Income Taxes (Details)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal Statutory Rate	21.00%	21.00%
State Income Tax, net of Federal Benefit	1.50%	2.30%
Tax Reform Excess ADIT Reversal	(6.60%)	(9.20%)
Production and Investment Tax Credits	(8.00%)	(5.50%)
Flow Through	0.30%	0.30%
AFUDC Equity	(0.90%)	(0.90%)
Parent Company Loss Benefit		0.00%
Discrete Tax Adjustments	(0.60%)	0.50%
Other	0.20%	0.10%
Effective Income Tax Rate	6.90%	8.60%
AEP Texas Inc. [Member]
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal Statutory Rate	21.00%	21.00%
State Income Tax, net of Federal Benefit	0.30%	1.40%
Tax Reform Excess ADIT Reversal	(2.00%)	(7.80%)
Production and Investment Tax Credits	(0.20%)	(0.30%)
Flow Through	0.30%	0.30%
AFUDC Equity	(0.90%)	(1.40%)
Parent Company Loss Benefit		0.00%
Discrete Tax Adjustments	0.00%	0.00%
Other	(0.10%)	0.10%
Effective Income Tax Rate	18.40%	13.30%
AEP Transmission Co [Member]
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal Statutory Rate	21.00%	21.00%
State Income Tax, net of Federal Benefit	2.60%	2.70%
Tax Reform Excess ADIT Reversal	0.30%	0.30%
Production and Investment Tax Credits	0.00%	0.00%
Flow Through	0.30%	0.20%
AFUDC Equity	(1.60%)	(1.70%)
Parent Company Loss Benefit		(1.90%)
Discrete Tax Adjustments	0.00%	0.00%
Other	0.00%	0.10%
Effective Income Tax Rate	22.60%	20.70%
Appalachian Power Co [Member]
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal Statutory Rate	21.00%	21.00%
State Income Tax, net of Federal Benefit	2.90%	3.20%
Tax Reform Excess ADIT Reversal	(5.80%)	(18.00%)
Production and Investment Tax Credits	0.00%	0.00%
Flow Through	1.70%	1.60%
AFUDC Equity	(0.70%)	(1.10%)
Parent Company Loss Benefit		(2.90%)
Discrete Tax Adjustments	(0.60%)	0.00%
Other	0.00%	0.10%
Effective Income Tax Rate	18.50%	3.90%
Indiana Michigan Power Co [Member]
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal Statutory Rate	21.00%	21.00%
State Income Tax, net of Federal Benefit	1.60%	1.30%
Tax Reform Excess ADIT Reversal	(17.30%)	(17.90%)
Production and Investment Tax Credits	(1.40%)	(1.70%)
Flow Through	(1.90%)	(1.00%)
AFUDC Equity	(0.60%)	(0.20%)
Parent Company Loss Benefit		(2.50%)
Discrete Tax Adjustments	0.00%	0.00%
Other	(0.20%)	0.00%
Effective Income Tax Rate	1.20%	(1.00%)
Ohio Power Co [Member]
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal Statutory Rate	21.00%	21.00%
State Income Tax, net of Federal Benefit	0.70%	0.70%
Tax Reform Excess ADIT Reversal	(7.80%)	(9.70%)
Production and Investment Tax Credits	0.00%	0.00%
Flow Through	0.90%	1.10%
AFUDC Equity	(0.60%)	(1.10%)
Parent Company Loss Benefit		0.00%
Discrete Tax Adjustments	0.00%	(4.00%)
Other	0.00%	0.20%
Effective Income Tax Rate	14.20%	8.20%
Public Service Co Of Oklahoma [Member]
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal Statutory Rate	21.00%	21.00%
State Income Tax, net of Federal Benefit	0.60%	4.70%
Tax Reform Excess ADIT Reversal	(15.30%)	(24.70%)
Production and Investment Tax Credits	(26.20%)	(8.20%)
Flow Through	0.60%	0.60%
AFUDC Equity	(0.70%)	(0.50%)
Parent Company Loss Benefit		0.00%
Discrete Tax Adjustments	0.00%	0.00%
Other	(0.80%)	(0.90%)
Effective Income Tax Rate	(20.80%)	(8.00%)
Southwestern Electric Power Co [Member]
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal Statutory Rate	21.00%	21.00%
State Income Tax, net of Federal Benefit	2.30%	(0.80%)
Tax Reform Excess ADIT Reversal	(4.90%)	(5.90%)
Production and Investment Tax Credits	(23.10%)	(5.10%)
Flow Through	(0.60%)	(0.70%)
AFUDC Equity	(0.50%)	(0.40%)
Parent Company Loss Benefit		0.00%
Discrete Tax Adjustments	0.00%	0.00%
Other	0.60%	0.10%
Effective Income Tax Rate	(5.20%)	8.20%