Financing Activities (Details) - USD ($)		1 Months Ended		12 Months Ended
		Feb. 24, 2022	Jan. 31, 2022	Dec. 31, 2021		Dec. 31, 2020		Dec. 31, 2019
Shares of Company
Beginning Balance, Shares			524,416,175	516,808,354		514,373,631		513,450,036
Issued				7,607,821		2,434,723		923,595
Ending Balance, Shares				524,416,175		516,808,354		514,373,631
Treasury Stock, Shares, Beginning Balance			20,204,160	20,204,160		20,204,160		20,204,160
Treasury Stock, Shares, Ending Balance				20,204,160		20,204,160		20,204,160
Long-term Debt
Senior Unsecured Notes				$ 27,497,300,000		$ 25,116,100,000
Pollution Control Bonds	[1]			1,804,500,000		1,936,700,000
Notes Payable	[2]			211,300,000		239,100,000
Securitization Bonds				603,500,000		716,400,000
Spent Nuclear Fuel Obligation	[3]			281,300,000		281,200,000
Junior Subordinated Notes	[4]			2,373,000,000		1,624,100,000
Other Long-term Debt				683,600,000		1,158,900,000
Total Long-term Debt Outstanding				33,454,500,000	[5],[6],[7]	31,072,500,000		$ 26,725,500,000
Outstanding Long-term Debt
Principal Amount, 2021				2,153,800,000
Principal Amount, 2022	[8]			2,629,900,000
Principal Amount, 2023	[9]			1,462,200,000
Principal Amount, 2024				1,762,400,000
Principal Amount, 2025				1,497,900,000
Principal Amount, After 2025				24,246,700,000
Principal Amount, Total				33,752,900,000
Unamortized Discount, Net and Debt Issuance Costs				(298,400,000)
Total Long-term Debt Outstanding				33,454,500,000	[5],[6],[7]	31,072,500,000		$ 26,725,500,000
Short-term Debt
Securitized Debt for Receivables	[10]			750,000,000.0		592,000,000.0
Commercial Paper				1,364,000,000		1,852,300,000
Notes Payable				0		35,000,000.0
Total Short-term Debt				$ 2,614,000,000		$ 2,479,300,000
Securitized Debt for Receivables	[10],[11]			0.19%		0.85%
Other Short-term Borrowings				$ 500,000,000.0		$ 0
Comparative Accounts Receivable Information
Effective Interest Rates on Securitization of Accounts Receivable				0.19%		0.85%		2.42%
Net Uncollectible Accounts Receivable Written Off				$ 26,500,000		$ 15,300,000		$ 26,600,000
Customer Accounts Receivable Managed Portfolio
Accounts Receivable Retained Interest and Pledged as Collateral Less Uncollectible Accounts				995,200,000		958,400,000
Total Principal Outstanding				750,000,000.0		592,000,000.0
Delinquent Securitized Accounts Receivable				57,900,000		62,300,000
Bad Debt Reserves Related to Securitized Sale of Accounts Receivable				42,800,000		60,000,000.0
Unbilled Receivables Related to Securitization, Sale of Accounts Receivable				307,100,000		296,800,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				16,792,000,000		14,918,500,000		15,561,400,000
Financing Activities (Textuals)
Repayments of Long-term Debt				2,989,300,000		1,339,800,000		1,220,800,000
Proceeds from Issuance of Long-term Debt				6,486,300,000		5,626,100,000		4,536,600,000
Forward Equity Purchase Contracts Included in Current and Noncurrent Liabilities as of December 31,				$ 47,800,000		(86,200,000)		(7,600,000)
Maximum Percentage Debt to Capitalization				67.50%
Restricted Net Assets				$ 15,500,000,000
Dividend Restrictions	[12]			2,655,200,000
Retained Earnings Available to Pay Dividends				8,200,000,000
Dividends Paid on Common Stock				(1,519,500,000)		(1,424,900,000)		(1,350,000,000)
Credit Facilities, Total				$ 5,000,000,000
Weighted Average Interest Rate of Commercial Paper Outstanding During Year				0.24%
Maximum Amount of Commercial Paper Outstanding				$ 2,500,000,000
Maximum Value of Shares to be Issued Under ATM Program				$ 1,000,000,000
Maximum Percentage Paid to Selling Agents				2.00%
Issuance of Common Stock, Net				$ 600,500,000		155,000,000.0		65,300,000
Commitment From Bank Conduits to Finance Receivables (One) [Domain]				125,000,000
Commitment from Bank Conduits to Finance Receivables Two				625,000,000
Total Commitment From Bank Conduits To Finance Receivables				750,000,000
Liabilities Held for Sale				1,880,900,000		0
Kentucky Power Co [Member]
Financing Activities (Textuals)
Disposal Group, Including Discontinued Operation, Liabilities				$ 1,100,000,000
Equity Distribution Agreement
Shares of Company
Issued				5,701,825
Financing Activities (Textuals)
Issuance of Common Stock, Net				$ 484,000,000
2019 Equity Units [Member]
Financing Activities (Textuals)
Equity Units Issued				16,100,000
Per Unit Conversion for Equity Units				$ 50
Net Equity Units Issuance Proceeds				785,000,000
Principal Amounts of Junior Subordinated Debt				$ 1,000
Forward Equity Purchase Contract Date				2022
Forward Equity Purchase Contracts Included in Current and Noncurrent Liabilities as of December 31,								47,300,000
Maximum Shares Issued Under Equity Units Conversion				9,701,860
Corporate unit ownership share of an equity unit				5.00%
2020 Equity Units [Member]
Financing Activities (Textuals)
Equity Units Issued				17,000,000
Per Unit Conversion for Equity Units				$ 50
Net Equity Units Issuance Proceeds				833,000,000
Principal Amounts of Junior Subordinated Debt				$ 1,000
Forward Equity Purchase Contract Date				2023
Equity Units Annual Distribution Rate				6.125%
Forward Equity Contract Payment Rate				4.825%
Forward Equity Purchase Contracts Included in Current and Noncurrent Liabilities as of December 31,				$ 0		$ 110,600,000
Maximum Shares Issued Under Equity Units Conversion				10,205,100
Corporate unit ownership share of an equity unit				5.00%
Minimum [Member] | 2019 Equity Units [Member]
Financing Activities (Textuals)
AEP Share Price for Equity Unit Conversion				$ 82.98
Shares Per Equity Unit				0.5021
Minimum [Member] | 2020 Equity Units [Member]
Financing Activities (Textuals)
AEP Share Price for Equity Unit Conversion				$ 83.29
Shares Per Equity Unit				0.5003
Maximum [Member] | 2019 Equity Units [Member]
Financing Activities (Textuals)
AEP Share Price for Equity Unit Conversion				$ 99.58
Shares Per Equity Unit				0.6026
Maximum [Member] | 2020 Equity Units [Member]
Financing Activities (Textuals)
AEP Share Price for Equity Unit Conversion				$ 99.95
Shares Per Equity Unit				0.6003
Kentucky Transmission Company
Financing Activities (Textuals)
Liabilities Held for Sale				$ 1,000,000
Commercial Paper [Member]
Short-term Debt
Debt, Weighted Average Interest Rate	[11]			0.34%		0.29%
Loans Payable [Member]
Short-term Debt
Debt, Weighted Average Interest Rate	[11]			0.00%		2.55%
364 Day Term Loan
Short-term Debt
Debt, Weighted Average Interest Rate				0.81%		0.00%
AEP Texas Inc. [Member]
Long-term Debt
Senior Unsecured Notes				$ 4,135,500,000		$ 3,687,600,000
Pollution Control Bonds				439,900,000		439,700,000
Securitization Bonds				404,700,000		492,600,000
Other Long-term Debt				200,700,000		200,500,000
Total Long-term Debt Outstanding				5,180,800,000		4,820,400,000
Outstanding Long-term Debt
Principal Amount, 2021				716,000,000.0
Principal Amount, 2022				278,500,000
Principal Amount, 2023				96,000,000.0
Principal Amount, 2024				324,500,000
Principal Amount, 2025				75,000,000.0
Principal Amount, After 2025				3,732,000,000
Principal Amount, Total				5,222,000,000
Unamortized Discount, Net and Debt Issuance Costs				(41,200,000)
Total Long-term Debt Outstanding				5,180,800,000		4,820,400,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				1,587,700,000		1,528,000,000		1,551,600,000
Financing Activities (Textuals)
Repayments of Long-term Debt				88,700,000		392,100,000		401,800,000
Proceeds from Issuance of Long-term Debt				$ 444,200,000		652,700,000		$ 1,070,400,000
Maximum Percentage Debt to Capitalization				67.50%
Dividend Restrictions				$ 791,800,000
AEP Texas Inc. [Member] | Utility [Member]
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Borrowings from Money Pool				355,500,000		320,400,000
Maximum Loans to Money Pool				104,700,000		313,400,000
Average Borrowings from Money Pool				172,500,000		132,000,000.0
Average Loans to Money Pool				40,000,000.0		139,000,000.0
Net Loans (Borrowings) to/from Money Pool				(26,900,000)		(67,100,000)
Authorized Short Term Borrowing Limit				$ 500,000,000.0		$ 500,000,000.0
Maximum and Minimum Interest Rates
Maximum Interest Rate				0.48%		2.70%		3.43%
Minimum Interest Rate				0.02%		0.27%		1.77%
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Borrowed				0.33%		1.51%		2.63%
Average Interest Rate For Funds Loaned				0.26%		0.81%		2.03%
AEP Texas Inc. [Member] | Nonutility [Member]
Maximum Interest Rate For Funds Loaned				0.58%		2.70%		3.02%
Minimum Interest Rate for Funds Loaned				0.21%		0.27%		1.91%
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Loans to Money Pool				$ 7,100,000		$ 7,500,000
Average Loans to Money Pool				6,900,000		7,100,000
Net Loans (Borrowings) to/from Money Pool				$ 6,900,000		$ 7,100,000
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Loaned				0.37%		1.18%		2.56%
AEP Transmission Co [Member]
Long-term Debt
Senior Unsecured Notes				$ 4,343,900,000		$ 3,948,500,000
Total Long-term Debt Outstanding				4,343,900,000		3,948,500,000		$ 3,427,300,000
Outstanding Long-term Debt
Principal Amount, 2021				104,000,000.0
Principal Amount, 2022				60,000,000.0
Principal Amount, 2023				95,000,000.0
Principal Amount, 2024				90,000,000.0
Principal Amount, 2025				425,000,000.0
Principal Amount, After 2025				3,616,000,000
Principal Amount, Total				4,390,000,000
Unamortized Discount, Net and Debt Issuance Costs				(46,100,000)
Total Long-term Debt Outstanding				4,343,900,000		3,948,500,000		3,427,300,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				1,410,900,000		1,232,700,000		1,042,100,000
Financing Activities (Textuals)
Repayments of Long-term Debt				50,000,000.0		0		85,000,000.0
Proceeds from Issuance of Long-term Debt				443,700,000		519,500,000		$ 688,000,000.0
Sub-Limit of Secured Debt				$ 50,000,000
Maximum Percentage of Consolidated Tangible Net Assets				10.00%
Tangible Capital to Tangible Assets				0.011
Maximum Percentage Debt to Capitalization				67.50%
Dividend Restrictions				$ 0
Liabilities Held for Sale				27,600,000		0
AEP Transmission Co [Member] | Utility [Member]
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Borrowings from Money Pool				444,900,000		358,400,000
Maximum Loans to Money Pool				117,300,000		259,700,000
Average Borrowings from Money Pool				189,100,000		116,300,000
Average Loans to Money Pool				29,700,000		55,000,000.0
Net Loans (Borrowings) to/from Money Pool				(108,000,000.0)	[13]	(155,400,000)
Authorized Short Term Borrowing Limit	[14]			$ 820,000,000.0		$ 820,000,000.0
Maximum and Minimum Interest Rates
Maximum Interest Rate				0.48%		2.70%		3.43%
Minimum Interest Rate				0.02%		0.27%		1.77%
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Borrowed				0.32%		1.29%		2.64%
Average Interest Rate For Funds Loaned				0.10%		1.99%		2.41%
AEP Transmission Co [Member] | Direct Borrowing [Member]
Maximum Interest Rate for Funds Borrowed				0.86%		2.70%		3.02%
Minimum Interest Rate For Funds Borrowed				0.25%		0.27%		1.91%
Maximum Interest Rate For Funds Loaned				0.86%		2.70%		3.02%
Minimum Interest Rate for Funds Loaned				0.25%		0.27%		1.91%
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Borrowings from Money Pool				$ 14,600,000		$ 1,400,000
Maximum Loans to Money Pool				224,200,000		215,300,000
Average Borrowings from Money Pool				1,800,000		1,300,000
Average Loans to Money Pool				118,000,000.0		132,600,000
Borrowings from Parent				1,500,000		1,200,000
Loans to Parent				12,700,000		109,000,000.0
Authorized Short Term Borrowing Limit	[15]			$ 50,000,000.0		$ 50,000,000.0
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Borrowed				0.38%		1.20%		2.55%
Average Interest Rate For Funds Loaned				0.35%		1.13%		2.51%
Appalachian Power Co [Member]
Long-term Debt
Senior Unsecured Notes				$ 4,083,700,000		$ 3,937,200,000
Pollution Control Bonds	[1]			529,500,000		546,300,000
Securitization Bonds				198,800,000		223,800,000
Other Long-term Debt				126,900,000		126,800,000
Total Long-term Debt Outstanding				4,938,900,000		4,834,100,000
Outstanding Long-term Debt
Principal Amount, 2021				480,700,000
Principal Amount, 2022				26,600,000
Principal Amount, 2023				113,500,000
Principal Amount, 2024				443,900,000
Principal Amount, 2025				30,900,000
Principal Amount, After 2025				3,887,400,000
Principal Amount, Total				4,983,000,000
Unamortized Discount, Net and Debt Issuance Costs				(44,100,000)
Total Long-term Debt Outstanding				4,938,900,000		4,834,100,000
Accounts Receivable and Accrued Unbilled Revenue
Accounts Receivable and Accrued Unbilled Revenues				153,100,000		136,000,000.0
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				3,092,900,000		2,809,200,000		$ 2,911,100,000
Proceeds on Sale of Receivables to AEP Credit
Proceeds from Sale of Receivables to AEP Credit				1,324,100,000		1,272,900,000		1,310,300,000
Financing Activities (Textuals)
Repayments of Long-term Debt				393,000,000.0		140,300,000		180,500,000
Proceeds from Issuance of Long-term Debt				$ 494,000,000.0		606,900,000		$ 478,200,000
Maximum Percentage Debt to Capitalization				67.50%
Dividend Restrictions				$ 313,400,000
Appalachian Power Co [Member] | Utility [Member]
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Borrowings from Money Pool				199,300,000		434,300,000
Maximum Loans to Money Pool				616,900,000		189,000,000.0
Average Borrowings from Money Pool				87,500,000		242,800,000
Average Loans to Money Pool				118,300,000		76,300,000
Net Loans (Borrowings) to/from Money Pool				(178,500,000)		2,800,000
Authorized Short Term Borrowing Limit				$ 500,000,000.0		$ 500,000,000.0
Maximum and Minimum Interest Rates
Maximum Interest Rate				0.48%		2.70%		3.43%
Minimum Interest Rate				0.02%		0.27%		1.77%
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Borrowed				0.41%		2.12%		2.45%
Average Interest Rate For Funds Loaned				0.25%		0.85%		2.66%
Indiana Michigan Power Co [Member]
Long-term Debt
Senior Unsecured Notes				$ 2,595,500,000		$ 2,152,200,000
Pollution Control Bonds	[1]			188,700,000		240,500,000
Notes Payable	[2]			122,200,000		146,700,000
Spent Nuclear Fuel Obligation	[3]			281,300,000		281,200,000
Other Long-term Debt				7,300,000		209,300,000
Total Long-term Debt Outstanding				3,195,000,000		3,029,900,000
Outstanding Long-term Debt
Principal Amount, 2021				67,000,000.0
Principal Amount, 2022				289,800,000
Principal Amount, 2023				16,800,000
Principal Amount, 2024				195,900,000
Principal Amount, 2025				0
Principal Amount, After 2025				2,656,300,000
Principal Amount, Total				3,225,800,000
Unamortized Discount, Net and Debt Issuance Costs				(30,800,000)
Total Long-term Debt Outstanding				3,195,000,000		3,029,900,000
Accounts Receivable and Accrued Unbilled Revenue
Accounts Receivable and Accrued Unbilled Revenues				156,900,000		170,500,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				2,330,700,000		2,236,000,000		$ 2,308,100,000
Proceeds on Sale of Receivables to AEP Credit
Proceeds from Sale of Receivables to AEP Credit				1,927,000,000		1,891,800,000		1,824,200,000
Financing Activities (Textuals)
Repayments of Long-term Debt				383,500,000		93,200,000		117,100,000
Proceeds from Issuance of Long-term Debt				$ 546,700,000		69,500,000		$ 123,300,000
Maximum Percentage Debt to Capitalization				67.50%
Dividend Restrictions				$ 648,500,000
Indiana Michigan Power Co [Member] | Utility [Member]
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Borrowings from Money Pool				166,500,000		218,600,000
Maximum Loans to Money Pool				368,200,000		13,400,000
Average Borrowings from Money Pool				110,400,000		114,500,000
Average Loans to Money Pool				67,700,000		13,300,000
Net Loans (Borrowings) to/from Money Pool				(71,800,000)		(89,700,000)
Authorized Short Term Borrowing Limit				$ 500,000,000.0		$ 500,000,000.0
Maximum and Minimum Interest Rates
Maximum Interest Rate				0.48%		2.70%		3.43%
Minimum Interest Rate				0.02%		0.27%		1.77%
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Borrowed				0.33%		1.07%		2.34%
Average Interest Rate For Funds Loaned				0.23%		1.18%		2.60%
Ohio Power Co [Member]
Long-term Debt
Senior Unsecured Notes				$ 2,967,800,000		$ 2,429,400,000
Other Long-term Debt				700,000		800,000
Total Long-term Debt Outstanding				2,968,500,000		2,430,200,000
Outstanding Long-term Debt
Principal Amount, 2021				100,000
Principal Amount, 2022				100,000
Principal Amount, 2023				100,000
Principal Amount, 2024				100,000
Principal Amount, 2025				100,000
Principal Amount, After 2025				3,000,200,000
Principal Amount, Total				3,000,700,000
Unamortized Discount, Net and Debt Issuance Costs				(32,200,000)
Total Long-term Debt Outstanding				2,968,500,000		2,430,200,000
Accounts Receivable and Accrued Unbilled Revenue
Accounts Receivable and Accrued Unbilled Revenues				392,700,000		398,800,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				2,837,500,000		2,665,000,000		$ 2,748,800,000
Proceeds on Sale of Receivables to AEP Credit
Proceeds from Sale of Receivables to AEP Credit				2,458,500,000		2,366,200,000		2,293,600,000
Financing Activities (Textuals)
Repayments of Long-term Debt				500,100,000		100,000		80,300,000
Proceeds from Issuance of Long-term Debt				1,037,100,000		347,000,000.0		$ 444,300,000
Dividend Restrictions				0
Ohio Power Co [Member] | Utility [Member]
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Borrowings from Money Pool				259,200,000		353,900,000
Maximum Loans to Money Pool				622,900,000		32,800,000
Average Borrowings from Money Pool				61,600,000		182,400,000
Average Loans to Money Pool				127,200,000		25,200,000
Net Loans (Borrowings) to/from Money Pool				42,000,000.0		(259,200,000)
Authorized Short Term Borrowing Limit				$ 500,000,000.0		$ 500,000,000.0
Maximum and Minimum Interest Rates
Maximum Interest Rate				0.48%		2.70%		3.43%
Minimum Interest Rate				0.02%		0.27%		1.77%
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Borrowed				0.27%		0.99%		2.67%
Average Interest Rate For Funds Loaned				0.14%		2.06%		2.68%
Public Service Co Of Oklahoma [Member]
Shares of Company
Beginning Balance, Shares			10,482,000	10,482,000
Ending Balance, Shares				10,482,000		10,482,000
Long-term Debt
Senior Unsecured Notes				$ 1,785,500,000		$ 1,246,300,000
Other Long-term Debt				128,000,000.0		127,500,000
Total Long-term Debt Outstanding				1,913,500,000		1,373,800,000
Outstanding Long-term Debt
Principal Amount, 2021				125,500,000
Principal Amount, 2022				500,000
Principal Amount, 2023				600,000
Principal Amount, 2024				125,600,000
Principal Amount, 2025				50,600,000
Principal Amount, After 2025				1,625,300,000
Principal Amount, Total				1,928,100,000
Unamortized Discount, Net and Debt Issuance Costs				(14,600,000)
Total Long-term Debt Outstanding				1,913,500,000		1,373,800,000
Accounts Receivable and Accrued Unbilled Revenue
Accounts Receivable and Accrued Unbilled Revenues				114,500,000		85,000,000.0
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				1,474,300,000		1,263,900,000		$ 1,512,800,000
Proceeds on Sale of Receivables to AEP Credit
Proceeds from Sale of Receivables to AEP Credit				1,406,400,000		1,221,000,000		1,442,500,000
Financing Activities (Textuals)
Repayments of Long-term Debt				750,500,000		13,200,000		250,500,000
Proceeds from Issuance of Long-term Debt				$ 1,290,000,000		0		$ 349,500,000
Maximum Percentage Debt to Capitalization				67.50%
Dividend Restrictions				$ 0
Public Service Co Of Oklahoma [Member] | Utility [Member]
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Borrowings from Money Pool				267,700,000		155,400,000
Maximum Loans to Money Pool				747,300,000		57,100,000
Average Borrowings from Money Pool				134,000,000.0		72,300,000
Average Loans to Money Pool				113,100,000		28,400,000
Net Loans (Borrowings) to/from Money Pool				(72,300,000)		(155,400,000)
Authorized Short Term Borrowing Limit				$ 400,000,000.0		$ 300,000,000.0
Maximum and Minimum Interest Rates
Maximum Interest Rate				0.48%		2.70%		3.43%
Minimum Interest Rate				0.02%		0.27%		1.77%
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Borrowed				0.34%		0.92%		2.85%
Average Interest Rate For Funds Loaned				0.07%		1.95%		2.27%
Southwestern Electric Power Co [Member]
Long-term Debt
Senior Unsecured Notes				$ 3,295,100,000		$ 2,430,800,000
Notes Payable	[2]			59,100,000		62,400,000
Other Long-term Debt				41,000,000.0		143,200,000
Total Long-term Debt Outstanding				3,395,200,000		2,636,400,000
Outstanding Long-term Debt
Principal Amount, 2021				6,200,000
Principal Amount, 2022				6,200,000
Principal Amount, 2023				31,200,000
Principal Amount, 2024				6,200,000
Principal Amount, 2025				906,200,000
Principal Amount, After 2025				2,469,300,000
Principal Amount, Total				3,425,300,000
Unamortized Discount, Net and Debt Issuance Costs				(30,100,000)
Total Long-term Debt Outstanding				3,395,200,000		2,636,400,000
Short-term Debt
Notes Payable				0		35,000,000.0
Accounts Receivable and Accrued Unbilled Revenue
Accounts Receivable and Accrued Unbilled Revenues				153,000,000.0		158,600,000
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				2,126,000,000		1,735,300,000		$ 1,799,200,000
Proceeds on Sale of Receivables to AEP Credit
Proceeds from Sale of Receivables to AEP Credit				1,636,100,000		1,593,800,000		1,618,500,000
Financing Activities (Textuals)
Repayments of Long-term Debt				381,200,000		21,200,000		59,700,000
Proceeds from Issuance of Long-term Debt				$ 1,137,600,000		0		0
Maximum Percentage Debt to Capitalization				67.50%
Dividend Restrictions				$ 577,900,000
Dividends Paid on Common Stock				(4,800,000)		(1,900,000)		$ (3,300,000)
Southwestern Electric Power Co [Member] | Utility [Member]
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Borrowings from Money Pool				280,300,000		178,900,000
Maximum Loans to Money Pool				561,900,000		0
Average Borrowings from Money Pool				142,400,000		113,000,000.0
Average Loans to Money Pool				287,400,000		0
Net Loans (Borrowings) to/from Money Pool				153,800,000		(124,600,000)
Authorized Short Term Borrowing Limit				$ 400,000,000.0		$ 350,000,000.0
Maximum and Minimum Interest Rates
Maximum Interest Rate				0.48%		2.70%		3.43%
Minimum Interest Rate				0.02%		0.27%		1.77%
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Borrowed				0.26%		1.27%		2.72%
Average Interest Rate For Funds Loaned				0.18%		0.00%		2.22%
Southwestern Electric Power Co [Member] | Nonutility [Member]
Maximum Interest Rate For Funds Loaned				0.58%		2.70%		3.02%
Minimum Interest Rate for Funds Loaned				0.21%		0.27%		1.91%
Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits
Maximum Loans to Money Pool				$ 2,100,000		$ 2,100,000
Average Loans to Money Pool				2,100,000		2,100,000
Net Loans (Borrowings) to/from Money Pool				$ 2,100,000		$ 2,100,000
Average Interest Rates for Funds Borrowed from and Loaned to Money Pool
Average Interest Rate For Funds Loaned				0.37%		1.18%		2.55%
Southwestern Electric Power Co [Member] | Loans Payable [Member]
Short-term Debt
Debt, Weighted Average Interest Rate	[11]			0.00%		2.55%
Senior Notes [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2051
Weighted Average Interest Rate				3.69%
Senior Notes [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				0.61%		0.70%
Senior Notes [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				7.00%		8.13%
Senior Notes [Member] | AEP Texas Inc. [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2022
Maturity Date High				2051
Weighted Average Interest Rate				3.67%
Senior Notes [Member] | AEP Texas Inc. [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				2.10%		2.10%
Senior Notes [Member] | AEP Texas Inc. [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				6.76%		6.76%
Senior Notes [Member] | AEP Transmission Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2051
Weighted Average Interest Rate				3.73%
Senior Notes [Member] | AEP Transmission Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				2.75%		3.10%
Senior Notes [Member] | AEP Transmission Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				5.52%		5.52%
Senior Notes [Member] | Appalachian Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2050
Weighted Average Interest Rate				4.70%
Senior Notes [Member] | Appalachian Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				2.70%		3.30%
Senior Notes [Member] | Appalachian Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				7.00%		7.00%
Senior Notes [Member] | Indiana Michigan Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2023
Maturity Date High				2051
Weighted Average Interest Rate				4.19%
Senior Notes [Member] | Indiana Michigan Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				3.20%		3.20%
Senior Notes [Member] | Indiana Michigan Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				6.05%		6.05%
Senior Notes [Member] | Ohio Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2051
Weighted Average Interest Rate				3.87%
Senior Notes [Member] | Ohio Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				1.63%		2.60%
Senior Notes [Member] | Ohio Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				6.60%		6.60%
Senior Notes [Member] | Public Service Co Of Oklahoma [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2051
Weighted Average Interest Rate				3.74%
Senior Notes [Member] | Public Service Co Of Oklahoma [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				2.20%		3.05%
Senior Notes [Member] | Public Service Co Of Oklahoma [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				6.63%		6.63%
Senior Notes [Member] | Southwestern Electric Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2022
Maturity Date High				2051
Weighted Average Interest Rate				3.57%
Senior Notes [Member] | Southwestern Electric Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				1.65%		2.75%
Senior Notes [Member] | Southwestern Electric Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				6.20%		6.20%
Pollution Control Bonds [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low	[16]			2021
Maturity Date High	[16]			2036
Weighted Average Interest Rate				2.40%
Pollution Control Bonds [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				0.19%		0.18%
Pollution Control Bonds [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				4.55%		4.63%
Pollution Control Bonds [Member] | AEP Texas Inc. [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low	[16]			2023
Maturity Date High	[16]			2030
Weighted Average Interest Rate				3.42%
Pollution Control Bonds [Member] | AEP Texas Inc. [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				0.90%		0.90%
Pollution Control Bonds [Member] | AEP Texas Inc. [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				4.55%		4.55%
Pollution Control Bonds [Member] | Appalachian Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low	[16]			2021
Maturity Date High	[16]			2036
Weighted Average Interest Rate				1.67%
Pollution Control Bonds [Member] | Appalachian Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				0.19%		0.19%
Pollution Control Bonds [Member] | Appalachian Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				2.75%		4.63%
Pollution Control Bonds [Member] | Indiana Michigan Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low	[16]			2021
Maturity Date High	[16]			2025
Weighted Average Interest Rate				2.49%
Pollution Control Bonds [Member] | Indiana Michigan Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				0.75%		0.18%
Pollution Control Bonds [Member] | Indiana Michigan Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				3.05%		3.05%
Notes Payable, Other Payables [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2032
Weighted Average Interest Rate				2.41%
Notes Payable, Other Payables [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				0.79%		0.84%
Notes Payable, Other Payables [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				6.37%		6.37%
Notes Payable, Other Payables [Member] | Indiana Michigan Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2025
Weighted Average Interest Rate				0.99%
Notes Payable, Other Payables [Member] | Indiana Michigan Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				0.79%		0.84%
Notes Payable, Other Payables [Member] | Indiana Michigan Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				1.24%		1.29%
Notes Payable, Other Payables [Member] | Indiana Michigan Power Co [Member] | Subsequent Event [Member]
Financing Activities (Textuals)
Repayments of Long-term Debt		$ 8,000,000	$ 8,000,000
Notes Payable, Other Payables [Member] | Southwestern Electric Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2024
Maturity Date High				2032
Weighted Average Interest Rate				5.34%
Notes Payable, Other Payables [Member] | Southwestern Electric Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				4.58%		4.58%
Notes Payable, Other Payables [Member] | Southwestern Electric Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				6.37%		6.37%
Securitization Bonds [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low	[17]			2023
Maturity Date High	[17]			2029
Weighted Average Interest Rate				2.84%
Securitization Bonds [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				2.01%		2.01%
Securitization Bonds [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				3.77%		3.77%
Securitization Bonds [Member] | AEP Texas Inc. [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low	[17]			2024
Maturity Date High	[17]			2029
Weighted Average Interest Rate				2.53%
Securitization Bonds [Member] | AEP Texas Inc. [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				2.06%		2.06%
Securitization Bonds [Member] | AEP Texas Inc. [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				2.84%		2.84%
Securitization Bonds [Member] | AEP Texas Inc. [Member] | Subsequent Event [Member]
Financing Activities (Textuals)
Repayments of Long-term Debt		11,000,000
Securitization Bonds [Member] | Appalachian Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low	[17]			2023
Maturity Date High	[17]			2028
Weighted Average Interest Rate				3.46%
Securitization Bonds [Member] | Appalachian Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				2.01%		2.01%
Securitization Bonds [Member] | Appalachian Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				3.77%		3.77%
Securitization Bonds [Member] | Appalachian Power Co [Member] | Subsequent Event [Member]
Financing Activities (Textuals)
Repayments of Long-term Debt		13,000,000
Junior Subordinated Notes [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2023
Maturity Date High				2027
Weighted Average Interest Rate				2.81%
Junior Subordinated Notes [Member] | 2019 Equity Units [Member]
Financing Activities (Textuals)
Proceeds from Issuance of Debt				$ 805,000,000
Junior Subordinated Notes [Member] | 2020 Equity Units [Member]
Financing Activities (Textuals)
Proceeds from Issuance of Debt				$ 850,000,000
Junior Subordinated Notes [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				1.30%		1.30%
Junior Subordinated Notes [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				3.88%		3.40%
Other Long Term Debt [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2059
Weighted Average Interest Rate				1.63%
Other Long Term Debt [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				0.91%		0.81%
Other Long Term Debt [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				13.72%		13.72%
Other Long Term Debt [Member] | AEP Texas Inc. [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2022
Maturity Date High				2059
Weighted Average Interest Rate				1.37%
Other Long Term Debt [Member] | AEP Texas Inc. [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				1.35%		1.40%
Other Long Term Debt [Member] | AEP Texas Inc. [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				4.50%		4.50%
Other Long Term Debt [Member] | Appalachian Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2022
Maturity Date High				2026
Weighted Average Interest Rate				1.42%
Other Long Term Debt [Member] | Appalachian Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				1.24%		1.32%
Other Long Term Debt [Member] | Appalachian Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				13.72%		13.72%
Other Long Term Debt [Member] | Indiana Michigan Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2025
Weighted Average Interest Rate				6.00%
Other Long Term Debt [Member] | Indiana Michigan Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				6.00%		1.28%
Other Long Term Debt [Member] | Indiana Michigan Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				6.00%		6.00%
Other Long Term Debt [Member] | Ohio Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2028
Maturity Date High				2028
Weighted Average Interest Rate				1.15%
Other Long Term Debt [Member] | Ohio Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				1.15%		1.15%
Other Long Term Debt [Member] | Ohio Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				1.15%		1.15%
Other Long Term Debt [Member] | Public Service Co Of Oklahoma [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2022
Maturity Date High				2027
Weighted Average Interest Rate				1.50%
Other Long Term Debt [Member] | Public Service Co Of Oklahoma [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				1.47%		1.42%
Other Long Term Debt [Member] | Public Service Co Of Oklahoma [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				3.00%		3.00%
Other Long Term Debt [Member] | Public Service Co Of Oklahoma [Member] | Subsequent Event [Member]
Financing Activities (Textuals)
Proceeds from Issuance of Long-term Debt		$ 500,000,000
Other Long Term Debt [Member] | Southwestern Electric Power Co [Member]
Long- term Debt by Type of Debt and Maturity
Maturity Date Low				2021
Maturity Date High				2035
Weighted Average Interest Rate				4.68%
Other Long Term Debt [Member] | Southwestern Electric Power Co [Member] | Minimum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				4.68%		2.25%
Other Long Term Debt [Member] | Southwestern Electric Power Co [Member] | Maximum [Member]
Long- term Debt by Type of Debt and Maturity
Interest Rate				4.68%		4.68%
Junior Subordinated Debt [Member] | 2019 Equity Units [Member]
Financing Activities (Textuals)
Debt Instrument, Interest Rate, Stated Percentage				3.40%
Junior Subordinated Debt [Member] | 2020 Equity Units [Member]
Financing Activities (Textuals)
Debt Instrument, Interest Rate, Stated Percentage				1.30%
Junior Subordinated Debt [Member] | Subsequent Event [Member] | 2019 Equity Units [Member]
Financing Activities (Textuals)
Debt Instrument, Interest Rate, Stated Percentage		2.031%
Servicing Contracts [Member] | Appalachian Power Co [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				$ 4,900,000		$ 5,200,000		$ 7,400,000
Servicing Contracts [Member] | Indiana Michigan Power Co [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				7,000,000.0		7,900,000		11,100,000
Servicing Contracts [Member] | Ohio Power Co [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				8,300,000		24,100,000		27,100,000
Servicing Contracts [Member] | Public Service Co Of Oklahoma [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				3,400,000		4,800,000		7,800,000
Servicing Contracts [Member] | Southwestern Electric Power Co [Member]
Fees Paid to AEP Credit for Customer Accounts Receivable Sold
Revenue from Contracts with Customers				5,400,000		6,700,000		10,200,000
Retained Earnings [Member]
Financing Activities (Textuals)
Forward Equity Purchase Contracts Included in Current and Noncurrent Liabilities as of December 31,				(1,100,000)
Dividends Paid on Common Stock				1,500,000,000		(1,400,000,000)		(1,300,000,000)
Additional Paid-in Capital [Member]
Financing Activities (Textuals)
Forward Equity Purchase Contracts Included in Current and Noncurrent Liabilities as of December 31,				32,600,000		$ (85,800,000)	[18]	$ (9,800,000)	[19]
Additional Paid-in Capital [Member] | 2019 Equity Units [Member]
Financing Activities (Textuals)
Forward Equity Purchase Contracts Included in Current and Noncurrent Liabilities as of December 31,				62,000,000
Additional Paid-in Capital [Member] | 2020 Equity Units [Member]
Financing Activities (Textuals)
Forward Equity Purchase Contracts Included in Current and Noncurrent Liabilities as of December 31,				$ 121,000,000

[1] For certain series of Pollution Control Bonds, interest rates are subject to periodic adjustment.  Certain series may be purchased on demand at periodic interest adjustment dates.  Letters of credit from banks and insurance policies support certain series. Consequently, these bonds have been classified for maturity purposes as Long-term Debt Due Within One Year - Nonaffiliated on the balance sheets.

[2] Notes payable represent outstanding promissory notes issued under term loan agreements and credit agreements with a number of banks and other financial institutions. At expiration, all notes then issued and outstanding are due and payable. Interest rates are both fixed and variable. Variable rates generally relate to specified short-term interest rates.

[3] Spent Nuclear Fuel Obligation consists of a liability along with accrued interest for disposal of SNF. See “Spent Nuclear Fuel Disposal” section of Note 6 for additional information.

[4] See “Equity Units” section below for additional information.

[5] 2021 amount excludes $1.1 billion of Total Long-term Debt Outstanding classified as Liabilities Held for Sale on the balance sheet. See “Disposition of KPCo and KTCo” section of Note 7 for additional information.

[6] Amount excludes $1.1 billion of Total Long-term Debt Outstanding classified as Liabilities Held for Sale on the balance sheet. See “Disposition of KPCo and KTCo” section of Note 7 for additional information

[7] The 2021 book value amount excludes Long-term Debt of $1.1 billion classified as Liabilities Held for Sale on the balance sheets. See “Disposition of KPCo and KTCo” section of Note 7 for additional information.

[8] Amount includes $850 million of Junior Subordinated Notes. See “Equity Units” section below for additional information.

[9] Amount includes $805 million of Junior Subordinated Notes. See “Equity Units” section below for additional information.

[10] Amount of securitized debt for receivables as accounted for under the “Transfers and Servicing” accounting guidance.

[11] Weighted-average rate.

[12] Includes the restrictions of consolidated and non-consolidated subsidiaries.

[13] Amount excludes $1 million of Advances from Affiliates classified as Liabilities Held for Sale on the AEP Transco balance sheet. See “Dispositions of KPCo and KTCo” section of Note 7 for additional information.

[14] Amount represents the combined authorized short-term borrowing limit the State Transcos have from FERC or state regulatory commissions.

[15] Amount represents the combined authorized short-term borrowing limit the State Transcos have from FERC or state regulatory commissions.

[16] Certain Pollution Control Bonds are subject to redemption earlier than the maturity date.

[17] Dates represent the scheduled final payment dates for the securitization bonds. The legal maturity date is one to two years later. These bonds have been classified for maturity and repayment purposes based on the scheduled final payment date.

[18] (c)    Includes $(121) million related to a forward equity purchase contract associated with the issuance of Equity Units. See “Equity Units” section of Note 14 for additional information.

[19] (b)    Includes $(62) million related to a forward equity purchase contract associated with the issuance of Equity Units. See “Equity Units” section of Note 14 for additional information.