company.
Nonutility [Member]
Nonutility [Member]
Nonutility Company.
Shares of Company
Shares of Company [Abstract]
Shares of Company.
Issued
Treasury Stock, Shares, Beginning Balance
Treasury Stock, Shares, Ending Balance
Long-term Debt
Long-term Debt, Unclassified [Abstract]
Senior Unsecured Notes
Unsecured Debt
Pollution Control Bonds
Long-term Pollution Control Bond
Notes Payable
Other Notes Payable
Spent Nuclear Fuel Obligation
Other Long-term Debt
Other Long-term Debt
Long- term Debt by Type of Debt and Maturity
Long term Debt by Type of Debt and Maturity [Abstract]
Long term Debt by Type of Debt and Maturity.
Maturity Date Low
Debt Instrument Maturity Date Range Low
Earliest date the outstanding debt instruments are required to be repaid.
Maturity Date High
Debt Instrument Maturity Date Range High
Earliest date the outstanding debt instruments are required to be repaid.
Weighted Average Interest Rate
Long-term Debt, Weighted Average Interest Rate
Interest Rate
Debt Instrument, Interest Rate, Effective Percentage
Outstanding Long-term Debt
Long-term Debt, Fiscal Year Maturity [Abstract]
Principal Amount, 2017
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months
Principal Amount, 2018
Long-term Debt, Maturities, Repayments of Principal in Year Two
Principal Amount, 2019
Long-term Debt, Maturities, Repayments of Principal in Year Three
Principal Amount, 2020
Long-term Debt, Maturities, Repayments of Principal in Year Four
Principal Amount, 2021
Long-term Debt, Maturities, Repayments of Principal in Year Five
Principal Amount, After 2021
Long-term Debt, Maturities, Repayments of Principal after Year Five
Principal Amount, Total
Long-term Debt, Gross
Unamortized Discount, Net and Debt Issuance Costs
Unamortized Discount, Net And Debt Issuance Costs
The amount of debt discount and issuance costs (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.
Short-term Debt
Short term Debt [Abstract]
Short-term Debt.
Securitized Debt for Receivables
Commercial Paper
Commercial Paper
Securitized Debt for Receivables
Short-term Debt, Weighted Average Interest Rate
Commercial Paper
Debt, Weighted Average Interest Rate
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits [Abstract]
Money Pool Participants Money Pool Activity And Authorized Borrowing Limits [Abstract]
Maximum Borrowings from Money Pool
Maximum Borrowings from Money Pool
Maximum Borrowings from a Money Pool at anytime during the period. The Money Pool represents a centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.
Maximum Loans to Money Pool
Maximum Loans to Money Pool
Maximum Loans to a Money Pool at anytime during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.
Average Borrowings from Money Pool
Average Borrowings from Money Pool
Average Borrowings from a Money Pool during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.
Average Loans to Money Pool
Average Loans to Money Pool
Average Loans to a Money Pool during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.
Net Loans (Borrowings) to/from Money Pool
Related Party Transaction, Due from (to) Related Party, Current
Authorized Short Term Borrowing Limit
Authorized Short Term Borrowing Limit
Authorized Short-term Borrowing Limit by regulatory orders.
Maximum and Minimum Interest Rates
Maximum and Minimum Interest Rates [Abstract]
Maximum and Minimum Interest Rates.
Maximum Interest Rate
Maximum Interest Rate
The maximum weighted-average interest rate of funds outstanding at that time, calculated on a daily basis, either borrowed from or loaned to a Money Pool during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.
Minimum Interest Rate
Minimum Interest Rate
The minimum weighted-average interest rate of funds outstanding at that time, calculated on a daily basis, either borrowed from or loaned to a Money Pool during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool [Abstract]
Average Interest Rates for Funds Borrowed From and Loaned to Money Pool.
Average Interest Rate For Funds Borrowed
Average Interest Rate For Funds Borrowed
The average interest rate for funds borrowed from a Money Pool during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.
Average Interest Rate For Funds Loaned
Average Interest Rate For Funds Loaned
The average interest rate for funds loaned to a Money Pool during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.
Interest Expense
Interest Expense [Abstract]
Interest Expense Incurred on Borrowings from the Money Pool
Interest Expense, Related Party
Interest Income
Interest and Other Income [Abstract]
Interest Income Earned On Advances To Money Pool
Interest Income Earned On Advances To Money Pool
Interest income earned on advances to the Money Pool. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.
Comparative Accounts Receivable Information
Comparative accounts receivable information [Abstract]
Comparative accounts receivable information.
Effective Interest Rates on Securitization of Accounts Receivable
Effective Interest Rates on Securitization of Accounts Receivable
Effective interest rate on the amount owed for securitized accounts receivables.
Net Uncollectible Accounts Receivable Written Off
Net Uncollectible Accounts Receivable Written Off
Net uncollectible accounts receivable written off.
Customer Accounts Receivable Managed Portfolio
Customer Accounts Receivable Managed Portfolio [Abstract]
Customer accounts receivable managed portfolio.
Accounts Receivable Retained Interest and Pledged as Collateral Less Uncollectible Accounts
Accounts Receivable Retained Interest and Pledged as Collateral Less Uncollectible Accounts
Accounts receivables that have been pledged as collateral less uncollectible accounts as of the balance sheet date.
Total Principal Outstanding
Principal Amount Outstanding on Loans Held-for-sale or Securitization or Asset-backed Financing Arrangement
Delinquent Securitized Accounts Receivable
Delinquent Amount at End of Period on Loans Managed and Securitized or Asset-backed Financing Arrangement
Bad Debt Reserves Related to Securitized Sale of Accounts Receivable
Bad Debt Reserves Related to Securitized Sale of Accounts Receivable
A valuation allowance for securitized receivables that are expected to be uncollectible.
Unbilled Receivables Related to Securitization, Sale of Accounts Receivable
Unbilled Receivables Related to Securitization, Sale of Accounts Receivable
The amount of revenue for work performed for which billing has not occurred related to securitization of accounts receivable.
Accounts Receivable and Accrued Unbilled Revenue
Accounts Receivable and Accrued Unbilled Revenue [Abstract]
Accounts Receivable and Accrued Unbilled Revenues
Receivables Held-for-sale, Amount
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Fees Paid to AEP Credit for Customer Accounts Receivable Sold [Abstract]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Distribution and Servicing Fees
Proceeds on Sale of Receivables to AEP Credit
Proceeds on Sale of Receivables to AEP Credit [Abstract]
Proceeds from Sale of Receivables to AEP Credit
Proceeds from Sale of Finance Receivables
Financing Activities (Textuals) [Abstract]
Financing Activities Textuals [Abstract]
Financing Activities.
Debt Instrument, Interest Rate, Stated Percentage
Debt Instrument, Interest Rate, Stated Percentage
Total Commitment From Bank Conduits To Finance Receivables
Total Commitment From Bank Conduits To Finance Receivables
Total commitment from bank conduits to finance receivables.
Reaquired Pollution Control Bonds Held by Trustees
Auction Rate Tax Exempt Long Term Debt Outstanding
Securities that are debt instruments (corporate or municipal bonds) that typically have long-term nominal maturities for which the interest rate is reset through an auction process.
Maximum Percentage Debt to Capitalization
Maximum Percentage Debt to Capitalization
Maximum level of debt to capitalization persuant to credit agreement leverage restrictions.
Restricted Net Assets
Restricted Net Assets
A segregation of retained earnings which is unavailable for dividend distribution.
Retained Earnings Available to Pay Dividends
Retained Earnings, Unappropriated
Dividend Restrictions
Dividend Payment Restrictions
Amount of restricted net assets of subsidiaries that may not be distributed to Parent in the form of a loan, advance or dividend.
Credit Facilities, Total
Maximum Amount of Commercial Paper Outstanding
Short-term Debt, Maximum Amount Outstanding During Period
Weighted Average Interest Rate of Commercial Paper Outstanding During Year
Debt Instrument, Interest Rate During Period
Due Date
Debt Instrument, Maturity Date 1
Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).
Performance Units and Reinvested Dividends on Outstanding Performance Units
Performance units and reinvested dividends on outstanding performance units [Text Block]
Tabular disclosure of the number and weighted-average grant date fair value for performance units and career shares that were outstanding at the beginning and end of the year and the vesting period.
Summary of Performance Scores and Performance Units Earned
Summary Of Performance Scores And Performance Units Earned [Text Block]
Tabular disclosure of performance scores and performance units earned, deferred and paid.
Summary of Cash Payouts for Performance Units and Career Shares
Summary Of Cash Payouts For Performance Units And Career Shares [Text Block]
Tabular disclosure of cash payouts for performance units and career shares.
Summary of Units Awarded and Fair Value of Restricted Stock Units
Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]
Total Fair Value and Total Intrinsic Value of Restricted Shares and Restricted Stock Units Vested
Total fair value and total intrinsic value of restricted shares and restricted stock units vested [Text Block]
Tabular disclosure of the total intrinsic value of restricted shares and restricted stock units vested, and the total fair value of restricted shares and restricted stock units vested during the year.
Status of Nonvested Restricted Shares and Restricted Stock Units
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]
Stock Unit Accumulation Plan for Non-employee Directors
Schedule of Share-based Compensation, Nonemployee Director Stock Award Plan, Activity [Table Text Block]
Compensation Cost and Actual Tax Benefit Realized for Tax Deductions from Compensation Cost for Share-based Payment Arrangements
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]
Schedule of Quarterly Financial Information
Quarterly Financial Information [Table Text Block]
Contractual Commitments
Recorded Unconditional Purchase Obligations [Table Text Block]
Maximum Future Payments for Letters of Credit Uncommitted Facilities
Maximum Future Payments for Letters of Credit Uncommitted Facilities [Table Text Block]
[Table Text Block] for aep_MaximumFuturePaymentsForLettersOfCreditUncommittedFacilitiesTextBlock [Table]
Pollution Control Bonds Supported by Bilateral Letters of Credit
Pollution Control Bonds Supported by Bilateral Letters of Credit [Text Block]
Pollution control bonds supported by bilateral letters of credit.
Variable Interest Entities
Consolidation, Variable Interest Entity, Policy [Policy Text Block]
Basis of Accounting
Basis of Accounting [Text Block]
Rates and Service Regulation
Regulated Jurisdictions [Policy Text Block]
Identifies the regulatory jurisdictions in which the entity operates and the primary regulator.
Principles of Consolidation
Consolidation, Policy [Policy Text Block]
Accounting for the Effects of Cost-Based Regulation
Regulatory Assets and Liabilities Recognition Criteria [Policy Text Block]
Describes the entity's criteria for recording regulatory assets and regulatory liabilities only because they are included in the rate-setting process, and rate-related accruals and deferrals, such as amounts receivable from (or due to) customers under fuel adjustment clauses and interim rates collected prior to regulatory approval.
Use of Estimates
Use of Estimates, Policy [Policy Text Block]
Cash and Cash Equivalents
Cash and Cash Equivalents, Policy [Policy Text Block]
Other Temporary Investments
Other Temporary Investments Policy [Text Block]
Policy for Other Temporary Investments
Restricted Cash for Securitized Funding
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]
Inventory
Inventory, Policy [Policy Text Block]
Accounts Receivable
Receivables, Policy [Policy Text Block]
Allowance for Uncollectible Accounts
Allowance for Uncollectible Accounts Policy [Text Block]
Describes how an entity determines the level of its allowance for doubtful accounts for its trade and other accounts receivable balances, and when impairments, charge-offs or recoveries are recognized. The description identifies the factors that influence management's establishment of the level of the allowance (for example, historical losses and existing economic conditions) and may also include discussion of the risk elements relevant to particular categories of receivables.
Concentrations of Credit Risk and Significant Customers
Concentration Risk, Credit Risk, Policy [Policy Text Block]
Emission Allowances
Emission Credits or Allowances, Policy [Policy Text Block]
Property, Plant and Equipment and Equity Investments
Property, Plant and Equipment, Policy [Policy Text Block]
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization
Allowance for Funds Used During Construction, Policy [Policy Text Block]
Fair Value Measurements of Assets and Liabilities
Fair Value of Financial Instruments, Policy [Policy Text Block]
Deferred Fuel Costs
Capitalization and Amortization of Fuel Costs, Policy [Policy Text Block]
Revenue Recognition
Revenue Recognition, Policy [Policy Text Block]
Levelization of Nuclear Refueling Outage Costs
Levelization Of Nuclear Refueling Outage Costs [Text Block]
Policy for deferring incremental operating and maintenance costs during a refueling for amortization over the fuel burn cycle.
Maintenance
Maintenance Cost, Policy [Policy Text Block]
Income Taxes and Investment Tax Credits
Excise Taxes
Excise Tax Policy [Text Block]
Describes an entity's accounting policy for excise taxes.
Debt
Debt, Policy [Policy Text Block]
Goodwill and Intangible Assets, Policy
Goodwill and Intangible Assets, Policy [Policy Text Block]
Investments Held in Trust for Future Liabilities
Defined Benefit Plan Investment Policies And Strategies Narrative Description [Text Block]
A narrative description of investment policies and strategies, including target allocation percentages or range of percentages considering the major categories of plan assets as of the latest statement of financial position presented (on a weighted-average basis for employers with more than one plan), and other factors that are pertinent to an understanding of those policies and strategies such as investment goals, risk management practices, allowable and prohibited investment types including the use of derivatives, diversification, and the relationship between plan assets and benefit obligations. For investment funds disclosed as major categories, the narrative description shall include a description of the significant investment strategies of those funds.
Nuclear Trust Funds
Trust Assets For Decommissioning And Spent Nuclear Fuel Disposal (Policy) [Text Block]
Element used to describe policy for trust assets for decommissioning and spent nuclear fuel disposal.
Comprehensive Income (Loss)
Comprehensive Income, Policy [Policy Text Block]
Earnings Per Share
Earnings Per Share, Policy [Policy Text Block]
Fair Value Measurements
Fair Value Disclosures [Text Block]
Fair Values of Long-term Debt
Book Values And Fair Values Of Long Term Debt Policy [Text Block]
Policy for determining fair value of long-term debt.
Fair Value Assets And Liabilities Measured On Recurring Basis
Fair Value Assets And Liabilities Measured On Recurring Basis (Policy) [Text Block]
Element describes policy for fair value assets and liabilities measured on recurring basis.
Goodwill and Intangible Assets Disclosure [Text Block]
Goodwill and Intangible Assets Disclosure [Text Block]
Transmission and Distribution Companies [Member]
Transmission And Distribution Companies [Member]
Transmission And Distribution Companies [Member]
AEP Transmission Holdco
Transmission Operations [Member]
Transmission Operations Member.
All Other [Member]
Other Segments [Member]
Consolidation Items [Axis]
Consolidation Items [Axis]
Consolidation Items [Domain]
Consolidation Items [Domain]
Consolidation Eliminations [Member]
Consolidation, Eliminations [Member]
Segment Reconciling Items [Member]
Segment Reconciling Items [Member]
Reportable Segment Information
Segment Reporting Information, Profit (Loss) [Abstract]
Sales Revenue, Net
Revenue, Net
Revenues
Income from Continuing Operations
Gross Property Additions
Property, Plant and Equipment, Additions
Balance Sheet Information
Segment Reporting Information, Additional Information [Abstract]
Total Property, Plant and Equipment
Assets Held for Sale
Disposal Group, Including Discontinued Operation, Assets
Total Assets
Investments in Equity Method Investees
Equity Method Investments
Total Long-term Debt Outstanding
Liabilities Held for Sale
Disposal Group, Including Discontinued Operation, Liabilities
Document and Entity Information [Abstract]
Document And Entity Information.
Entities [Table]
Entities [Table]
Entity Registrant Name
Entity Registrant Name
Entity Central Index Key
Entity Central Index Key
Document Type
Document Type
Document Period End Date
Document Period End Date
Amendment Flag
Amendment Flag
Document Fiscal Year Focus
Document Fiscal Year Focus
Document Fiscal Period Focus
Document Fiscal Period Focus
Current Fiscal Year End Date
Current Fiscal Year End Date
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 Filer Category
Entity Filer Category
Entity Public Float
Entity Public Float
Entity Common Stock, Shares Outstanding
Entity Common Stock, Shares Outstanding
Vertically Integrated Utilities Revenues [Member]
Vertically Integrated Utilities Revenues [Member]
Vertically Integrated Utilities Revenues.
Transmission and Distribution Utilities Revenues [Member]
Transmission and Distribution Utilities Revenues [Member]
Transmission and Distribution Revenues.
Generation and Marketing Revenues [Member]
Generation and Marketing Revenues [Member]
Generation and Marketing Revenues.
Electric Generation, Transmission and Distribution Revenues [Member]
Electric Generation Transmission Distribution Revenues [Member]
Electric Generation, Transmission and Distribution Revenues.
Sales to AEP Affiliates [Member]
Sales to AEP Affiliates [Member]
Sales to AEP affiliates.
Purchased Electricity for Resale [Member]
Purchased Electricity for Resale [Member]
Purchased Electricity for Resale.
Other Operation Expense [Member]
Other Operation Expense [Member]
Other operation expense.
Maintenance Expense [Member]
Maintenance Expense [Member]
Maintenance expense.
Regulatory Liabilities [Member]
Regulatory Liabilities [Member]
Regulatory Liabilities.
Interest Rate and Foreign Currency [Member]
Gross Amounts of Risk Management Assets/Liabilities Recognized [Member]
Gross Amounts of Risk Management Assets Liabilities Recognized [Member]
Gross Amounts of Risk Management Assets/Liabilities Recognized.
Gross Amounts Offset in the Statement of Financial Position [Member]
Gross Amounts Offset in Statement of Financial Position [Member]
Gross Amounts Offset in the Statement of Financial Position.
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member]
Net Amounts of Assets Liabilities Presented in Statement of Financial Position [Member]
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position.
Power [Member]
Power Contract Member [Member]
Nominal energy measure used to calculate payments on a derivative instrument.
Coal [Member]
Coal Contract [Member]
Natural Gas [Member]
Natural Gas Contract Member [Member]
Nominal energy measure used to calculate payments on a derivative instrument.
Heating Oil and Gasoline [Member]
Heating Oil And Gasoline Contract Member [Member]
Nominal volume used to calculate payments on a derivative instrument.
Interest Rate Contract [Member]
Interest Rate Contract [Member]
Risk Management Contracts [Member]
Hedging Contracts [Member]
Hedging Contracts [Member]
Notional Volume Of Derivative Instruments
Notional Volume Of Derivative Instruments [Abstract]
Notional Volume Of Derivative Instruments Abstract.
Derivative, Energy Notional Amount
Derivative Nonmonetary Energy Notional Amount
Volume of power derivatives contracts.
Derivative, Mass Notional Amount
Derivative Nonmonetary Mass Notional Amount
Volume of coal derivative contracts.
Derivative, Volume Notional Amount
Derivative Nonmonetary Volume Notional Amount
Volume of heating oil and gasoline derivative contracts.
Derivative, Notional Amount
Derivative, Notional Amount
Cash Collateral Netting
Cash Collateral Netting [Abstract]
Cash collateral netting detail.
Cash Collateral Received Netted Against Risk Management Assets
Securities Received as Collateral
Cash Collateral Paid Netted Against Risk Management Liabilities
Obligation to Return Securities Received as Collateral
Fair Value of Derivative Instruments
Derivative Instrument Detail [Abstract]
Current Risk Management Assets
Total Assets
Current Risk Management Liabilities
Long-term Risk Management Liabilities
Total Liabilities
Total MTM Derivative Contract Net Assets (Liabilities)
Derivative Assets (Liabilities), at Fair Value, Net
Amount of Gain (Loss) Recognized on Risk Management Contracts
Gain (Loss) on Derivative Instruments, Net, Pretax [Abstract]
Amount of Gain (Loss) Recognized on Risk Management Contracts
Gain (Loss) on Derivative Instruments, Net, Pretax
Amount of Gain (Loss) Recognized on Risk Management Contracts
Derivative Risk Management Contracts Gain Loss Recognized As Regulatory Asset Liability
Realized and unrealized gains and losses subject to regulatory accounting treatment recorded as either current or noncurrent on the balance sheets.
Gain (Loss) on Hedging Instruments
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Gain (Loss) on Fair Value Hedging Instruments
Derivative, Gain (Loss) on Derivative, Net
Gain (Loss) on Fair Value Portion of Long-term Debt
Gain (Loss) on Fair Value Portion of Long Term Debt
Gain (Loss) on fair value portion of long-term debt.
Impact of Cash Flow Hedges on the Balance Sheet
Impact of Cash Flow Hedges on our Consolidated Balance Sheet [Abstract]
Impact of Cash Flow Hedges on our Consolidated Balance Sheet.
Hedging Assets
Hedging Assets
Impact of cash flow hedges on balance sheet hedging assets.
Hedging Liabilities
Hedging Liabilities
Impact of cash flow hedges on balance sheet hedging liabilities.
AOCI Gain (Loss) Net of Tax
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax
Portion Expected to be Reclassified to Net Income During the Next Twelve Months
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months
Collateral Triggering Events [Abstract]
Collateral Triggering Events [Abstract]
Collateral Triggering Events Abstract.
Amount of Collateral the Registrants Would Have Been Required to Post Attributable to RTOs and ISOs
Amount Attributable To RTO and ISO Activities
Aggregate fair value of derivative contracts that would be required to be posted if credit rating had dropped below investment grade that are attributable to Regional Transmission Organizations and Independant System Operators.
Amount of Collateral Attributable to Other Contracts
Amount Attributable to Other Contracts
The aggregate fair value of other significant contracts that would be required to be posted if credit rating had dropped below investment grade.
Liabilities for Contracts with Cross Default Provisions Prior to Contractural Netting Arrangements
Fair Value Of Derivative Liabilities Subject To Cross Default Provisions
Fair value of derivative liabilities subject to cross-default provisions.
Amount of Cash Collateral Posted
Collateral Already Posted, Aggregate Fair Value
Additional Settlement Liability if Cross Default Provision is Triggered
Assets Needed for Immediate Settlement, Aggregate Fair Value
Derivatives and Hedging (Textuals) [Abstract]
Derivatives and Hedging Textuals [Abstract]
Derivatives and Hedging Textuals
Maximum Length of Time Hedged in Price Risk Cash Flow Hedge
Maximum Length of Time Hedged in Price Risk Cash Flow Hedge
Cross Default Provisions Maximum Third Party Obligation Amount
Cross Default Provisions Maximum Third Party Obligation Amount
Non-exchange traded commodity contracts containing cross-default provisions
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Pronouncements
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]
Regulatory Assets
Schedule of Regulatory Assets [Table Text Block]
Regulatory Liabilities
Schedule of Regulatory Liabilities [Table Text Block]
Reduction In ARO Liability [Axis]
Reduction In ARO Liability [Axis]
Reduction In ARO Liability [Axis]
Reduction In ARO Liability [Domain]
Reduction In ARO Liability [Domain]
[Domain] for Reduction In ARO Liability [Axis]
Reduction in ARO Liability due to the execution of a joint use agreement with a third party [Member]
Reduction in ARO Liability due to the execution of a joint use agreement with a third party [Member]
Reduction in ARO Liability due to the execution of a joint use agreement with a third party.
Muskingum River Plant [Member]
Muskingum River Plant [Member]
Muskingum River Plant [Member]
Transmission [Member]
Transmission [Member]
Transmission Member
Conesville Generating Station (Unit No. 4) [Member]
Conesville Generating Station (Unit No. 4) [Member]
Conesville Generating Station (Unit No. 4) Member
J.M. Stuart Generating Station [Member]
Jm Stuart Generating Station [Member]
J.M. Stuart Generating Station member
Wm. H. Zimmer Generating Station [Member]
Wm. H. Zimmer Generating Station [Member]
Wm. H. Zimmer Generating Station Member
Dolet Hills Generating Station (Unit No. 1) [Member]
Dolet Hills Generating Station (Unit No. 1) [Member]
Dolet Hills Generating Station (Unit No. 1) Member
Flint Creek Generating Station (Unit No. 1) [Member]
Flint Creek Generating Station (Unit No. 1) [Member]
Flint Creek Generating Station (Unit No. 1) Member
Pirkey Generating Station (Unit No. 1) [Member]
Pirkey Generating Station (Unit No. 1) [Member]
Pirkey Generating Station (Unit No. 1) Member
Oklaunion Generating Station (Unit No. 1) [Member]
Oklaunion Generating Station (Unit No. 1) [Member]
Oklaunion Generating Station (Unit No. 1) Member
Turk Generating Plant [Member]
Turk Generating Plant [Member]
Turk Generating Plant Member
Jointly Owned Electricity Transmission and Distribution System [Member]
Jointly Owned Electricity Transmission and Distribution System [Member]
AEP Texas North Co [Member]
AEP Texas North Co [Member]
AEP Texas North Company Member
Functional Class of Property [Axis]
Functional Class of Property [Axis]
Functional Class of Property - including Generation, Transmission, Distribution and Other
Functional Class of Property [Domain]
Functional Class of Property [Domain]
Functional Class of Property
Generation [Member]
Generation [Member]
Generation Member
Distribution [Member]
Distribution [Member]
Distribution Member
Other Property Class [Member]
Other Property Class [Member]
Other Property Class
Inventory [Axis]
Inventory [Axis]
Inventory [Domain]
Inventory [Domain]
Coal [Member]
Coal [Member]
Public Utilities, Inventory, Lignite [Member]
Public Utilities, Inventory, Lignite [Member]
A soft brownish coal between bituminous coal and peat, which is extracted from the ground and used as fuel.
Depreciation, Depletion and Amortization
Depreciation, Depletion And Amortization [Abstract]
Depreciation, Depletion and Amortization.
Property, Plant and Equipment, Generation
Property, Plant and Equipment, Transmission
Property, Plant and Equipment, Distribution
Property, Plant and Equipment, Other
Property, Plant and Equipment, Construction Work in Progress
Accumulated Depreciation
Annual Composite Depreciation Rate
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service
Depreciable Life Ranges - Generation
Public Utilities, Property, Plant and Equipment, Generation, Useful Life
Public Utilities, Property, Plant and Equipment, Transmission, Useful Life
Public Utilities, Property, Plant and Equipment, Transmission, Useful Life
Public Utilities, Property, Plant and Equipment, Distribution, Useful Life
Public Utilities, Property, Plant and Equipment, Distribution, Useful Life
Public Utilities, Property, Plant and Equipment, Other Property Plant and Equipment, Useful Life
Public Utilities, Property, Plant and Equipment, Other Property Plant and Equipment, Useful Life
Asset Retirement Obligations (ARO)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning Balance
Asset Retirement Obligation
Accretion Expense
Asset Retirement Obligation, Accretion Expense
Liabilities Incurred
Asset Retirement Obligation, Liabilities Incurred
Liabilities Settled
Asset Retirement Obligation, Liabilities Settled
Revisions in Cash Flow Estimates
Asset Retirement Obligation, Revision of Estimate
Ending Balance
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization
Public Utilities, Allowance for Funds Used During Construction, Net Increase [Abstract]
Allowance for Borrowed Funds Used During Construction
Allowance for Funds Used During Construction, Capitalized Interest
Jointly-owned Electric Facilities
Jointly Owned Electric Facilities [Abstract]
Jointly-owned Electric Facilities.
Percent of Ownership
Utility Plant in Service
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service
Construction Work in Progress
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress
Accumulated Depreciation
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation
Property, Plant and Equipment (Textuals) [Abstract]
Property, Plant and Equipment (Textuals) [Abstract]
Property Plant And Equipment Textuals Abstract.
Property, Plant and Equipment -Assets Held for Sale
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment
Asset Retirement Obligations (ARO) Liability for Nuclear Decommissioning of the Cook Plant
Decommissioning Liability, Noncurrent
Fair Value of Legally Restricted Assets
Asset Retirement Obligation, Legally Restricted Assets, Fair Value
Tanners Creek Plant, Units 1-4 [Member]
Noncurrent Regulatory Assets [Axis]
Noncurrent Regulatory Assets [Axis]
Noncurrent Regulatory Assets Axis
Regulatory Assets [Domain]
Regulatory Assets [Domain]
Regulatory Assets Domain
Deferred Capacity Costs [Member]
Deferred Capacity Costs [Member]
Deferred capacity costs.
FERC Transmission Complaint [Member]
FERC Transmission Complaint [Member]
FERC Transmission Complaint [Member]
Indiana Amended PJM Settlement Agreement [Member]
Indiana Amended PJM Settlement Agreement [Member]
Indiana Amended PJM Settlement Agreement [Member]
Kingsport Base Rate Case [Member]
Kingsport 2015 Base Rate Case [Member]
Kingsport 2015 Base Rate Case [Member]
Ohio Electric Security Plan Filing [Member]
Ohio Electric Security Plan Filing [Member]
Ohio Electric Security Plan Filing
Ohio Fuel Adjustment Clause Audit - 2009 [Member]
Ohio Fuel Adjustment Clause Audit - 2009 [Member]
2009 Ohio Fuel Adjustment Clause Audit
Ohio Global Settlement [Member]
Ohio Global Settlement [Member]
Ohio Global Settlement [Member]
Rockport Plant, Unit 2 Selective Catalytic Reduction [Member]
Rockport Plant, Unit 2 Selective Catalytic Reduction [Member]
Rockport Plant, Unit 2 Selective Catalytic Reduction [Member]
Special Rate Mechanism For Ormet [Member]
Special Rate Mechanism For Ormet [Member]
Special rate mechanism for Ormet.
West Virginia Deferred Base Rate Increase [Member]
West Virginia Deferred Base Rate Increase [Member]
West Virginia Deferred Base Rate Increase [Member]
West Virginia Expanded Net Energy Charge - 2016 [Member]
West Virginia Expanded Net Energy Charge [Member]
West Virginia Expanded Net Energy Charge [Member]
Additional ENEC Revenues Per Settlement Agreement
Additional ENEC Revenues Per Settlement Agreement
Amount of additional ENEC revenues approved in settlement agreement.
Construction Surcharge Revenues Per Settlement Agreement
Construction Surcharge Revenues Per Settlement Agreement
Amount of construction surcharge revenues included in settlement agreement.
Amount of Annual Delayed Customer Billing to Residential Customers
Amount Of Annual Delayed Customer Billing To Residential Customers
Amount of annual delayed customer billing to residential customers.
Amount of Recovery Approved Related to Delayed Billing Including Carrying Charges
Amount of Recovery Approved Related to Delayed Billing Including Carrying Charges
Amount of recovery approved related to delayed billing, including carrying charges.
Recovery Percentage of Certain Transmission Expense Though the Indiana PJM Rider Approved Through 2017
Recovery Percentage of Certain Transmission Expense Though the Indiana PJM Rider Approved Through 2017
Previously approved percentage of recovery of certain transmission expenses through the Indiana PJM Rider through 2017.
Approved Recovery Percentage of Certain Transmission Expense through the Indiana PJM Rider from January 2017 Through June 2018
Approved Recovery Percentage of Certain Transmission Expense through the Indiana PJM Rider from January 2017 Through June 2018
Approved percentage of recovery, subject to a cap, of certain transmission expenses through the Indiana PJM rider from January 2017 through June 2018.
Approved Cap on Amounts Recovered Through the Indiana PJM Rider from January 2017 Through June 2018
Approved Cap on Amounts Recovered Through the Indiana PJM Rider from January 2017 Through June 2018
Approved cap on amounts recovered through the Indiana PJM rider from January 2017 through June 2018.
Approved Recovery Percentage of Certain Transmission Expense Through the Indiana PJM Rider from July 2018 Until IURC Addresses in Subsequent Proceeding
Approved Recovery Percentage of Certain Transmission Expense Through the Indiana PJM Rider from July 2018 Until IURC Addresses in Subsequent Proceeding
Approved recovery percentage of certain transmission expense through the Indiana PJM rider from July 218 until the IURC addresses in a subsequent proceeding.
Approved Base Rate Increase
Approved Base Rate Increase
Approved base rate increase.
Approved Return on Common Equity
Approved Return On Equity
Approved return on equity.
Proposed Reduction in PIRR Rate Collected from Customers
Proposed Reduction in PIRR Rate Collected from Customers
Proposed reduction in the PIRR rate to be collected from customers.
Proposed Total RSR Revenues to be Collected Through June 2019
Proposed Total RSR Revenues to be Collected Through June 2019
Total proposed RSR revenues to be collected, subject to true up, through June 2019.
Proposed RSR Collection Period (in months)
Proposed RSR Collection Period (in months)
Proposed collection period of RSR revenues (in months).
Increase in RSR Capacity Costs Recorded in December 2016 Resulting from Global Settlement
Increase in RSR Capacity Costs Recorded in December 2016 Resulting from Global Settlement
Increase in RSR capacity costs recorded in December 2016 resulting from Ohio Global Settlement.
Increase in RSR Capacity Costs Related Carrying Charges Recorded in December 2016 Resulting from Global Settlement
Increase in RSR Capacity Costs Related Carrying Charges Recorded in December 2016 Resulting from Global Settlement
Increase in RSR capacity costs-related carrying charges recorded in December 2016 resulting from Ohio Global Settlement.
Fuel and Other Consumables Used for Electric Generation
Purchased Electricity for Resale
Total Decrease in RSR Expense Recorded in December 2016 Resulting from Global Settlement
Total Decrease in RSR Expense Recorded in December 2016 Resulting from Global Settlement
Total decrease in RSR expense recorded in December 2016.
Proposed Refund to Customers Associated with Remands Related to SEET
Proposed Refund to Customers Associated with Remands Related to SEET
Proposed refund to customers, per Global Settlment Agreement, associated with remands related to SEET proceedings.
Proposed Refund Period (in months)
Proposed Refund Period (in months)
Proposed refund period (in months).
Amount Accrued in December 2016 Related to Proposed Customer Refunds
Amount Accrued in December 2016 Related to Proposed Customer Refunds
Amount accrued in December 2016 related to proposed customer refunds.
Proposed Refund to SSO Customers Related to OVEC and Lawrenceburg Purchases
Proposed Refund to SSO Customers Related to OVEC and Lawrenceburg Purchases
Proposed refund to SSO customers related to OVEC and Lawrenceburg Purchases.
Amount Accrued in December 2016 Related to Proposed SSO Customer Refunds
Amount Accrued in December 2016 Related to Proposed SSO Customer Refunds
Amount accrued in December 2016 related to proposed SSO customer refunds.
Proposed Increase in PIRR Rates
Proposed Increase in PIRR Rates
Amount of increase in PIRR rates requested in filing.
Amount of Recovery Requested for Under-Recovered Fuel Costs
Amount of Recovery Requested for Under-Recovered Fuel Costs
Amount of recovered requested related to under-recovered fuel costs.
PUCO-ordered Fixed Price per MW Day for Customers Who Switch During ESP Period
PUCO-Ordered Fixed Price For Customers Who Switch During ESP Period
PUCO-ordered fixed price per MW day for customers who switch during the electric security plan period.
Reliability Pricing Model Rate per MW Day in Effect through May 2014
Reliability Pricing Model Rate In Effect Through May 2014
Reliability pricing model rate per MW day in effect through May 2014.
Reliability Pricing Model Rate per MW Day in Effect from June 2014 through May 2015
Reliability Pricing Model Rate per MW Day in Effect from June 2014 Through May 2015
Reliability pricing model rate per MW day in effect from June 2014 through May 2015.
Energy Credit Offset Applied Against the Capacity Deferral Threshold (per MW day)
Energy Credit Offset Applied Against the Capacity Deferral Threshold (per MW day)
Energy Credit Offset Applied Against the Capacity Deferral Threshold (per MW day)
Overstatement of Energy Credit Used in the Determination of the Capacity Deferral Threshold (per MW day)
Overstatement of Energy Credit Used in the Determination of the Capacity Deferral Threshold (per MW day)
Overstatement of Energy Credit Used in the Determination of the Capacity Deferral Threshold (per MW day)
Retail Stability Rider through May 2014 ($ Per MWh)
Retail Stability Rider For Period June 2012 Through May 2014
Amount per MWh to be collected from customers under the Retail Stability Rider through May 2014.
Retail Stability Rider for the Period June 2014 through May 2015 ($ per MWh)
Retail Stability Rider For Period June 2014 Through May 2015
Amount per MWh to be collected from customers under the Retail Stability Rider for the period June 2014 through May 2015.
Amount of Retail Stability Rider Applied to the Deferred Capacity Costs ($ per MWh)
Retail Stability Rider Amount Applied To Deferred Capacity Costs
Amount per MWh of Retail Stability Rider collected that will be applied to the deferred capacity costs balance for the period June 2014 through May 2015.
Retail Stability Rider Rate to be Continued Until Capacity Deferral Balance is Collected as Ordered by the PUCO ($ per MWh)
Retail Stability Rider Rate to be Continued Until Capacity Deferral Balance is Collected as Ordered by the PUCO ($ per MWh)
The retail stability rider rate to be continued until the capacity deferral balance is collected, as ordered by the PUCO ($ per MWh).
Deferred Capacity Costs Recovery Period as Ordered by PUCO (in months)
Deferred Capacity Costs Recovery Period as Ordered by PUCO (in months)
Deferred Capacity Costs Recovery Period as Ordered by PUCO (in months)
Annual Retail Share of Fixed Fuel Costs
Annual Retail Share of Fixed Fuel Costs
Annual retail share of fixed fuel costs for the period August 2012 through May 2015.
Requested Net Increase in Deferred Capacity Costs
Requested Net Increase in Deferred Capacity Costs
Requested net increase in deferred capacity costs.
Amount of Decrease in Capacity Costs Related to Non-Deferral Portion of RSR Collections
Amount of Decrease in Capacity Costs Related to Non-Deferral Portion of RSR Collections
Amount of decrease in capacity costs related to the non-deferral portion of the RSR collections.
Amount of Increase in Capacity Costs Related to the Correction of the Energy Credit
Amount of Increase in Capacity Costs Related to the Correction of the Energy Credit
Amount of increase in capacity costs related to the correction of the energy credit.
Approved Return on Common Equity
Public Utilities, Approved Return on Equity, Percentage
Amount of Potential Customer Credits to be Included in the PPA Rider Over the Final Four Years as Proposed in Stipulation Agreement
Amount Of Potential Customer Credits To Be Included In PPA Rider Over Final Four Years As Proposed In Stipulation Agreement
Amount of potential additional contingent customer credits to be included in the PPA Rider over the final four years, as proposed in the stipulation agreement.
Solar Energy Projects to be Developed and Implemented by 2021 as Proposed in Stipulation Agreement (in MWs)
Solar Energy Projects To Be Developed And Implemented By 2021 As Proposed In Stipulation Agreement
Solar energy projects to be developed and implemented by 2021 as proposed in stipulation agreement (in MWs).
Wind Energy Projects to be Developed and Implemented by 2021 as Proposed in Stipulation Agreement (in MWs)
Wind Energy Projects To Be Developed And Implemented By 2021 As Proposed In Stipulation Agreement
Wind energy projects to be developed and implemented by 2021 as proposed in stipulation agreement (in MWs).
Percentage of Output to be Received from Solar and Wind Projects as Proposed in Stipulation Agreement
Percentage of Output to be Received from Solar and Wind Projects as Proposed in Stipulation Agreement
Percentage of output to be received from solar and wind projects as proposed in stipulation agreement.
Maximum Ownership Percentage of Solar and Wind Projects as Proposed in Stipulation Agreement
Maximum Ownership Percentage of Solar and Wind Projects as Proposed in Stipulation Agreement
Maximum ownership percentage of solar and wind projects as proposed in stipulation agreement.
Temporary Customer-Specific Rate Impact Cap Through May 2018
Temporary Customer-Specific Rate Impact Cap Through May 2018
Temporay customer-specific rate impact cap through May 2018 as included in PUCO order.
PUCO Approved Reduced Customer Credits
PUCO Approved Reduced Customer Credits
PUCO-approved amount of reduced customer credits.
Return on Common Equity Proposed in the Amended ESP Filing
Return on Common Equity Proposed in the Amended ESP Filing
The return on common equity proposed in the amended ESP filing.
Future Commitment to Support the Development of a Large Solar Farm
Future Commitment To Support Development Of Large Solar Farm
Future commitment to support the development of a large solar farm.
Gridsmart Investment as Proposed in Stipulation Agreement
Gridsmart Investment as Proposed in Stipulation Agreement
Amount of gridSMART investment over a six-year period, as proposed in stipulation agreement.
Significantly Excessive Earnings Test Threshold Previously Established for Ohio Power
Significantly Excessive Earnings Test Threshold Previously Established for Ohio Power
Significantly Excessive Earnings Test Threshold Previously Established for Ohio Power
Significantly Excessive Earnings Test Threshold Remanded Back to the PUCO
Significantly Excessive Earnings Test Threshold Remanded Back to the PUCO
Significantly Excessive Earnings Test Threshold Remanded Back to the PUCO
Intervenor Recommended Revenue Refund Related to 2014 SEET
Intervenor Recommended Revenue Refund Related to 2014 SEET
Intervenor recommended revenue refund related to 2014 SEET.
2008 Coal Contract Settlement Proceeds to be Applied to Deferred Fuel Balance as Originally Ordered by the PUCO
Coal Contract Settlement Proceeds to be Applied to Deferred Fuel Balance
2008 coal contract settlement proceeds to be applied to deferred fuel balance as originally ordered by the PUCO.
Net Favorable Fuel Adjustment Recorded in 2012 Based on Fuel Adjustment Clause Audit Rehearing
Net Favorable Fuel Adjustment Recorded In 2012 Based On Fuel Adjustment Clause Audit Rehearing
Net favorable fuel adjustment recorded in 2012 based upon a 2009 fuel adjustment clause audit rehearing.
Deferred Fuel Adjustment Clause Related to Ormet Interim Arrangement as of September 2009
Deferred Fuel Adjustment Clause Related to Ormet Interim Arrangement as of September 2009
Amount in the deferred fuel adjustment clause related to the Ormet interim arrangement including recognized carrying charges as of September 2009.
Unrecognized Equity Carrying Costs Related to Ormet Interim Arrangement as of September 2009
Unrecognized Equity Carrying Costs Related to Ormet Interim Arrangement as of September 2009
Unrecognized equity carrying costs related to the Ormet interim arrangement as of September 2009.
Percentage of Deferred Fuel Adjustment Clause Costs Attributable to Columbus Southern Power
Percentage of Deferred Fuel Adjustment Clause Costs Attributable to Columbus Southern Power
Percentage of deferred FAC costs related to CSPCo.
Percentage of Deferred Fuel Adjustment Clause Costs Attributable to Ohio Power
Percentage of Deferred Fuel Adjustment Clause Costs Attributable to Ohio Power
Percentage of deferred FAC costs related to OPCo.
Intervenor Recommended Return on Common Equity
Intervenor Recommended Return On Common Equity Range
Intervenor recommended return on common equity.
Impaired Long-Lived Assets Held and Used by Type [Axis]
Impaired Long-Lived Assets Held and Used by Type [Axis]
Impaired Long-Lived Assets Held and Used, Asset Name [Domain]
Impaired Long-Lived Assets Held and Used, Asset Name [Domain]
I&M Price River Coal Reserves [Member]
I&M Price River Coal Reserves [Member]
I&M Price River Coal Reserves [Member]
Merchant Coal-Fired Generation Assets [Member]
Merchant Coal-Fired Generation Assets [Member]
Merchant Coal-Fired Generation Assets [Member]
Trent and Desert Sky Wind Farms [Member]
Trent and Desert Sky Wind Farms [Member]
Trent and Desert Sky Wind Farms [Member]
Coal Reserves [Member]
Coal Reserves [Member]
Coal Reserves [Member]
Total Impaired Assets [Member]
Total Impaired Assets [Member]
Total Impaired Assets [Member]
Dispositions, Assets and Liabilities Held for Sale and Impairments (Textuals) [Abstract]
Dispositions, Assets and Liabilities Held for Sale and Impairments (Textuals) [Abstract]
Dispositions, Assets and Liabilities Held for Sale and Impairments (Textuals) [Abstract]
Payment on Sale of the Plant
Payment On Sale Of Property Plant And Equipment
The cash outflow associated with the sale of plant including the payment for pollution legal liability, with Seller as the sole insured in the event Purchaser does not meet its obligaitons with respect to assumed liabilities.
Gain on Sale of Muskingum River Plant
Gain (Loss) on Disposition of Assets
Cash Proceeds from Sale of Disposition Plants, Net
Cash Proceeds from Disposition of Business, Net
Cash Proceeds from Disposition of Business, Net
Pretax Income (Loss) of Disposal Group
IncomeLossFromDisposalGroupClassifiedAssetsAndLiabilitiesHeldForSaleBeforeIncomeTax
Amount before tax of income (loss) from a disposal group classified as assets and liabilities held for sale.
Make Whole Premium on Extinguishment of Long-term Debt
Disposal Group, Balance Sheet Disclosure [Abstract]
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Fuel
Disposal Group, Including Discontinued Operation, Inventory
Materials and Supplies
DisposalGroupIncludeingDiscontinuedOperationMaterialsAndSupplies
Amount classified as materials and supplies attributable to disposal group held for sale or disposed of.
Property, Plant and Equipment - Net
Other Classes of Assets That Are Not Major
Disposal Group, Including Discontinued Operation, Other Assets
Total Assets from Discontinued Operations on the Balance Sheet
Long-term Debt
Disposal Group, Including Discontinued Operation, Long-term Debt
Amount classified as long-term debt attributable to disposal group held for sale or disposed of.
Waterford Plant Upgrade Liability
DisposalGroupIncludingDiscontinuedOperationWaterfordPlantUpgradeLiability
Amount classified as Waterford Plant Upgrade Liability attributable to disposal group held for sale or disposed of.
Asset Retirement Obligations
DisposalGroupIncludingDiscontinuedOperationAssetRetirementObligation
Amount classified as asset retirement obligation attributable to disposal group held for sale or disposed of.
Other Classes of Liabilities That Are Not Major
Disposal Group, Including Discontinued Operation, Other Liabilities
Total Liabilities from Discontinued Operations on the Balance Sheet
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Other Revenues
Disposal Group, Including Discontinued Operation, Revenue
Other Operation Expense
Disposal Group, Including Discontinued Operation, Other Operation Expense
Amount of other operation expense attributable to disposal group, including, but not limited to, discontinued operation.
Maintenance Expense
Disposal Group, Including Discontinued Operation, Maintenance Expense
Amount of maintenance expense attributable to disposal group, including, but not limited to, discontinued operation.
Depreciation and Amortization Expense
Disposal Group, Including Discontinued Operation, Depreciation and Amortization
Taxes Other Than Income Taxes
Disposal Group Including Discontinued Operation, Taxes Other Than Income Tax
Amount of tax other than income tax expense attributable to disposal group, including, but not limited to, discontinued operation.
Total Expenses
Disposal Group, Including Discontinued Operation, Expense
Amount of expense attributable to disposal group, including, but not limited to, discontinued operation.
Other Expense
Disposal Group, Including Discontinued Operation, Other Expense
Pretax Income of Discontinued Operations
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax
Income Tax Expense
Equity Earnings of Unconsolidated Subsidiaries
Disposal Group Including Discontinued Operation Income (Loss) From Equity Method Investment
Amount of income (loss) from equity method investment attributable to disposal group, including, but not limited to, discontinued operation.
Income from Discontinued Operations of AEPRO
Income (Loss) From Discontinued Operations Not Including Gain (Loss) From Disposal Of Discontinued Operation, Net of Tax
Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Not includes gain (loss) on disposal.
Gain on Sale of Discontinued Operations
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax
Income Tax Expense (Benefit)
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation
Gain on Sale of Discontinued Operations, Net of Tax
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax
Total Income on Discontinued Operations as Presented on the Statements of Income
Asset Impairment Charges [Abstract]
Asset Impairment Charges [Abstract]
Property, Plant, and Equipment, Fair Value Disclosure
Property, Plant, and Equipment, Fair Value Disclosure
Public Utilities, Property, Plant and Equipment, Net
Options [Member]
Equity Option [Member]
Real Estate Investment Trusts [Member]
Real Estate Investment [Member]
Common Collective Trusts [Member]
Common Collective Trust [Member]
Common Collective Trust [Member]
Common Collective Trust - Debt [Member]
Common Collective Trust Debt [Member]
Common Collective Trust - Debt [Member]
United States Government and Agency Securities [Member]
US Treasury and Government [Member]
Corporate Debt [Member]
Foreign Debt [Member]
Foreign Debt [Member]
Foreign Debt [Member]
State and Local Government [Member]
US States and Political Subdivisions Debt Securities [Member]
Other - Asset Backed [Member]
Asset-backed Securities [Member]
Infrastructure [Member]
Infrastructure [Member]
Infrastructure.
Real Estate [Member]
Real Estate [Member]
Alternative Investments [Member]
Alternative Investments [Member]
Alternative Investments.
Securities Lending [Member]
Securities Lending [Member]
Securities Lending.
Securities Lending Collateral [Member]
Securities Pledged as Collateral [Member]
Trusted Owned Life Insurance [Member]
Trusted Owned Life Insurance [Member]
Trusted Owned Life Insurance Member
International Equities [Member]
International Equities [Member]
International Equities [Member]
United States Bonds [Member]
US Treasury Bond Securities [Member]
Other - Pending Transactions and Accrued Income [Member]
Other Pending Transactions and Accrued Income [Member]
Other Pending Transactions and Accrued Income.
Level 2 [Member]
Pension Plan [Member]
Allocated Assets of Investments
Allocated Assets of Investments
Percentage of investments that are allocated to the Registrant Subsidiary.
Pension and Other Postretirement Plans' Assets
Defined Benefit Plan, Information about Plan Assets [Abstract]
Asset Class
Year End Allocation
Pension and Other Postretirement Plans Assets Percentage [Abstract]
Pension and Other Postretirement Plans' Assets Percentage.
Total
Defined Benefit Plan, Actual Plan Asset Allocations
Reconciliation of Changes in Fair Value of Assets Classified as Level 3 in Fair Value Hierarchy for the Pension Assets
Reconciliation Of Changes In Fair Value Of Level 3 Plan Assets [Abstract]
Reconciliation of changes in fair value of assets classified as Level 3 in fair value hierarchy for the pension assets.
Balance as of January 1
Actual Return on Plan Assets
Defined Benefit Plan, Actual Return on Plan Assets [Abstract]
Relating to Assets Still Held as of the Reporting Date
Defined Benefit Plan, Actual Return on Plan Assets Still Held
Relating to Assets Sold During the Period
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period
Purchases and Sales
Defined Benefit Plan, Purchases, Sales, and Settlements
Balance as of December 31