Rate Matters (Details) (USD $)	3 Months Ended			6 Months Ended
	Jun. 30, 2011		Jun. 30, 2010	Jun. 30, 2011		Jun. 30, 2010	Dec. 31, 2010
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	$ 5,004,000,000			$ 5,004,000,000			$ 4,943,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	5,004,000,000			5,004,000,000			4,943,000,000
Regulatory Liabilities, Noncurrent	3,246,000,000			3,246,000,000			3,171,000,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners	23,000,000		19,000,000	43,000,000		43,000,000
Construction in Progress, Gross	2,714,000,000			2,714,000,000			2,758,000,000
Columbus Southern Power Co [Member] | Ohio Electric Security Plan Filings [Member]
Rate Matters (Textuals) [Abstract]
Rates Subject to Refund	14,000,000			14,000,000
Total Unfavorable Adjustments Proposed By Intervenors	370,000,000			370,000,000
Reduction to Regulatory Assets Proposed by Intervenors	298,000,000			298,000,000
Refunds and Rate Reductions Proposed by Intervenors	72,000,000			72,000,000
Amount Exceeded the Return on Equity Threshold				2.13%
Excessive Earnings Refund Ordered by the PUCO	43,000,000			43,000,000
Excessive Earnings Refund Ordered by the PUCO, Net of Tax	28,000,000			28,000,000
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%
Columbus Southern Power Co [Member] | Ohio Electric Security Plan Filings [Member] | Ohio Fuel Adjustment Clause Deferrals [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	27,000,000			27,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	27,000,000			27,000,000
Unrecognized Equity Carrying Costs	388,000			388,000
Ohio Power Co [Member] | Ohio Electric Security Plan Filings [Member]
Rate Matters (Textuals) [Abstract]
Rates Subject to Refund	16,000,000			16,000,000
Total Unfavorable Adjustments Proposed By Intervenors	417,000,000			417,000,000
Reduction to Regulatory Assets Proposed by Intervenors	336,000,000			336,000,000
Refunds and Rate Reductions Proposed by Intervenors	81,000,000			81,000,000
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, Noncurrent	526,000,000			526,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	526,000,000			526,000,000
Unrecognized Equity Carrying Costs	43,000,000			43,000,000
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%
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 Power Co [Member] | Requested Sporn 5 Shutdown and Proposed Distribution Rider [Member]
Rate Matters (Textuals) [Abstract]
Sporn Five Incurred Closure Costs as of December 2010	59,000,000			59,000,000
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]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	13,000,000			13,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	13,000,000			13,000,000
Unrecognized Equity Carrying Costs	16,000,000			16,000,000
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 2009	30,000,000			30,000,000
Unrecognized Equity Carrying Costs Related to Ormet Interim Arrangement as of September 2009	1,000,000			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 2009	34,000,000			34,000,000
Unrecognized Equity Carrying Costs Related to Ormet Interim Arrangement as of September 2009	1,000,000			1,000,000
Columbus Southern Power Co [Member] | Ohio Distribution Base Rate Case [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	100,000,000			100,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	100,000,000			100,000,000
Unrecognized Equity Carrying Costs	61,000,000			61,000,000
Requested Base Rate Increase				34,000,000
Requested Recovery of Projected Distribution Regulatory Assets	216,000,000			216,000,000
Projected Unrecognized Equity Carrying Costs	102,000,000			102,000,000
Ohio Power Co [Member] | Ohio Distribution Base Rate Case [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	64,000,000			64,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	64,000,000			64,000,000
Unrecognized Equity Carrying Costs	45,000,000			45,000,000
Requested Base Rate Increase				60,000,000
Requested Recovery of Projected Distribution Regulatory Assets	159,000,000			159,000,000
Projected Unrecognized Equity Carrying Costs	84,000,000			84,000,000
Ohio Distribution Base Rate Case [Member] | Columbus Southern Power Co, Ohio Power Co [Member]
Rate Matters (Textuals) [Abstract]
Requested Return on Equity				11.15%
Columbus Southern Power Co [Member] | Economic Development Rider [Member]
Rate Matters (Textuals) [Abstract]
Costs Incurred				59,000,000
Costs Collected				50,000,000
Columbus Southern Power Co [Member] | Economic Development Rider [Member] | Remaining Economic Development Rider Costs to Be Collected [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	9,000,000			9,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	9,000,000			9,000,000
Ohio Power Co [Member] | Economic Development Rider [Member]
Rate Matters (Textuals) [Abstract]
Costs Incurred				55,000,000
Costs Collected				39,000,000
Ohio Power Co [Member] | Economic Development Rider [Member] | Remaining Economic Development Rider Costs to Be Collected [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	16,000,000			16,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	16,000,000			16,000,000
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 Interest	1,000,000			1,000,000
Regulatory Liabilities, Noncurrent	2,000,000			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 Interest	1,000,000			1,000,000
Regulatory Liabilities, Noncurrent	2,000,000			2,000,000
Southwestern Electric Power Co [Member] | Turk Plant [Member]
Rate Matters (Textuals) [Abstract]
Subsidiary's Ownership Percentage	73.00%			73.00%
Total Current Estimated Generation Cost				1,700,000,000
Total Current Estimated Transmission Costs	124,000,000			124,000,000
Subsidiary's Estimated Share of the Generation Cost				1,300,000,000
Subsidiary's Estimated Share of the Transmission Costs	124,000,000			124,000,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners				175,000,000
Contractual Construction Commitments Of Joint Owners And Subsidiary	211,000,000			211,000,000
Transmission Contractual Construction Commitments Of Subsidiary	11,000,000			11,000,000
Subsidiary Share of Contractual Construction Commitments	157,000,000			157,000,000
Estimated Cancellation Fee Which Shall be Incurred by Joint Owners and Subsidiary If the Plant is Cancelled	101,000,000			101,000,000
Transmission Cancellation Fees Which Shall be Incurred by Subsidiary	1,000,000			1,000,000
Subsidiary's Share of Cancellation Fees Which Shall be Incurred if the Plant is Cancelled	74,000,000			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
Construction in Progress, Gross	1,200,000,000			1,200,000,000
Southwestern Electric Power Co [Member] | Turk Plant [Member] | Electric Transmission [Member]
Rate Matters (Textuals) [Abstract]
Construction in Progress, Gross	79,000,000			79,000,000
Texas Restructuring Appeals [Member] | AEP Texas Central Co [Member]
Rate Matters (Textuals) [Abstract]
Net Recoverable Texas Stranded Generation Costs				2,500,000,000
Refund of Other Texas Net True-up Regulatory Liabilities				375,000,000
Estimated Amount of Recovery on Remand				420,000,000
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 Could Have Been Had They Accrued Interest on the Tax Benefit				27,000,000
Contingency to Pay Accumulated Deferred Investment Tax Credits	101,000,000			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%
Renewable Portfolio Standards Incentive Included in Return on Equity	0.50%			0.50%
Amount of Increase in Depreciation Expense Proposed to be Mitigated in Recovery Until Next Base Case Filing	51,000,000			51,000,000
Requested Net Base Rate Increase	75,000,000			75,000,000
Attorney General Witness Recommended Reduction in Capacity Charges	80,000,000			80,000,000
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Environmental Rate Adjustment Clause [Member]
Rate Matters (Textuals) [Abstract]
Unrecognized Equity Carrying Costs	15,000,000			15,000,000
Requested Recovery of Rate Adjustment Clause Costs	38,000,000			38,000,000
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Deferred Wind Power Costs [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	32,000,000			32,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	32,000,000			32,000,000
Appalachian Power Co [Member] | Rate Adjustment Clauses [Member] | Renewable Energy Program Rate Adjustment Clause [Member]
Rate Matters (Textuals) [Abstract]
Requested Recovery of Rate Adjustment Clause Costs	6,000,000			6,000,000
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%			10.00%
Approved Deferral of Cost Reduction Initiative Expenses				15,000,000
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, Noncurrent	19,000,000	[1]		19,000,000	[1]		60,000,000	[1]
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	19,000,000	[1]		19,000,000	[1]		60,000,000	[1]
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 Recovery	9,000,000			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 Recovery	2,000,000			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 Recovery	9,000,000			9,000,000
Appalachian Power Co [Member] | Expanded Net Energy Charge [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	387,000,000			387,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	387,000,000			387,000,000
Unrecognized Equity Carrying Costs	8,000,000			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%			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
Amount Of Construction Surcharges Agreed To In Settlement Agreement For Second Year Increase				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 Third Year Increase in Construction Surcharges				8,000,000
Approved Third Year 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 Years	355,000,000			355,000,000
Public Service Co Of Oklahoma [Member] | Fuel and Purchased Power 2008 [Member]
Rate Matters (Textuals) [Abstract]
Current Shareholder Percentage of Off-System Sales Margins Sharing in Oklahoma				25.00%
Intervenors Proposed New Shareholder Percentage of Off-System Sales Margins Sharing in Oklahoma				10.00%
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			20,000,000
Amount of Estimated Interest Included in Payment	5,000,000			5,000,000
Potential Receipt of Payment if Compliance Filing is Accepted	10,000,000			10,000,000
Amount of Estimated Interest Included in Potential Receipt of Payment	3,000,000			3,000,000
Amount of FERC approved settlements applicable to SECA revenue.	112,000,000			112,000,000
Remaining Amount of Contested SECA Revenues				108,000,000
Appalachian Power Co [Member] | Product Validation Facility [Member]
Rate Matters (Textuals) [Abstract]
Write-off of Regulatory Asset, Pretax	41,000,000			41,000,000
Write-off of Regulatory Asset, Net of Tax	26,000,000			26,000,000
Appalachian Power Co [Member] | Carbon Capture and Sequestration Project [Member]
Rate Matters (Textuals) [Abstract]
Costs Incurred				30,000,000
Maximum Amount of Department of Energy Funding	334,000,000			334,000,000
Department of Energy Eligible Funding Received				10,000,000
Net Cost of Carbon Capture Project				20,000,000
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
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, Noncurrent	25,000,000			25,000,000			25,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	25,000,000			25,000,000			25,000,000
Appalachian Power Co [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	1,506,936,000			1,506,936,000			1,486,625,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	1,506,936,000			1,506,936,000			1,486,625,000
Regulatory Liabilities, Noncurrent	566,314,000			566,314,000			562,381,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners	1,212,000		128,000	2,095,000		1,291,000
Construction in Progress, Gross	241,339,000			241,339,000			562,280,000
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, Noncurrent	65,000,000			65,000,000			56,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	65,000,000			65,000,000			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, Noncurrent	38,000,000			38,000,000			29,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	38,000,000			38,000,000			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, Noncurrent	13,000,000			13,000,000			13,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	13,000,000			13,000,000			13,000,000
Southwestern Electric Power Co [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	349,174,000			349,174,000			332,698,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	349,174,000			349,174,000			332,698,000
Regulatory Liabilities, Noncurrent	417,571,000			417,571,000			393,673,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners	11,573,000		12,462,000	22,169,000		27,979,000
Construction in Progress, Gross	1,268,429,000			1,268,429,000			1,071,603,000
Ohio Power Co [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	1,004,684,000			1,004,684,000			934,011,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	1,004,684,000			1,004,684,000			934,011,000
Regulatory Liabilities, Noncurrent	131,188,000			131,188,000			126,403,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners	961,000		986,000	1,393,000		2,017,000
Construction in Progress, Gross	139,690,000			139,690,000			153,110,000
Columbus Southern Power Co [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	313,651,000			313,651,000			298,111,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	313,651,000			313,651,000			298,111,000
Regulatory Liabilities, Noncurrent	168,346,000			168,346,000			163,888,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners	547,000		314,000	1,318,000		1,235,000
Construction in Progress, Gross	149,955,000			149,955,000			172,793,000
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, Noncurrent	9,000,000	[2]		9,000,000	[2]		8,000,000	[2]
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	9,000,000	[2]		9,000,000	[2]		8,000,000	[2]
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, Noncurrent	4,000,000	[2]		4,000,000	[2]		4,000,000	[2]
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	4,000,000	[2]		4,000,000	[2]		4,000,000	[2]
Public Service Co Of Oklahoma [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	261,716,000			261,716,000			263,545,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	261,716,000			261,716,000			263,545,000
Regulatory Liabilities, Noncurrent	329,669,000			329,669,000			336,961,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners	284,000		119,000	650,000		366,000
Construction in Progress, Gross	43,372,000			43,372,000			59,091,000
Public Service Co Of Oklahoma [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, Noncurrent	18,000,000	[3]		18,000,000	[3]		0	[3]
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	18,000,000	[3]		18,000,000	[3]		0	[3]
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, Noncurrent	0	[3]		0	[3]		17,000,000	[3]
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	0	[3]		0	[3]		17,000,000	[3]
Indiana Michigan Power Co [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	519,181,000			519,181,000			556,254,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	519,181,000			519,181,000			556,254,000
Regulatory Liabilities, Noncurrent	868,919,000			868,919,000			852,197,000
Subsidiary's Capitalized AFUDC and Interest Excluding Costs Attributable to Joint Owners				7,440,000		9,002,000
Construction in Progress, Gross	338,627,000			338,627,000			301,534,000
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, Noncurrent	60,000,000	[2]		60,000,000	[2]		59,000,000	[2]
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	60,000,000	[2]		60,000,000	[2]		59,000,000	[2]
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, Noncurrent	31,000,000	[2]		31,000,000	[2]		30,000,000	[2]
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	31,000,000	[2]		31,000,000	[2]		30,000,000	[2]
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, Noncurrent	61,000,000	[2]		61,000,000	[2]		55,000,000	[2]
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	61,000,000	[2]		61,000,000	[2]		55,000,000	[2]
Appalachian Power Co Kingsport Power Co Southwestern Electric 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, Noncurrent	28,000,000			28,000,000			28,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	28,000,000			28,000,000			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, Noncurrent	7,000,000			7,000,000			7,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	7,000,000			7,000,000			7,000,000
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, Noncurrent	5,000,000			5,000,000			4,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	5,000,000			5,000,000			4,000,000
Regulatory Assets Not Yet Being Recovered [Member]
Regulatory Assets Not Being Recovered [Abstract]
Regulatory Assets, Noncurrent	383,000,000			383,000,000			395,000,000
Rate Matters (Textuals) [Abstract]
Regulatory Assets, Noncurrent	$ 383,000,000			$ 383,000,000			$ 395,000,000

[1] APCo wrote off a portion of the Mountaineer Carbon Capture and Storage Product Validation Facility as denied for recovery by the WVPSC in March 2011. See "Mountaineer Carbon Capture and Storage Project Product Validation Facility" section below.

[2] Requested to be recovered in a distribution asset recovery rider. See the "2011 Ohio Distribution Base Rate Case" section below.

[3] In June 2011, an order was received approving recovery of PSO storm costs and associated carrying costs with recovery to begin in August 2011. Starting in the second quarter of 2011, and in accordance with the order received from the OCC, PSO recorded a return on its storm related costs.