Business Segments (Details) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013		Dec. 31, 2013
Reportable Segment Information
Revenues	$ 4,044,000,000		$ 3,582,000,000		$ 8,692,000,000		$ 7,408,000,000
NET INCOME (LOSS)	391,000,000		339,000,000		952,000,000		703,000,000
Balance Sheet Information
Total Property, Plant and Equipment	62,065,000,000				62,065,000,000				60,285,000,000
Accumulated Depreciation and Amortization	19,792,000,000				19,792,000,000				19,288,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	42,273,000,000				42,273,000,000				40,997,000,000
Total Assets	57,620,000,000				57,620,000,000				56,414,000,000
Long-term Debt Due Within One Year - Affiliated	0				0				0
Long-term Debt Due Within One Year	2,524,000,000				2,524,000,000				1,549,000,000
Long-term Debt - Affiliated	0				0				0
Long-term Debt	15,601,000,000				15,601,000,000				16,828,000,000
Total Long-term Debt Outstanding	18,125,000,000				18,125,000,000				18,377,000,000
Reconciling Adjustments [Member]
Reportable Segment Information
NET INCOME (LOSS)	0		0		0		0
Balance Sheet Information
Total Property, Plant and Equipment	(272,000,000)	[1]			(272,000,000)	[1]			(269,000,000)	[1]
Accumulated Depreciation and Amortization	(92,000,000)	[1]			(92,000,000)	[1]			(85,000,000)	[1]
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	(180,000,000)	[1]			(180,000,000)	[1]			(184,000,000)	[1]
Total Assets	(19,283,000,000)	[1],[2]			(19,283,000,000)	[1],[2]			(19,531,000,000)	[1],[2]
Long-term Debt Due Within One Year - Affiliated	(256,000,000)				(256,000,000)				(184,000,000)
Long-term Debt Due Within One Year	0				0				0
Long-term Debt - Affiliated	(52,000,000)				(52,000,000)				(279,000,000)
Long-term Debt	0				0				0
Total Long-term Debt Outstanding	(308,000,000)				(308,000,000)				(463,000,000)
Vertically Integrated Utilities [Member]
Reportable Segment Information
Sales Revenue, Net	2,236,000,000	[3]	2,176,000,000		4,785,000,000	[3]	4,532,000,000
Revenues	2,252,000,000		2,302,000,000		4,838,000,000		4,817,000,000
NET INCOME (LOSS)	155,000,000		153,000,000		434,000,000		334,000,000
Balance Sheet Information
Total Property, Plant and Equipment	38,390,000,000				38,390,000,000				37,545,000,000
Accumulated Depreciation and Amortization	12,562,000,000				12,562,000,000				12,250,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	25,828,000,000				25,828,000,000				25,295,000,000
Total Assets	33,024,000,000				33,024,000,000				32,791,000,000
Long-term Debt Due Within One Year - Affiliated	131,000,000				131,000,000				0
Long-term Debt Due Within One Year	1,382,000,000				1,382,000,000				720,000,000
Long-term Debt - Affiliated	20,000,000				20,000,000				151,000,000
Long-term Debt	8,445,000,000				8,445,000,000				9,265,000,000
Total Long-term Debt Outstanding	9,978,000,000				9,978,000,000				10,136,000,000
Vertically Integrated Utilities [Member] | Significant Reconciling Items [Member]
Reportable Segment Information
Sales Revenue, Net	16,000,000	[3]	126,000,000		53,000,000	[3]	285,000,000
Transmission And Distribution Companies [Member]
Reportable Segment Information
Sales Revenue, Net	1,064,000,000		1,019,000,000		2,225,000,000		2,109,000,000
Revenues	1,134,000,000		1,064,000,000		2,349,000,000		2,198,000,000
NET INCOME (LOSS)	90,000,000		75,000,000		187,000,000		162,000,000
Balance Sheet Information
Total Property, Plant and Equipment	12,554,000,000				12,554,000,000				12,143,000,000
Accumulated Depreciation and Amortization	3,407,000,000				3,407,000,000				3,342,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	9,147,000,000				9,147,000,000				8,801,000,000
Total Assets	13,859,000,000				13,859,000,000				14,165,000,000
Long-term Debt Due Within One Year - Affiliated	0				0				0
Long-term Debt Due Within One Year	448,000,000				448,000,000				697,000,000
Long-term Debt - Affiliated	0				0				0
Long-term Debt	5,306,000,000				5,306,000,000				5,360,000,000
Total Long-term Debt Outstanding	5,754,000,000				5,754,000,000				6,057,000,000
Transmission And Distribution Companies [Member] | Significant Reconciling Items [Member]
Reportable Segment Information
Sales Revenue, Net	70,000,000		45,000,000		124,000,000		89,000,000
AEP Transmission Holdco [Member]
Reportable Segment Information
Sales Revenue, Net	21,000,000		6,000,000		33,000,000		9,000,000
Revenues	57,000,000		19,000,000		85,000,000		27,000,000
NET INCOME (LOSS)	47,000,000		19,000,000		71,000,000		31,000,000
Balance Sheet Information
Total Property, Plant and Equipment	2,079,000,000				2,079,000,000				1,636,000,000
Accumulated Depreciation and Amortization	16,000,000				16,000,000				10,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	2,063,000,000				2,063,000,000				1,626,000,000
Total Assets	2,702,000,000				2,702,000,000				2,245,000,000
Long-term Debt Due Within One Year - Affiliated	0				0				0
Long-term Debt Due Within One Year	0				0				0
Long-term Debt - Affiliated	0				0				0
Long-term Debt	689,000,000				689,000,000				620,000,000
Total Long-term Debt Outstanding	689,000,000				689,000,000				620,000,000
AEP Transmission Holdco [Member] | Significant Reconciling Items [Member]
Reportable Segment Information
Sales Revenue, Net	36,000,000		13,000,000		52,000,000		18,000,000
Generation And Marketing [Member]
Reportable Segment Information
Sales Revenue, Net	573,000,000	[3]	298,000,000		1,394,000,000	[3]	556,000,000
Revenues	913,000,000		892,000,000		2,164,000,000		1,812,000,000
NET INCOME (LOSS)	98,000,000		(9,000,000)		261,000,000		76,000,000
Balance Sheet Information
Total Property, Plant and Equipment	8,345,000,000				8,345,000,000				8,277,000,000
Accumulated Depreciation and Amortization	3,514,000,000				3,514,000,000				3,409,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	4,831,000,000				4,831,000,000				4,868,000,000
Total Assets	6,301,000,000				6,301,000,000				6,426,000,000
Long-term Debt Due Within One Year - Affiliated	125,000,000				125,000,000				179,000,000
Long-term Debt Due Within One Year	687,000,000				687,000,000				126,000,000
Long-term Debt - Affiliated	32,000,000				32,000,000				118,000,000
Long-term Debt	239,000,000				239,000,000				664,000,000
Total Long-term Debt Outstanding	1,083,000,000				1,083,000,000				1,087,000,000
Generation And Marketing [Member] | Significant Reconciling Items [Member]
Reportable Segment Information
Sales Revenue, Net	340,000,000	[3]	594,000,000		770,000,000	[3]	1,256,000,000
AEP River Operations [Member]
Reportable Segment Information
Sales Revenue, Net	140,000,000		111,000,000		286,000,000		239,000,000
Revenues	160,000,000		117,000,000		325,000,000		250,000,000
NET INCOME (LOSS)	3,000,000		(9,000,000)		6,000,000		(11,000,000)
Balance Sheet Information
Total Property, Plant and Equipment	640,000,000				640,000,000				638,000,000
Accumulated Depreciation and Amortization	204,000,000				204,000,000				189,000,000
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	436,000,000				436,000,000				449,000,000
Total Assets	638,000,000				638,000,000				673,000,000
Long-term Debt Due Within One Year - Affiliated	0				0				5,000,000
Long-term Debt Due Within One Year	3,000,000				3,000,000				2,000,000
Long-term Debt - Affiliated	0				0				10,000,000
Long-term Debt	82,000,000				82,000,000				83,000,000
Total Long-term Debt Outstanding	85,000,000				85,000,000				100,000,000
AEP River Operations [Member] | Significant Reconciling Items [Member]
Reportable Segment Information
Sales Revenue, Net	20,000,000		6,000,000		39,000,000		11,000,000
All Other [Member]
Reportable Segment Information
Sales Revenue, Net	10,000,000	[4]	9,000,000	[4]	20,000,000	[4]	14,000,000	[4]
Revenues	22,000,000	[4]	21,000,000	[4]	48,000,000	[4]	39,000,000	[4]
NET INCOME (LOSS)	(2,000,000)	[4]	110,000,000	[4]	(7,000,000)	[4]	111,000,000	[4]
Balance Sheet Information
Total Property, Plant and Equipment	329,000,000	[4]			329,000,000	[4]			315,000,000	[4]
Accumulated Depreciation and Amortization	181,000,000	[4]			181,000,000	[4]			173,000,000	[4]
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET	148,000,000	[4]			148,000,000	[4]			142,000,000	[4]
Total Assets	20,379,000,000	[4]			20,379,000,000	[4]			19,645,000,000	[4]
Long-term Debt Due Within One Year - Affiliated	0	[4]			0	[4]			0	[4]
Long-term Debt Due Within One Year	4,000,000	[4]			4,000,000	[4]			4,000,000	[4]
Long-term Debt - Affiliated	0	[4]			0	[4]			0	[4]
Long-term Debt	840,000,000	[4]			840,000,000	[4]			836,000,000	[4]
Total Long-term Debt Outstanding	844,000,000	[4]			844,000,000	[4]			840,000,000	[4]
All Other [Member] | Significant Reconciling Items [Member]
Reportable Segment Information
Sales Revenue, Net	12,000,000	[4]	12,000,000	[4]	28,000,000	[4]	25,000,000	[4]
Consolidation, Eliminations [Member]
Reportable Segment Information
Sales Revenue, Net	0	[5]	(37,000,000)	[5]	(51,000,000)	[5]	(51,000,000)	[5]
Revenues	(494,000,000)		(833,000,000)		(1,117,000,000)		(1,735,000,000)
Consolidation, Eliminations [Member] | Reconciling Adjustments [Member]
Reportable Segment Information
Sales Revenue, Net	$ (494,000,000)		$ (796,000,000)		$ (1,066,000,000)		$ (1,684,000,000)

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

[2] 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.

[3] Includes the impact of the corporate separation of OPCo's generation assets and liabilities that took effect December 31, 2013, as well as the impact of the termination of the Interconnection Agreement effective January 1, 2014.

[4] Corporate and Other primarily includes management and professional services to AEP provided at cost to AEP subsidiaries and the purchasing of receivables from certain AEP utility subsidiaries. This segment also includes Parent's guarantee revenue received from affiliates, investment income, interest income and interest expense and other nonallocated costs.

[5] Reconciling Adjustments for External Customers primarily include eliminations as a result of corporate separation.