Business Segments (Details) (USD $)	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Dec. 31, 2012
Revenues from:
External Customers	$ 3,826,000,000		$ 3,625,000,000
Other Operating Segments	0		0
TOTAL REVENUES	3,826,000,000		3,625,000,000
NET INCOME (LOSS)	364,000,000		390,000,000
Balance Sheet Information
Total Property, Plant and Equipment	58,075,000,000				57,454,000,000
Accumulated Depreciation and Amortization	18,945,000,000				18,691,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	39,130,000,000				38,763,000,000
Total Assets	54,550,000,000				54,367,000,000
Utility Operations [Member]
Revenues from:
External Customers	3,486,000,000		3,362,000,000
Other Operating Segments	31,000,000		23,000,000
TOTAL REVENUES	3,517,000,000		3,385,000,000
NET INCOME (LOSS)	349,000,000		384,000,000
Balance Sheet Information
Total Property, Plant and Equipment	56,152,000,000				55,707,000,000
Accumulated Depreciation and Amortization	18,585,000,000				18,344,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	37,567,000,000				37,363,000,000
Total Assets	51,534,000,000				51,477,000,000
Transmission Operations [Member]
Revenues from:
External Customers	3,000,000		1,000,000
Other Operating Segments	5,000,000		2,000,000
TOTAL REVENUES	8,000,000		3,000,000
NET INCOME (LOSS)	13,000,000		9,000,000
Balance Sheet Information
Total Property, Plant and Equipment	921,000,000				748,000,000
Accumulated Depreciation and Amortization	5,000,000				4,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	916,000,000				744,000,000
Total Assets	1,409,000,000				1,216,000,000
Nonutility Operations - AEP River Operations [Member]
Revenues from:
External Customers	128,000,000		172,000,000
Other Operating Segments	5,000,000		7,000,000
TOTAL REVENUES	133,000,000		179,000,000
NET INCOME (LOSS)	(2,000,000)		9,000,000
Balance Sheet Information
Total Property, Plant and Equipment	638,000,000				636,000,000
Accumulated Depreciation and Amortization	169,000,000				161,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	469,000,000				475,000,000
Total Assets	640,000,000				670,000,000
Nonutility Operations - Generation and Marketing [Member]
Revenues from:
External Customers	206,000,000		85,000,000
Other Operating Segments	0		0
TOTAL REVENUES	206,000,000		85,000,000
NET INCOME (LOSS)	7,000,000		(1,000,000)
Balance Sheet Information
Total Property, Plant and Equipment	625,000,000				621,000,000
Accumulated Depreciation and Amortization	254,000,000				246,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	371,000,000				375,000,000
Total Assets	1,003,000,000				1,005,000,000
All Other [Member]
Revenues from:
External Customers	3,000,000	[1]	5,000,000	[1]
Other Operating Segments	2,000,000	[1]	2,000,000	[1]
TOTAL REVENUES	5,000,000	[1]	7,000,000	[1]
NET INCOME (LOSS)	(3,000,000)	[1]	(11,000,000)	[1]
Balance Sheet Information
Total Property, Plant and Equipment	8,000,000	[1]			8,000,000	[1]
Accumulated Depreciation and Amortization	7,000,000	[1]			7,000,000	[1]
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	1,000,000	[1]			1,000,000	[1]
Total Assets	17,795,000,000	[1]			17,191,000,000	[1]
Reconciling Adjustments [Member]
Revenues from:
External Customers	0		0
Other Operating Segments	(43,000,000)		(34,000,000)
TOTAL REVENUES	(43,000,000)		(34,000,000)
NET INCOME (LOSS)	0		0
Balance Sheet Information
Total Property, Plant and Equipment	(269,000,000)	[2]			(266,000,000)	[2]
Accumulated Depreciation and Amortization	(75,000,000)	[2]			(71,000,000)	[2]
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	(194,000,000)	[2]			(195,000,000)	[2]
Total Assets	$ (17,831,000,000)	[2],[3]			$ (17,192,000,000)	[2],[3]

[1] All Other includes Parent's guarantee revenue received from affiliates, investment income, interest income and interest expense and other nonallocated costs.

[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.