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Rate Matters (Details) (USD $)
3 Months Ended9 Months Ended
Sep. 30, 2011
Sep. 30, 2010
Sep. 30, 2011
Sep. 30, 2010
Dec. 31, 2010
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent$ 5,731,000,000 $ 5,731,000,000 $ 4,943,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent5,731,000,000 5,731,000,000 4,943,000,000
Write off of Sporn Five, Pretax90,000,000090,000,0000 
Regulatory Liabilities, Noncurrent3,229,000,000 3,229,000,000 3,171,000,000
Construction in Progress, Gross3,105,000,000 3,105,000,000 2,758,000,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners26,000,00017,000,00069,000,00060,000,000 
Amounts Recorded Related to Capacity Auction True-Up  421,000,000  
EXTRAORDINARY ITEM, NET OF TAX273,000,0000273,000,0000 
Carrying Costs Income291,000,00018,000,000323,000,00051,000,000 
Columbus Southern Power Co [Member] | Ohio Electric Security Plan Filings [Member]
     
Rate Matters (Textuals) [Abstract]     
Refund of Provider of Last Resort Charges, Pretax  34,000,000  
Amount Exceeded the Return on Equity Threshold  2.13%  
Excessive Earnings Refund Ordered by the PUCO  43,000,000  
Intervenors Recommended Refund of Excessive Earnings  41,000,000  
Commission Staff's Recommended Refund of Excessive Earnings  21,000,000  
Columbus Southern Power Co [Member] | Ohio Electric Security Plan Filings [Member] | Rate Matters Year One [Member]
     
Rate Matters (Textuals) [Abstract]     
Limit to Increase in Rates Issued in the ESP Order  7.00%  
Columbus Southern Power Co [Member] | Ohio Electric Security Plan Filings [Member] | Rate Matters Year Two [Member]
     
Rate Matters (Textuals) [Abstract]     
Limit to Increase in Rates Issued in the ESP Order  6.00%  
Columbus Southern Power Co [Member] | Ohio Electric Security Plan Filings [Member] | Rate Matters Year Three [Member]
     
Rate Matters (Textuals) [Abstract]     
Limit to Increase in Rates Issued in the ESP Order  6.00%  
Ohio Power Co [Member] | Ohio Electric Security Plan Filings [Member]
     
Rate Matters (Textuals) [Abstract]     
Refund of Provider of Last Resort Charges, Pretax  9,000,000  
Ohio Power Co [Member] | Ohio Electric Security Plan Filings [Member] | Rate Matters Year One [Member]
     
Rate Matters (Textuals) [Abstract]     
Limit to Increase in Rates Issued in the ESP Order  8.00%  
Ohio Power Co [Member] | Ohio Electric Security Plan Filings [Member] | Rate Matters Year Two [Member]
     
Rate Matters (Textuals) [Abstract]     
Limit to Increase in Rates Issued in the ESP Order  7.00%  
Ohio Power Co [Member] | Ohio Electric Security Plan Filings [Member] | Rate Matters Year Three [Member]
     
Rate Matters (Textuals) [Abstract]     
Limit to Increase in Rates Issued in the ESP Order  8.00%  
Ohio Power Co [Member] | Ohio Electric Security Plan Filings [Member] | Ohio Fuel Adjustment Clause Deferrals [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent542,000,000 542,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent542,000,000 542,000,000  
Unrecognized Equity Carrying Costs40,000,000 40,000,000  
Ohio Electric Security Plan Filings [Member] | January 2012 Through December 2012 [Member] | Columbus Southern Power Co, Ohio Power Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Requested Increase in Customer Rates  1.40%  
Percentage of Generation Capacity Offered to Competitive Retail Suppliers  21.00%  
Ohio Electric Security Plan Filings [Member] | January 2013 Through December 2013 [Member] | Columbus Southern Power Co, Ohio Power Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Requested Increase in Customer Rates  2.70%  
Ohio Electric Security Plan Filings [Member] | January 2013 Through December 2013 [Member] | Columbus Southern Power Co, Ohio Power Co [Member] | Minimum [Member]
     
Rate Matters (Textuals) [Abstract]     
Percentage of Generation Capacity Offered to Competitive Retail Suppliers  29.00%  
Ohio Electric Security Plan Filings [Member] | January 2013 Through December 2013 [Member] | Columbus Southern Power Co, Ohio Power Co [Member] | Maximum [Member]
     
Rate Matters (Textuals) [Abstract]     
Percentage of Generation Capacity Offered to Competitive Retail Suppliers  31.00%  
Ohio Electric Security Plan Filings [Member] | January 2014 - May 2015 [Member] | Columbus Southern Power Co, Ohio Power Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Percentage of Generation Capacity Offered to Competitive Retail Suppliers  41.00%  
Columbus Southern Power Co [Member] | Ohio Distribution Base Rate Case [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent102,000,000 102,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent102,000,000 102,000,000  
Unrecognized Equity Carrying Costs64,000,000 64,000,000  
Requested Base Rate Increase  34,000,000  
Requested Recovery of Projected Distribution Regulatory Assets  216,000,000  
Projected Unrecognized Equity Carrying Costs  102,000,000  
Columbus Southern Power Co [Member] | Ohio Distribution Base Rate Case [Member] | Minimum [Member]
     
Rate Matters (Textuals) [Abstract]     
Rate Reduction Proposed By Commission Staff  2,000,000  
Columbus Southern Power Co [Member] | Ohio Distribution Base Rate Case [Member] | Maximum [Member]
     
Rate Matters (Textuals) [Abstract]     
Rate Reduction Proposed By Commission Staff  10,000,000  
Ohio Power Co [Member] | Ohio Distribution Base Rate Case [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent66,000,000 66,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent66,000,000 66,000,000  
Unrecognized Equity Carrying Costs48,000,000 48,000,000  
Requested Base Rate Increase  60,000,000  
Requested Recovery of Projected Distribution Regulatory Assets  159,000,000  
Projected Unrecognized Equity Carrying Costs  84,000,000  
Ohio Power Co [Member] | Ohio Distribution Base Rate Case [Member] | Minimum [Member]
     
Rate Matters (Textuals) [Abstract]     
Rate Increase Proposed By Commission Staff  23,000,000  
Ohio Power Co [Member] | Ohio Distribution Base Rate Case [Member] | Maximum [Member]
     
Rate Matters (Textuals) [Abstract]     
Rate Increase Proposed By Commission Staff  32,000,000  
Ohio Distribution Base Rate Case [Member] | Columbus Southern Power Co, Ohio Power Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Requested Return on Equity  11.15%  
Ohio Distribution Base Rate Case [Member] | Columbus Southern Power Co, Ohio Power Co [Member] | Minimum [Member]
     
Rate Matters (Textuals) [Abstract]     
Return on Common Equity Proposed By Commission Staff  8.58%  
Ohio Distribution Base Rate Case [Member] | Columbus Southern Power Co, Ohio Power Co [Member] | Maximum [Member]
     
Rate Matters (Textuals) [Abstract]     
Return on Common Equity Proposed By Commission Staff  9.60%  
Ohio Power Co [Member] | Sporn Unit 5 [Member]
     
Rate Matters (Textuals) [Abstract]     
Write off of Sporn Five, Pretax  48,000,000  
Ohio Power Co [Member] | Fuel Adjustment Clause Audit - 2009 [Member]
     
Rate Matters (Textuals) [Abstract]     
Amount Outside Consultants Recommended to Review Related to Proceeds from Coal Contract Settlement Agreement  72,000,000  
Of the Total Proceeds from the Coal Contract Settlement Agreement Amount Recognized as a Reduction to Fuel Expense  58,000,000  
Of the Total Proceeds from the Coal Contract Settlement Agreement Amount that Reduced Fuel Expense in 2009 and 2010  14,000,000  
Ohio Power Co [Member] | Fuel Adjustment Clause Audit - 2010 [Member]
     
Rate Matters (Textuals) [Abstract]     
Potential Refund of Carrying Costs  12,000,000  
Potential Refund of Unrecognized Equity Carrying Costs  14,000,000  
Columbus Southern Power Co [Member] | Ormet Interim Arrangement [Member]
     
Rate Matters (Textuals) [Abstract]     
Deferred Fuel Adjustment Clause Related to Ormet Interim Arrangement as of September 200930,000,000 30,000,000  
Unrecognized Equity Carrying Costs Related to Ormet Interim Arrangement as of September 20091,000,000 1,000,000  
Ohio Power Co [Member] | Ormet Interim Arrangement [Member]
     
Rate Matters (Textuals) [Abstract]     
Deferred Fuel Adjustment Clause Related to Ormet Interim Arrangement as of September 200934,000,000 34,000,000  
Unrecognized Equity Carrying Costs Related to Ormet Interim Arrangement as of September 20091,000,000 1,000,000  
Columbus Southern Power Co [Member] | Ohio IGCC Plant [Member]
     
Rate Matters (Textuals) [Abstract]     
Collection of Authorized Pre Construction Costs  12,000,000  
Pre Construction Costs Incurred for the IGCC Plant  11,000,000  
Established Net Regulatory Liability Before Interest1,000,000 1,000,000  
Regulatory Liabilities, Noncurrent2,000,000 2,000,000  
Ohio Power Co [Member] | Ohio IGCC Plant [Member]
     
Rate Matters (Textuals) [Abstract]     
Collection of Authorized Pre Construction Costs  12,000,000  
Pre Construction Costs Incurred for the IGCC Plant  11,000,000  
Established Net Regulatory Liability Before Interest1,000,000 1,000,000  
Regulatory Liabilities, Noncurrent2,000,000 2,000,000  
Southwestern Electric Power Co [Member] | Turk Plant [Member]
     
Rate Matters (Textuals) [Abstract]     
Subsidiary's Ownership Percentage73.00% 73.00%  
Total Current Estimated Generation Costs  1,700,000,000  
Total Current Estimated Transmission Costs  129,000,000  
Subsidiary's Estimated Share of the Generation Costs  1,300,000,000  
Subsidiary's Estimated Share of the Transmission Costs  129,000,000  
Construction in Progress, Gross1,300,000,000 1,300,000,000  
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners  197,000,000  
Contractual Construction Commitments of Joint Owners and Subsidiary  163,000,000  
Transmission Contractual Construction Commitments of Subsidiary  13,000,000  
Subsidiary's Share of the Contractual Construction Commitments  123,000,000  
Estimated Cancellation Fee Which Shall be Incurred by Joint Owners and Subsidiary If the Plant is Cancelled  101,000,000  
Transmission Cancellation Fees Which Shall be Incurred by Subsidiary If the Plant is Cancelled  1,000,000  
Subsidiary's Share of Cancellation Fees Which Shall be Incurred if the Plant is Cancelled  74,000,000  
The PUCT Required Cap on the Plant, Excluding AFUDC and Related Transmission Costs  1,522,000,000  
The PUCT Required Cap on CO2 Emission Costs (per ton)  28  
Southwestern Electric Power Co [Member] | Turk Plant [Member] | Electric Transmission [Member]
     
Rate Matters (Textuals) [Abstract]     
Construction in Progress, Gross88,000,000 88,000,000  
Southwestern Electric Power Co [Member] | Texas Turk Plant Rate Plan [Member] | April 2012 - October 2012 [Member]
     
Rate Matters (Textuals) [Abstract]     
Percentage of Financing Costs to be Recovered  40.00%  
Southwestern Electric Power Co [Member] | Texas Turk Plant Rate Plan [Member] | November 2012 - December 2013 [Member]
     
Rate Matters (Textuals) [Abstract]     
Percentage of Financing Costs to be Recovered  100.00%  
Texas Restructuring Appeals [Member] | January 2002 - September 2011 [Member] | AEP Texas Central Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Carrying Costs Income  261,000,000  
Texas Restructuring Appeals [Member] | AEP Texas Central Co [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent682,000,000 682,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent682,000,000 682,000,000  
Net Recoverable Texas Stranded Generation Costs  2,500,000,000  
Refund of Other Texas Net True-up Regulatory Liabilities  375,000,000  
Amounts Recorded Related to Capacity Auction True-Up  421,000,000  
EXTRAORDINARY ITEM, NET OF TAX  273,000,000  
Texas Restructuring Appeals [Member] | AEP Texas Central Co [Member] | Minimum [Member]
     
Rate Matters (Textuals) [Abstract]     
Requested Carrying Costs Through March 2012  396,000,000  
Requested Debt Component of Carrying Costs Through March 2012  280,000,000  
Requested Carrying Costs  368,000,000  
Requested Debt Component of Carrying Costs  261,000,000  
Texas Restructuring Appeals [Member] | AEP Texas Central Co [Member] | Maximum [Member]
     
Rate Matters (Textuals) [Abstract]     
Requested Carrying Costs Through March 2012  756,000,000  
Requested Debt Component of Carrying Costs Through March 2012  444,000,000  
Requested Carrying Costs  692,000,000  
Requested Debt Component of Carrying Costs  410,000,000  
Deferred Investment Tax Credits and Excess Deferred Federal Income Taxes [Member] | AEP Texas Central Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Tax Benefits and Associated Carrying Costs Related to Subsidiary's Generation Assets  103,000,000  
Tax Benefit Which the PUCT Agreed to Allow Subsidiary to Defer Refunding to Ratepayers  103,000,000  
The Amount Management Estimates Interest Expense Would Have Been Had They Accrued Interest on the Tax Benefit  30,000,000  
Contingency to Pay Accumulated Deferred Investment Tax Credits  101,000,000  
Excess Earnings [Member] | AEP Texas Central Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Refund of Excess Earnings Including Interest  55,000,000  
Appalachian Power Co [Member] | Virginia Biennial Rate Case [Member]
     
Rate Matters (Textuals) [Abstract]     
Requested Base Rate Increase  126,000,000  
Requested Return on Equity  11.65%  
Rate Increase Proposed By Commission Staff  31,000,000  
Return on Common Equity Proposed By Commission Staff  10.83%  
Renewable Portfolio Standards Incentive Included in Return on Equity  0.50%  
Amount of Increase in Depreciation Expense Proposed to be Mitigated in Recovery Until Next Base Case Filing  51,000,000  
Requested Net Base Rate Increase  75,000,000  
Return on Common Equity Proposed By Attorney General  11.03%  
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Environmental Rate Adjustment Clause [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent73,000,000 73,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent73,000,000 73,000,000  
Unrecognized Equity Carrying Costs17,000,000 17,000,000  
Requested Recovery of Rate Adjustment Clause Costs77,000,000 77,000,000  
Recommended Cost Recovery By Hearing Examiner  65,000,000  
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Environmental Rate Adjustment Clause [Member] | Minimum [Member]
     
Rate Matters (Textuals) [Abstract]     
Recommended Cost Recovery By Commission Staff  37,000,000  
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Environmental Rate Adjustment Clause [Member] | Maximum [Member]
     
Rate Matters (Textuals) [Abstract]     
Recommended Cost Recovery By Commission Staff  42,000,000  
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Deferred Wind Power Costs [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent34,000,000 34,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent34,000,000 34,000,000  
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Renewable Energy Program Rate Adjustment Clause [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent40,000,000 40,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent40,000,000 40,000,000  
Requested Recovery of Rate Adjustment Clause Costs6,000,000 6,000,000  
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Renewable Energy Program Rate Adjustment Clause [Member] | Minimum [Member]
     
Rate Matters (Textuals) [Abstract]     
Recommended Cost Recovery By Commission Staff  1,000,000  
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Renewable Energy Program Rate Adjustment Clause [Member] | Maximum [Member]
     
Rate Matters (Textuals) [Abstract]     
Recommended Cost Recovery By Commission Staff  6,000,000  
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | New Generation Rate Adjustment Clause [Member]
     
Rate Matters (Textuals) [Abstract]     
Purchase Price of the Dresden Plant  302,000,000  
Recommended Cost Recovery Per Stipulation Agreement  27,000,000  
Appalachian Power Co [Member] | West Virginia Base Rate Case [Member]
     
Rate Matters (Textuals) [Abstract]     
Approved Deferral of Storm Expenses  18,000,000  
West Virginia Base Rate Case [Member] | Appalachian Power Co, Wheeling Power Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Requested Base Rate Increase  156,000,000  
Requested Return on Equity  11.75%  
Approved Base Rate Increase  51,000,000  
Approved Return on Equity  10.00%  
Approved Deferral of Cost Reduction Initiative Expenses  15,000,000  
Appalachian Power Co [Member] | Product Validation Facility [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent19,000,000 19,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent19,000,000 19,000,000  
Write-off of Regulatory Asset, Pretax  41,000,000  
Appalachian Power Co [Member] | Carbon Capture and Sequestration Project [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent4,000,000 4,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent4,000,000 4,000,000  
Columbus Southern Power Co [Member] | Carbon Capture and Sequestration Project [Member]
     
Rate Matters (Textuals) [Abstract]     
Write-off of Regulatory Asset, Pretax  2,000,000  
Indiana Michigan Power Co [Member] | Carbon Capture and Sequestration Project [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent2,000,000 2,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent2,000,000 2,000,000  
Ohio Power Co [Member] | Carbon Capture and Sequestration Project [Member]
     
Rate Matters (Textuals) [Abstract]     
Write-off of Regulatory Asset, Pretax  7,000,000  
Public Service Co Of Oklahoma [Member] | Carbon Capture and Sequestration Project [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent1,000,000 1,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent1,000,000 1,000,000  
Southwestern Electric Power Co [Member] | Carbon Capture and Sequestration Project [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent4,000,000 4,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent4,000,000 4,000,000  
Carbon Capture and Sequestration Project [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent12,000,000 12,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent12,000,000 12,000,000  
Maximum Amount of Department of Energy Funding  334,000,000  
Costs Incurred  34,000,000  
Department of Energy Eligible Funding Received  13,000,000  
Net Cost of Carbon Capture Project  21,000,000  
Carbon Capture and Sequestration Project [Member] | Kentucky Power Co [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent1,000,000 1,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent1,000,000 1,000,000  
Carbon Capture and Sequestration Project [Member] | Appalachian Power Co, Indiana Michigan Power Co, Kentucky Power Co, Public Service Co of Oklahoma, Southwestern Electric Power Co [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent12,000,000 12,000,000 0
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent12,000,000 12,000,000 0
Appalachian Power Co [Member] | APCo's Filing for IGCC Plant [Member] | Applicable to West Virginia Jurisdiction [Member]
     
Rate Matters (Textuals) [Abstract]     
Amount of Deferred Preconstruction IGCC Costs for Future Recovery9,000,000 9,000,000  
Appalachian Power Co [Member] | APCo's Filing for IGCC Plant [Member] | Applicable to FERC Jurisdiction [Member]
     
Rate Matters (Textuals) [Abstract]     
Amount of Deferred Preconstruction IGCC Costs for Future Recovery2,000,000 2,000,000  
Appalachian Power Co [Member] | APCo's Filing for IGCC Plant [Member] | Applicable to Virginia Jurisdiction [Member]
     
Rate Matters (Textuals) [Abstract]     
Amount of Deferred Preconstruction IGCC Costs for Future Recovery9,000,000 9,000,000  
Appalachian Power Co [Member] | Expanded Net Energy Charge [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent380,000,000 380,000,000  
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent380,000,000 380,000,000  
Unrecognized Equity Carrying Costs8,000,000 8,000,000  
Appalachian Power Co [Member] | Expanded Net Energy Charge [Member] | Rate Matters Year Three [Member]
     
Rate Matters (Textuals) [Abstract]     
Approved Fixed Annual Carrying Cost Rate  4.00%  
Expanded Net Energy Charge [Member] | Rate Matters Year One [Member] | Appalachian Power Co, Wheeling Power Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Annual Phase-in Increase  124,000,000  
Expanded Net Energy Charge [Member] | Rate Matters Year Two [Member] | Appalachian Power Co, Wheeling Power Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Annual Phase-in Increase  96,000,000  
Approved Increase of Construction Surcharges  10,000,000  
Expanded Net Energy Charge [Member] | Rate Matters Year Three [Member] | Appalachian Power Co, Wheeling Power Co [Member]
     
Rate Matters (Textuals) [Abstract]     
Annual Phase-in Increase  98,000,000  
Approved Increase of Construction Surcharges  8,000,000  
Approved Increase in Carrying Charges  8,000,000  
Expanded Net Energy Charge [Member] | Appalachian Power Co, Wheeling Power Co [Member]
     
Rate Matters (Textuals) [Abstract]     
The Overall Increase in Rates as Granted by an Order to be Phased-In Over Four Years355,000,000 355,000,000  
Public Service Co Of Oklahoma [Member] | Fuel and Purchased Power 2008 [Member]
     
Rate Matters (Textuals) [Abstract]     
Current Shareholder's Percentage of Off-System Sales Margins Sharing  25.00%  
The Intervenors' Proposed New Shareholder Percentage of Off-system Sales Margins Sharing  10.00%  
Indiana Michigan Power Co [Member] | Michigan Base Rate Case - 2011 [Member]
     
Rate Matters (Textuals) [Abstract]     
Requested Base Rate Increase  25,000,000  
Requested Return on Equity  11.15%  
Requested Increase in Depreciation Expense  6,000,000  
Indiana Michigan Power Co [Member] | Indiana Base Rate Case [Member]
     
Rate Matters (Textuals) [Abstract]     
Requested Base Rate Increase  149,000,000  
Requested Return on Equity  11.15%  
Requested Increase in Depreciation Expense  25,000,000  
Seams Elimination Cost Allocation [Member]
     
Rate Matters (Textuals) [Abstract]     
Recognized Gross Seams Elimination Cost Allocation Revenue  220,000,000  
Payment if Compliance Filing is Accepted  20,000,000  
Amount of Estimated Interest Included in Payment  5,000,000  
Potential Receipt of Payment if Compliance Filing is Accepted  10,000,000  
Amount of Estimated Interest Included in Potential Receipt of Payment  3,000,000  
Amount of FERC Approved Settlements Applicable to SECA Revenue  112,000,000  
Remaining Amount of Contested SECA Revenues  108,000,000  
AEP Texas Central Co [Member] | Capacity Auction True-Up [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent682,000,000 682,000,000 0
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent682,000,000 682,000,000 0
AEP Texas Central Co [Member] | Storm Related Costs [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent25,000,000 25,000,000 25,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent25,000,000 25,000,000 25,000,000
Appalachian Power Co [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent1,498,907,000 1,498,907,000 1,486,625,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent1,498,907,000 1,498,907,000 1,486,625,000
Regulatory Liabilities, Noncurrent571,718,000 571,718,000 562,381,000
Construction in Progress, Gross582,528,000 582,528,000 562,280,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners2,451,000436,0004,546,0001,727,000 
Carrying Costs Income7,579,0007,565,00017,560,00023,627,000 
Appalachian Power Co [Member] | Mountaineer Carbon Capture and Storage Product Validation Facility [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent19,000,000 19,000,000 60,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent19,000,000 19,000,000 60,000,000
Appalachian Power Co [Member] | Environmental Rate Adjustment Clause [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent73,000,000 73,000,000 56,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent73,000,000 73,000,000 56,000,000
Appalachian Power Co [Member] | Deferred Wind Power Costs [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent40,000,000 40,000,000 29,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent40,000,000 40,000,000 29,000,000
Appalachian Power Co [Member] | Special Rate Mechanism for Century Aluminum [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent13,000,000 13,000,000 13,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent13,000,000 13,000,000 13,000,000
Southwestern Electric Power Co [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent356,589,000 356,589,000 332,698,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent356,589,000 356,589,000 332,698,000
Regulatory Liabilities, Noncurrent426,210,000 426,210,000 393,673,000
Construction in Progress, Gross1,398,465,000 1,398,465,000 1,071,603,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners12,692,0008,651,00034,861,00036,630,000 
Ohio Power Co [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent1,033,130,000 1,033,130,000 934,011,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent1,033,130,000 1,033,130,000 934,011,000
Write off of Sporn Five, Pretax89,824,000089,824,0000 
Regulatory Liabilities, Noncurrent131,044,000 131,044,000 126,403,000
Construction in Progress, Gross157,769,000 157,769,000 153,110,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners841,000947,0002,234,0002,964,000 
Carrying Costs Income18,393,0006,324,00033,049,00016,879,000 
Columbus Southern Power Co [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent314,149,000 314,149,000 298,111,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent314,149,000 314,149,000 298,111,000
Regulatory Liabilities, Noncurrent171,936,000 171,936,000 163,888,000
Construction in Progress, Gross147,900,000 147,900,000 172,793,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners572,000267,0001,890,0001,502,000 
Carrying Costs Income3,193,0002,028,0009,115,0006,212,000 
Columbus Southern Power Co [Member] | Acquisition of Monongahela Power [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent9,000,000 9,000,000 8,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent9,000,000 9,000,000 8,000,000
Columbus Southern Power Co [Member] | Acquisition of Monongahela Power [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent4,000,000 4,000,000 4,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent4,000,000 4,000,000 4,000,000
Public Service Co Of Oklahoma [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent252,127,000 252,127,000 263,545,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent252,127,000 252,127,000 263,545,000
Regulatory Liabilities, Noncurrent337,480,000 337,480,000 336,961,000
Construction in Progress, Gross46,114,000 46,114,000 59,091,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners189,00021,000839,000387,000 
Carrying Costs Income810,000763,0003,333,0002,449,000 
Public Service Co Of Oklahoma [Member] | Storm Related Costs [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent0 0 17,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent0 0 17,000,000
Indiana Michigan Power Co [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent540,210,000 540,210,000 556,254,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent540,210,000 540,210,000 556,254,000
Regulatory Liabilities, Noncurrent806,397,000 806,397,000 852,197,000
Construction in Progress, Gross366,185,000 366,185,000 301,534,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners  11,790,00011,945,000 
Indiana Michigan Power Co [Member] | Litigation Settlement [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent11,000,000 11,000,000 0
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent11,000,000 11,000,000 0
Columbus Southern Power Co, Ohio Power Co [Member] | Customer Choice Deferrals [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent60,000,000 60,000,000 59,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent60,000,000 60,000,000 59,000,000
Columbus Southern Power Co, Ohio Power Co [Member] | Storm Related Costs [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent31,000,000 31,000,000 30,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent31,000,000 31,000,000 30,000,000
Columbus Southern Power Co, Ohio Power Co [Member] | Line Extension Carrying Costs [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent64,000,000 64,000,000 55,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent64,000,000 64,000,000 55,000,000
Columbus Southern Power Co, Ohio Power Co [Member] | Economic Development Rider [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent12,000,000 12,000,000 6,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent12,000,000 12,000,000 6,000,000
Appalachian Power Co Kingsport Power Co [Member] | Storm Related Costs [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent27,000,000 27,000,000 28,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent27,000,000 27,000,000 28,000,000
Other Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent1,000,000 1,000,000 1,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent1,000,000 1,000,000 1,000,000
Other Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Not Yet Being Recovered [Member] | Regulatory Assets Currently Not Earning Return [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent6,000,000 6,000,000 4,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent6,000,000 6,000,000 4,000,000
Regulatory Assets Not Yet Being Recovered [Member]
     
Regulatory Assets Not Being Recovered [Abstract]     
Regulatory Assets, Noncurrent1,089,000,000 1,089,000,000 395,000,000
Rate Matters (Textuals) [Abstract]     
Regulatory Assets, Noncurrent$ 1,089,000,000 $ 1,089,000,000 $ 395,000,000