Business Segments (Details) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011		Dec. 31, 2011
Revenues from:
External Customers	$ 3,551,000,000		$ 3,609,000,000		$ 7,176,000,000		$ 7,339,000,000
Other Operating Segments	0		0		0		0
TOTAL REVENUES	3,551,000,000		3,609,000,000		7,176,000,000		7,339,000,000
NET INCOME (LOSS)	363,000,000		353,000,000		753,000,000		708,000,000
Balance Sheet Information
Total Property, Plant and Equipment	56,784,000,000				56,784,000,000				55,670,000,000
Accumulated Depreciation and Amortization	18,956,000,000				18,956,000,000				18,699,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	37,828,000,000				37,828,000,000				36,971,000,000
Total Assets	53,421,000,000				53,421,000,000				52,223,000,000
Utility Operations [Member]
Revenues from:
External Customers	3,234,000,000		3,359,000,000		6,596,000,000		6,856,000,000
Other Operating Segments	24,000,000		29,000,000		47,000,000		56,000,000
TOTAL REVENUES	3,258,000,000		3,388,000,000		6,643,000,000		6,912,000,000
NET INCOME (LOSS)	365,000,000		350,000,000		749,000,000		724,000,000
Balance Sheet Information
Total Property, Plant and Equipment	55,289,000,000				55,289,000,000				54,396,000,000
Accumulated Depreciation and Amortization	18,627,000,000				18,627,000,000				18,393,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	36,662,000,000				36,662,000,000				36,003,000,000
Total Assets	50,983,000,000				50,983,000,000				50,093,000,000
Transmission Operations [Member]
Revenues from:
External Customers	1,000,000		1,000,000		2,000,000		1,000,000
Other Operating Segments	1,000,000		(1,000,000)		3,000,000		(1,000,000)
TOTAL REVENUES	2,000,000		0		5,000,000		0
NET INCOME (LOSS)	8,000,000		6,000,000		17,000,000		10,000,000
Balance Sheet Information
Total Property, Plant and Equipment	508,000,000				508,000,000				323,000,000
Accumulated Depreciation and Amortization	2,000,000				2,000,000				0
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	506,000,000				506,000,000				323,000,000
Total Assets	865,000,000				865,000,000				594,000,000
Nonutility Operations - AEP River Operations [Member]
Revenues from:
External Customers	163,000,000		162,000,000		335,000,000		329,000,000
Other Operating Segments	4,000,000		4,000,000		11,000,000		9,000,000
TOTAL REVENUES	167,000,000		166,000,000		346,000,000		338,000,000
NET INCOME (LOSS)	3,000,000		(1,000,000)		12,000,000		6,000,000
Balance Sheet Information
Total Property, Plant and Equipment	624,000,000				624,000,000				608,000,000
Accumulated Depreciation and Amortization	150,000,000				150,000,000				136,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	474,000,000				474,000,000				472,000,000
Total Assets	650,000,000				650,000,000				659,000,000
Nonutility Operations - Generation and Marketing [Member]
Revenues from:
External Customers	148,000,000		79,000,000		233,000,000		141,000,000
Other Operating Segments	0		0		0		1,000,000
TOTAL REVENUES	148,000,000		79,000,000		233,000,000		142,000,000
NET INCOME (LOSS)	(5,000,000)		11,000,000		(6,000,000)		12,000,000
Balance Sheet Information
Total Property, Plant and Equipment	618,000,000				618,000,000				590,000,000
Accumulated Depreciation and Amortization	232,000,000				232,000,000				219,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	386,000,000				386,000,000				371,000,000
Total Assets	1,030,000,000				1,030,000,000				868,000,000
All Other [Member]
Revenues from:
External Customers	5,000,000	[1]	8,000,000	[1]	10,000,000	[1]	12,000,000	[1]
Other Operating Segments	1,000,000	[1]	2,000,000	[1]	3,000,000	[1]	3,000,000	[1]
TOTAL REVENUES	6,000,000	[1]	10,000,000	[1]	13,000,000	[1]	15,000,000	[1]
NET INCOME (LOSS)	(8,000,000)	[1]	(13,000,000)	[1]	(19,000,000)	[1]	(44,000,000)	[1]
Balance Sheet Information
Total Property, Plant and Equipment	11,000,000	[1]			11,000,000	[1]			11,000,000	[1]
Accumulated Depreciation and Amortization	10,000,000	[1]			10,000,000	[1]			10,000,000	[1]
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	1,000,000	[1]			1,000,000	[1]			1,000,000	[1]
Total Assets	16,638,000,000	[1]			16,638,000,000	[1]			16,751,000,000	[1]
Reconciling Adjustments [Member]
Revenues from:
External Customers	0		0		0		0
Other Operating Segments	(30,000,000)		(34,000,000)		(64,000,000)		(68,000,000)
TOTAL REVENUES	(30,000,000)		(34,000,000)		(64,000,000)		(68,000,000)
NET INCOME (LOSS)	0		0		0		0
Balance Sheet Information
Total Property, Plant and Equipment	(266,000,000)	[2]			(266,000,000)	[2]			(258,000,000)	[2]
Accumulated Depreciation and Amortization	(65,000,000)	[2]			(65,000,000)	[2]			(59,000,000)	[2]
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	(201,000,000)	[2]			(201,000,000)	[2]			(199,000,000)	[2]
Total Assets	$ (16,745,000,000)	[2],[3]			$ (16,745,000,000)	[2],[3]			$ (16,742,000,000)	[2],[3]

[1] All Other includes: Parent's guarantee revenue received from affiliates, investment income, interest income and interest expense and other nonallocated costs. Forward natural gas contracts that were not sold with our natural gas pipeline and storage operations in 2004 and 2005. These contracts were financial derivatives which settled and expired in the fourth quarter of 2011. Revenue sharing related to the Plaquemine Cogeneration Facility which ended in the fourth quarter of 2011.

[2] Includes eliminations due to an intercompany capital lease.

[3] Reconciling Adjustments for Total Assets primarily include the elimination of intercompany advances to affiliates and intercompany accounts receivable along with the elimination of AEP's investments in subsidiary companies.