Sustainable Cost Reductions (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2013	Dec. 31, 2012
Sustainable Cost Reductions [Abstract]
Beginning Balance	$ 2,000	$ 25,000
Incurred	16,000
Settled	(30,000)
Adjustments	(9,000)
Remaining Balance	2,000	25,000
Sustainable Cost Reductions Text [Abstract]
Severance Costs		47,000
Utility Operations [Member]
Sustainable Cost Reductions Text [Abstract]
Severance Costs Percentage	95.00%
Appalachian Power Co [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	33	1,321
Expense Allocation from AEPSC	1,017
Incurred	0
Settled	(1,575)
Adjustments	(730)
Remaining Balance	33	1,321
Sustainable Cost Reductions Text [Abstract]
Severance Costs		8,472
Indiana Michigan Power Co [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	39	1,357
Expense Allocation from AEPSC	736
Incurred	0
Settled	(1,681)
Adjustments	(373)
Remaining Balance	39	1,357
Sustainable Cost Reductions Text [Abstract]
Severance Costs		5,678
Ohio Power Co [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	451	3,450
Expense Allocation from AEPSC	1,354
Incurred	6,114
Settled	(8,837)
Adjustments	(1,630)
Remaining Balance	451	3,450
Sustainable Cost Reductions Text [Abstract]
Severance Costs		13,498
Public Service Co Of Oklahoma [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	23	652
Expense Allocation from AEPSC	325
Incurred	0
Settled	(483)
Adjustments	(471)
Remaining Balance	23	652
Sustainable Cost Reductions Text [Abstract]
Severance Costs		3,675
Southwestern Electric Power Co [Member]
Sustainable Cost Reductions [Abstract]
Beginning Balance	34	627
Expense Allocation from AEPSC	622
Incurred	0
Settled	(1,620)
Adjustments	405
Remaining Balance	34	627
Sustainable Cost Reductions Text [Abstract]
Severance Costs		$ 5,709

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Expense allocation from AEPSC.

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Severance costs percentage calculated by dividing the adjusted severance expense for the utility segment by the total adjusted severance expense.

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No definition available.

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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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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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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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