Commitments, Guarantees and Contingencies (Details) (USD $)	9 Months Ended
	Sep. 30, 2012
Letters of Credit [Member]
Maximum Future Payments for Letters of Credit [Abstract]
Maximum Future Payments for Letters of Credit	$ 132,000,000
Pollution Control Bonds Supported by Bilateral Letters of Credit [Abstract]
Variable Rate PCBs Supported	402,000,000
Bilateral Letters of Credit	407,000,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Credit Facilities, Total	3,250,000,000
Letters of Credit Limit	1,350,000,000
Maximum Future Payments for Letters of Credit	132,000,000
Variable Rate PCBs Supported	402,000,000
Bilateral Letters of Credit	407,000,000
Master Lease Agreements [Member]
Maximum Potential Loss on Master Lease Agreements [Abstract]
Max Potential Loss on Master Lease Agreements	18,000,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Max Potential Loss on Master Lease Agreements	18,000,000
Guarantees of Third Party Obligations [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Guarantees of Mine Reclamation, Amount	115,000,000
Estimated Final Cost Mine Reclamation	58,000,000
Total Amount Collected through a Rider for Final Mine Closure and Reclamation Costs	58,000,000
Amount Collected through a Rider for Final Mine Closure - Other Current Liabilities	10,000,000
Amount Collected through a Rider for Final Mine Closure - Other Liabilities Noncurrent	7,000,000
Amount Collected through a Rider for Final Mine Closure - ARO Noncurrent	41,000,000
Indiana Michigan Power Co [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Letters of Credit Limit	110,000,000
Indiana Michigan Power Co [Member] | Letters of Credit [Member]
Maximum Future Payments for Letters of Credit [Abstract]
Maximum Future Payments for Letters of Credit	150,000
Pollution Control Bonds Supported by Bilateral Letters of Credit [Abstract]
Variable Rate PCBs Supported	77,000,000
Bilateral Letters of Credit	77,886,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Maximum Future Payments for Letters of Credit	150,000
Variable Rate PCBs Supported	77,000,000
Bilateral Letters of Credit	77,886,000
Indiana Michigan Power Co [Member] | Master Lease Agreements [Member]
Maximum Potential Loss on Master Lease Agreements [Abstract]
Max Potential Loss on Master Lease Agreements	2,426,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Max Potential Loss on Master Lease Agreements	2,426,000
Future Minimum Lease Obligation for Remaining Railcars	15,000,000
Guaranteed Sales Proceeds Percentage of Fair Value to Lessor Current Term	84.00%
Guaranteed Sales Proceeds Percentage of Fair Value to Lessor End of Max Lease Term	77.00%
Maximum Potential Loss on Guarantee of Return-and-Sale Option	12,000,000
Southwestern Electric Power Co [Member] | Letters of Credit [Member]
Maximum Future Payments for Letters of Credit [Abstract]
Maximum Future Payments for Letters of Credit	4,448,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Maximum Future Payments for Letters of Credit	4,448,000
Southwestern Electric Power Co [Member] | Master Lease Agreements [Member]
Maximum Potential Loss on Master Lease Agreements [Abstract]
Max Potential Loss on Master Lease Agreements	2,559,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Max Potential Loss on Master Lease Agreements	2,559,000
Future Minimum Lease Obligation for Remaining Railcars	17,000,000
Guaranteed Sales Proceeds Percentage of Fair Value to Lessor Current Term	84.00%
Guaranteed Sales Proceeds Percentage of Fair Value to Lessor End of Max Lease Term	77.00%
Maximum Potential Loss on Guarantee of Return-and-Sale Option	13,000,000
Southwestern Electric Power Co [Member] | Guarantees of Third Party Obligations [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Guarantees of Mine Reclamation, Amount	115,000,000
Estimated Final Cost Mine Reclamation	58,000,000
Total Amount Collected through a Rider for Final Mine Closure and Reclamation Costs	58,000,000
Amount Collected through a Rider for Final Mine Closure - Other Current Liabilities	10,000,000
Amount Collected through a Rider for Final Mine Closure - Other Liabilities Noncurrent	7,000,000
Amount Collected through a Rider for Final Mine Closure - ARO Noncurrent	41,000,000
Ohio Power Co [Member] | Letters of Credit [Member]
Maximum Future Payments for Letters of Credit [Abstract]
Maximum Future Payments for Letters of Credit	2,102,000
Pollution Control Bonds Supported by Bilateral Letters of Credit [Abstract]
Variable Rate PCBs Supported	50,000,000
Bilateral Letters of Credit	50,575,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Maximum Future Payments for Letters of Credit	2,102,000
Variable Rate PCBs Supported	50,000,000
Bilateral Letters of Credit	50,575,000
Ohio Power Co [Member] | Master Lease Agreements [Member]
Maximum Potential Loss on Master Lease Agreements [Abstract]
Max Potential Loss on Master Lease Agreements	3,556,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Max Potential Loss on Master Lease Agreements	3,556,000
Appalachian Power Co [Member] | Letters of Credit [Member]
Pollution Control Bonds Supported by Bilateral Letters of Credit [Abstract]
Variable Rate PCBs Supported	229,650,000
Bilateral Letters of Credit	232,293,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Variable Rate PCBs Supported	229,650,000
Bilateral Letters of Credit	232,293,000
Appalachian Power Co [Member] | Master Lease Agreements [Member]
Maximum Potential Loss on Master Lease Agreements [Abstract]
Max Potential Loss on Master Lease Agreements	3,132,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Max Potential Loss on Master Lease Agreements	3,132,000
Public Service Co Of Oklahoma [Member] | Master Lease Agreements [Member]
Maximum Potential Loss on Master Lease Agreements [Abstract]
Max Potential Loss on Master Lease Agreements	1,167,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Max Potential Loss on Master Lease Agreements	1,167,000
Superfund and State Remediation [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Expense Recorded Due to Remediation Work Remaining Provision	10,000,000
Superfund and State Remediation [Member] | Indiana Michigan Power Co [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Expense Recorded Due to Remediation Work Remaining Provision	10,000,000
Cook Plant Unit 1 Fire and Shutdown [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Estimated Repair of the Property Damage and Rotor Replacement Cost	400,000,000
Recoverable Amount Under the Property Insurance Policy	64,000,000
Received Partial Payments for the Cost Incurred to Repair Property Damage	203,000,000
Insurance Recovery Recorded in Revenues During the Outage Period	185,000,000
Cook Plant Unit 1 Fire and Shutdown [Member] | Indiana Michigan Power Co [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Estimated Repair of the Property Damage and Rotor Replacement Cost	400,000,000
Recoverable Amount Under the Property Insurance Policy	64,000,000
Received Partial Payments for the Cost Incurred to Repair Property Damage	203,000,000
Insurance Recovery Recorded in Revenues During the Outage Period	185,000,000
Alaskan Villages Claim [Member] | From [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Amount Required for Relocation of the Village	95,000,000
Alaskan Villages Claim [Member] | To [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Amount Required for Relocation of the Village	$ 400,000,000