Significant Accounting Matters (Details) (USD $)	3 Months Ended			6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011	Jun. 30, 2012		Jun. 30, 2011	Dec. 31, 2011
Basic and Diluted EPS Calculations
Earnings Attributable to AEP Common Shareholders	$ 362,000,000		$ 352,000,000	$ 751,000,000		$ 705,000,000
Weighted Average Number of Basic AEP Common Shares Outstanding	484,500,029		481,928,494	484,164,065		481,538,549
Total Basic Earnings Per Share Attributable to AEP Common Shareholders	$ 0.75		$ 0.73	$ 1.55		$ 1.46
Weighted Average Dilutive Effect of:
Weighted Average Number of Diluted AEP Common Shares Outstanding	484,860,690		482,203,255	484,554,779		481,786,698
Total Diluted Earnings Per Share Arributable to AEP Common Shareholders	$ 0.75		$ 0.73	$ 1.55		$ 1.46
Amounts Attributable to AEP Common Shareholders
Net Income	362,000,000		352,000,000	751,000,000		705,000,000
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Securitization Bonds	2,389,000,000			2,389,000,000			1,688,000,000
Securitized Transition Assets	2,241,000,000			2,241,000,000			1,627,000,000
Percentage Ownership of "Allegheny Series" by a Nonaffiliated Company				100.00%
Antidilutive Shares Outstanding				10,000		70,050
Percentage Ownership in Rockport Plant Unit 1 by AEGCo				50.00%
Percentage Ownership in Rockport Plant Unit 2 Lease by AEGCo				50.00%
Percentage Ownership in Lawrenceburg Generating Station by AEGCo				100.00%
Sabine Mining Co [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	36,000,000		30,000,000	91,000,000		64,000,000
DCC Fuel [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Payments Made by I&M to DCC Fuel	42,000,000		38,000,000	59,000,000		43,000,000
Protected Cell of Energy Insurance Services, Inc. [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Insurance Premium Expense to Protected Cell	0		80,000	15,000,000		30,000,000
AEP Credit, Inc. [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Minimum Percentage of Equity AEP Provides				5.00%
Percentage of Short Term Borrowing Needs in Excess of Third Party Financings				20.00%
Dolet Hills Lignite Co, LLC [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	20,000,000		15,000,000	34,000,000		29,000,000
Percentage of VIE Sales of Lignite Produced				50.00%
Percentage of DHLC's Debt Guaranteed by Each SWEPCo and CLECO				50.00%
Percentage of Management Fee Received by SWEPCo from DHLC				100.00%
Capital Contribution from Parent [Member] | PATH West Virginia Transmission Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	19,000,000			19,000,000			19,000,000
Maximum Exposure	19,000,000			19,000,000			19,000,000
Capital Contribution from Parent [Member] | Dolet Hills Lignite Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	8,000,000			8,000,000			8,000,000
Maximum Exposure	8,000,000			8,000,000			8,000,000
Retained Earnings [Member] | PATH West Virginia Transmission Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	12,000,000			12,000,000			10,000,000
Maximum Exposure	12,000,000			12,000,000			10,000,000
Retained Earnings [Member] | Dolet Hills Lignite Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	1,000,000			1,000,000			1,000,000
Maximum Exposure	1,000,000			1,000,000			1,000,000
SWEPCo's Guarantee of Debt [Member] | Dolet Hills Lignite Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	0			0			0
Maximum Exposure	57,000,000			57,000,000			52,000,000
Total Investment [Member] | PATH West Virginia Transmission Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	31,000,000			31,000,000			29,000,000
Maximum Exposure	31,000,000			31,000,000			29,000,000
Total Investment [Member] | Dolet Hills Lignite Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	9,000,000			9,000,000			9,000,000
Maximum Exposure	66,000,000			66,000,000			61,000,000
Cleco Power, LLC [Member] | Dolet Hills Lignite Co, LLC [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Percentage of VIE Sales of Lignite Produced				50.00%
Appalachian Power Co [Member]
Basic and Diluted EPS Calculations
Earnings Attributable to AEP Common Shareholders	62,332,000		31,427,000	137,643,000		70,207,000
Amounts Attributable to AEP Common Shareholders
Net Income	62,332,000		31,427,000	137,643,000		70,207,000
Appalachian Power Co [Member] | Billings from AEPSC [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	43,894,000		47,352,000	82,440,000		92,293,000
Appalachian Power Co [Member] | Carrying Amount in AEPSC's Accounts Payable [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	16,077,000			16,077,000			20,812,000
Maximum Exposure	16,077,000			16,077,000			20,812,000
Indiana Michigan Power Co [Member]
Basic and Diluted EPS Calculations
Earnings Attributable to AEP Common Shareholders	29,810,000		31,301,000	69,031,000		76,643,000
Amounts Attributable to AEP Common Shareholders
Net Income	29,810,000		31,301,000	69,031,000		76,643,000
Indiana Michigan Power Co [Member] | DCC Fuel [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Payments Made by I&M to DCC Fuel	42,000,000		38,000,000	59,000,000		43,000,000
Indiana Michigan Power Co [Member] | Billings from AEPSC [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	31,377,000		31,006,000	57,484,000		62,834,000
Indiana Michigan Power Co [Member] | Billings from AEGCo [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	53,917,000		49,852,000	112,739,000		102,673,000
Indiana Michigan Power Co [Member] | Carrying Amount in AEPSC's Accounts Payable [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	11,526,000			11,526,000			13,741,000
Maximum Exposure	11,526,000			11,526,000			13,741,000
Indiana Michigan Power Co [Member] | Carrying Amount in AEGCo's Accounts Payable [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	20,912,000			20,912,000			25,731,000
Maximum Exposure	20,912,000			20,912,000			25,731,000
Ohio Power Co [Member]
Basic and Diluted EPS Calculations
Earnings Attributable to AEP Common Shareholders	101,423,000		141,986,000	252,253,000		307,748,000
Amounts Attributable to AEP Common Shareholders
Net Income	101,423,000		141,986,000	252,253,000		307,748,000
Ohio Power Co [Member] | Billings from AEPSC [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	67,490,000		72,992,000	120,935,000		136,869,000
Ohio Power Co [Member] | Billings from AEGCo [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	44,823,000		40,983,000	103,239,000		92,017,000
Ohio Power Co [Member] | Carrying Amount in AEPSC's Accounts Payable [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	19,233,000			19,233,000			29,823,000
Maximum Exposure	19,233,000			19,233,000			29,823,000
Ohio Power Co [Member] | Carrying Amount in AEGCo's Accounts Payable [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	16,822,000			16,822,000			22,139,000
Maximum Exposure	16,822,000			16,822,000			22,139,000
Public Service Co of Oklahoma [Member]
Basic and Diluted EPS Calculations
Earnings Attributable to AEP Common Shareholders	35,211,000		31,511,000	47,859,000		46,851,000
Amounts Attributable to AEP Common Shareholders
Net Income	35,211,000		31,511,000	47,859,000		46,851,000
Public Service Co of Oklahoma [Member] | Billings from AEPSC [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	21,301,000		21,130,000	38,897,000		40,548,000
Public Service Co of Oklahoma [Member] | Carrying Amount in AEPSC's Accounts Payable [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	8,067,000			8,067,000			9,280,000
Maximum Exposure	8,067,000			8,067,000			9,280,000
Southwestern Electric Power Co [Member]
Basic and Diluted EPS Calculations
Earnings Attributable to AEP Common Shareholders	53,841,000		49,978,000	89,153,000		78,666,000
Amounts Attributable to AEP Common Shareholders
Net Income	53,841,000		49,978,000	89,153,000		78,666,000
Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	36,000,000		30,000,000	91,000,000		64,000,000
Southwestern Electric Power Co [Member] | Dolet Hills Lignite Co, LLC [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	20,000,000		15,000,000	34,000,000		29,000,000
Percentage of VIE Sales of Lignite Produced				50.00%
Percentage of DHLC's Debt Guaranteed by Each SWEPCo and CLECO				50.00%
Percentage of Management Fee Received by SWEPCo from DHLC				100.00%
Southwestern Electric Power Co [Member] | Billings from AEPSC [Member]
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Billings from VIE	33,246,000		31,560,000	59,966,000		61,393,000
Southwestern Electric Power Co [Member] | Carrying Amount in AEPSC's Accounts Payable [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	12,302,000			12,302,000			14,699,000
Maximum Exposure	12,302,000			12,302,000			14,699,000
Southwestern Electric Power Co [Member] | Capital Contribution from Parent [Member] | Dolet Hills Lignite Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	7,643,000			7,643,000			7,643,000
Maximum Exposure	7,643,000			7,643,000			7,643,000
Southwestern Electric Power Co [Member] | Retained Earnings [Member] | Dolet Hills Lignite Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	1,163,000			1,163,000			1,120,000
Maximum Exposure	1,163,000			1,163,000			1,120,000
Southwestern Electric Power Co [Member] | SWEPCo's Guarantee of Debt [Member] | Dolet Hills Lignite Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	0			0			0
Maximum Exposure	56,706,000			56,706,000			52,310,000
Southwestern Electric Power Co [Member] | Total Investment [Member] | Dolet Hills Lignite Co, LLC [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract]
As Reported on the Consolidated Balance Sheet	8,806,000			8,806,000			8,763,000
Maximum Exposure	65,512,000			65,512,000			61,073,000
Current Liabilities [Member] | Sabine Mining Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	42,000,000			42,000,000			68,000,000
Current Liabilities [Member] | DCC Fuel [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	127,000,000			127,000,000			103,000,000
Current Liabilities [Member] | Protected Cell of Energy Insurance Services, Inc. [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	43,000,000			43,000,000			40,000,000
Current Liabilities [Member] | AEP Credit, Inc. [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	851,000,000			851,000,000			864,000,000
Current Liabilities [Member] | AEP Texas Central Transition Funding Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	303,000,000			303,000,000			229,000,000
Current Liabilities [Member] | Indiana Michigan Power Co [Member] | DCC Fuel [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	126,595,000			126,595,000			102,946,000
Current Liabilities [Member] | Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	42,028,000			42,028,000			67,779,000
Noncurrent Liabilities [Member] | Sabine Mining Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	252,000,000			252,000,000			176,000,000
Noncurrent Liabilities [Member] | DCC Fuel [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	404,000,000			404,000,000			321,000,000
Noncurrent Liabilities [Member] | Protected Cell of Energy Insurance Services, Inc. [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	67,000,000			67,000,000			71,000,000
Noncurrent Liabilities [Member] | AEP Credit, Inc. [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	1,000,000			1,000,000			1,000,000
Noncurrent Liabilities [Member] | AEP Texas Central Transition Funding Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	2,207,000,000			2,207,000,000			1,557,000,000
Noncurrent Liabilities [Member] | Indiana Michigan Power Co [Member] | DCC Fuel [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	404,060,000			404,060,000			321,345,000
Noncurrent Liabilities [Member] | Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	251,532,000			251,532,000			176,163,000
Equity [Member] | Sabine Mining Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	0			0			0
Equity [Member] | DCC Fuel [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	0			0			0
Equity [Member] | Protected Cell of Energy Insurance Services, Inc. [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	20,000,000			20,000,000			16,000,000
Equity [Member] | AEP Credit, Inc. [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	46,000,000			46,000,000			46,000,000
Equity [Member] | AEP Texas Central Transition Funding Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	18,000,000			18,000,000			14,000,000
Equity [Member] | Indiana Michigan Power Co [Member] | DCC Fuel [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	0			0			0
Equity [Member] | Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	340,000			340,000			391,000
Total Liabilities and Equity [Member] | Sabine Mining Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	294,000,000			294,000,000			244,000,000
Total Liabilities and Equity [Member] | DCC Fuel [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	531,000,000			531,000,000			424,000,000
Total Liabilities and Equity [Member] | Protected Cell of Energy Insurance Services, Inc. [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	130,000,000			130,000,000			127,000,000
Total Liabilities and Equity [Member] | AEP Credit, Inc. [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	898,000,000			898,000,000			911,000,000
Total Liabilities and Equity [Member] | AEP Texas Central Transition Funding Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	2,528,000,000			2,528,000,000			1,800,000,000
Total Liabilities and Equity [Member] | Indiana Michigan Power Co [Member] | DCC Fuel [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	530,655,000			530,655,000			424,291,000
Total Liabilities and Equity [Member] | Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
LIABILITIES AND EQUITY
Liabilities and Equity	293,900,000			293,900,000			244,333,000
Current Assets [Member] | Sabine Mining Co [Member]
ASSETS
Assets	67,000,000			67,000,000			48,000,000
Current Assets [Member] | DCC Fuel [Member]
ASSETS
Assets	147,000,000			147,000,000			118,000,000
Current Assets [Member] | Protected Cell of Energy Insurance Services, Inc. [Member]
ASSETS
Assets	125,000,000			125,000,000			121,000,000
Current Assets [Member] | AEP Credit, Inc. [Member]
ASSETS
Assets	897,000,000			897,000,000			910,000,000
Current Assets [Member] | AEP Texas Central Transition Funding Co [Member]
ASSETS
Assets	235,000,000			235,000,000			220,000,000
Current Assets [Member] | Indiana Michigan Power Co [Member] | DCC Fuel [Member]
ASSETS
Assets	146,857,000			146,857,000			118,144,000
Current Assets [Member] | Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
ASSETS
Assets	66,966,000			66,966,000			48,044,000
Net Property Plant and Equipment [Member] | Sabine Mining Co [Member]
ASSETS
Assets	170,000,000			170,000,000			154,000,000
Net Property Plant and Equipment [Member] | DCC Fuel [Member]
ASSETS
Assets	241,000,000			241,000,000			188,000,000
Net Property Plant and Equipment [Member] | Protected Cell of Energy Insurance Services, Inc. [Member]
ASSETS
Assets	0			0			0
Net Property Plant and Equipment [Member] | AEP Credit, Inc. [Member]
ASSETS
Assets	0			0			0
Net Property Plant and Equipment [Member] | AEP Texas Central Transition Funding Co [Member]
ASSETS
Assets	0			0			0
Net Property Plant and Equipment [Member] | Indiana Michigan Power Co [Member] | DCC Fuel [Member]
ASSETS
Assets	240,961,000			240,961,000			188,375,000
Net Property Plant and Equipment [Member] | Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
ASSETS
Assets	169,929,000			169,929,000			153,715,000
Other Non Current Assets [Member] | Sabine Mining Co [Member]
ASSETS
Assets	57,000,000			57,000,000			42,000,000
Other Non Current Assets [Member] | DCC Fuel [Member]
ASSETS
Assets	143,000,000			143,000,000			118,000,000
Other Non Current Assets [Member] | Protected Cell of Energy Insurance Services, Inc. [Member]
ASSETS
Assets	5,000,000			5,000,000			6,000,000
Other Non Current Assets [Member] | AEP Credit, Inc. [Member]
ASSETS
Assets	1,000,000			1,000,000			1,000,000
Other Non Current Assets [Member] | AEP Texas Central Transition Funding Co [Member]
ASSETS
Assets	2,293,000,000	[1]		2,293,000,000	[1]		1,580,000,000
Organization and Summary of Significant Accounting Policies (Textuals) [Abstract]
Intercompany Item Eliminated in Consolidation	92,000,000			92,000,000
Other Non Current Assets [Member] | Indiana Michigan Power Co [Member] | DCC Fuel [Member]
ASSETS
Assets	142,837,000			142,837,000			117,772,000
Other Non Current Assets [Member] | Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
ASSETS
Assets	57,005,000			57,005,000			42,574,000
Total Assets [Member] | Sabine Mining Co [Member]
ASSETS
Assets	294,000,000			294,000,000			244,000,000
Total Assets [Member] | DCC Fuel [Member]
ASSETS
Assets	531,000,000			531,000,000			424,000,000
Total Assets [Member] | Protected Cell of Energy Insurance Services, Inc. [Member]
ASSETS
Assets	130,000,000			130,000,000			127,000,000
Total Assets [Member] | AEP Credit, Inc. [Member]
ASSETS
Assets	898,000,000			898,000,000			911,000,000
Total Assets [Member] | AEP Texas Central Transition Funding Co [Member]
ASSETS
Assets	2,528,000,000			2,528,000,000			1,800,000,000
Total Assets [Member] | Indiana Michigan Power Co [Member] | DCC Fuel [Member]
ASSETS
Assets	530,655,000			530,655,000			424,291,000
Total Assets [Member] | Southwestern Electric Power Co [Member] | Sabine Mining Co [Member]
ASSETS
Assets	293,900,000			293,900,000			244,333,000
Stock Options [Member]
Weighted Average Dilutive Effect of:
Weighted Average Dilutive Effect of Shares	100,000		100,000	100,000		100,000
Dilutive Securities, Effect on Basic Earnings Per Share	0		0	0		0
Restricted Stock Units [Member]
Weighted Average Dilutive Effect of:
Weighted Average Dilutive Effect of Shares	300,000		200,000	300,000		200,000
Dilutive Securities, Effect on Basic Earnings Per Share	$ 0		$ 0	$ 0		$ 0

[1] Includes an intercompany item eliminated in consolidation of $92 million.