Sustainable Cost Reductions (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Sustainable Cost Reductions [Abstract]
Beginning Balance	$ 15,000	$ 25,000
Incurred	16,000
Settled	(19,000)
Adjustments	(7,000)
Remaining Balance	15,000	25,000
Sustainable Cost Reductions Text [Abstract]
Severance Costs		47,000
Appalachian Power Co [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	224	1,321
Expense Allocation from AEPSC	1,266
Incurred	0
Settled	(1,825)
Adjustments	(538)
Remaining Balance	224	1,321
Sustainable Cost Reductions Text [Abstract]
Severance Costs		8,472
Indiana Michigan Power Co [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	58	1,357
Expense Allocation from AEPSC	891
Incurred	0
Settled	(2,047)
Adjustments	(143)
Remaining Balance	58	1,357
Sustainable Cost Reductions Text [Abstract]
Severance Costs		5,678
Ohio Power Co [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	6,192	3,450
Expense Allocation from AEPSC	1,709
Incurred	6,114
Settled	(3,163)
Adjustments	(1,918)
Remaining Balance	6,192	3,450
Sustainable Cost Reductions Text [Abstract]
Severance Costs		13,498
Public Service Co Of Oklahoma [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	26	652
Expense Allocation from AEPSC	444
Incurred	0
Settled	(598)
Adjustments	(472)
Remaining Balance	26	652
Sustainable Cost Reductions Text [Abstract]
Severance Costs		3,675
Southwestern Electric Power Co [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	140	627
Expense Allocation from AEPSC	803
Incurred	0
Settled	(1,695)
Adjustments	405
Remaining Balance	140	627
Sustainable Cost Reductions Text [Abstract]
Severance Costs		$ 5,709

Amount of costs incurred to date for the specified type of restructuring cost.

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Amount of any reversal and other adjustment made during the period to the amount of a previously accrued liability for a specified type of restructuring cost, excluding adjustments for costs incurred during the period, costs settled during the period, and foreign currency translation adjustments.

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- Definition

The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

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