BENEFIT PLANS - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Life insurance administrative load	5.00%
Investment gains or losses period	5 years
Employer contribution cost	$ 379	$ 396	$ 329
Withdrawal liability	$ 12,000	$ 13,000
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	5.55%	5.05%
Minimum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.00%
Maximum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	11.50%
AEP TEXAS INC. | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	5.70%	5.20%
AEP TEXAS INC. | Minimum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.00%
AEP TEXAS INC. | Maximum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	11.50%
APPALACHIAN POWER COMPANY | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	5.55%	4.95%
APPALACHIAN POWER COMPANY | Minimum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.00%
APPALACHIAN POWER COMPANY | Maximum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	11.50%
PUBLIC SERVICE COMPANY OF OKLAHOMA | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	5.70%	5.20%
PUBLIC SERVICE COMPANY OF OKLAHOMA | Minimum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.00%
PUBLIC SERVICE COMPANY OF OKLAHOMA | Maximum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	11.50%
OHIO POWER COMPANY | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	6.00%	5.45%
OHIO POWER COMPANY | Minimum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.00%
OHIO POWER COMPANY | Maximum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	11.50%
INDIANA MICHIGAN POWER COMPANY | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	5.50%	5.05%
INDIANA MICHIGAN POWER COMPANY | Minimum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.00%
INDIANA MICHIGAN POWER COMPANY | Maximum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	11.50%
SOUTHWESTERN ELECTRIC POWER COMPANY | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	5.55%	5.00%
SOUTHWESTERN ELECTRIC POWER COMPANY | Minimum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.00%
SOUTHWESTERN ELECTRIC POWER COMPANY | Maximum | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	11.50%
Defined Contribution, Employer Matching Conditions One
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	100.00%
Employer matching contribution, percent of employees contribution	1.00%
Defined Contribution, Employer Matching Conditions One | AEP TEXAS INC.
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	100.00%
Employer matching contribution, percent of employees contribution	1.00%
Defined Contribution, Employer Matching Conditions One | APPALACHIAN POWER COMPANY
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	100.00%
Employer matching contribution, percent of employees contribution	1.00%
Defined Contribution, Employer Matching Conditions One | PUBLIC SERVICE COMPANY OF OKLAHOMA
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	100.00%
Employer matching contribution, percent of employees contribution	1.00%
Defined Contribution, Employer Matching Conditions One | OHIO POWER COMPANY
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	100.00%
Employer matching contribution, percent of employees contribution	1.00%
Defined Contribution, Employer Matching Conditions One | INDIANA MICHIGAN POWER COMPANY
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	100.00%
Employer matching contribution, percent of employees contribution	1.00%
Defined Contribution, Employer Matching Conditions One | SOUTHWESTERN ELECTRIC POWER COMPANY
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	100.00%
Employer matching contribution, percent of employees contribution	1.00%
Defined Contribution, Employer Matching Conditions Two
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	70.00%
Employer matching contribution, percent of employees contribution	5.00%
Defined Contribution, Employer Matching Conditions Two | AEP TEXAS INC.
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	70.00%
Employer matching contribution, percent of employees contribution	5.00%
Defined Contribution, Employer Matching Conditions Two | APPALACHIAN POWER COMPANY
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	70.00%
Employer matching contribution, percent of employees contribution	5.00%
Defined Contribution, Employer Matching Conditions Two | PUBLIC SERVICE COMPANY OF OKLAHOMA
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	70.00%
Employer matching contribution, percent of employees contribution	5.00%
Defined Contribution, Employer Matching Conditions Two | OHIO POWER COMPANY
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	70.00%
Employer matching contribution, percent of employees contribution	5.00%
Defined Contribution, Employer Matching Conditions Two | INDIANA MICHIGAN POWER COMPANY
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	70.00%
Employer matching contribution, percent of employees contribution	5.00%
Defined Contribution, Employer Matching Conditions Two | SOUTHWESTERN ELECTRIC POWER COMPANY
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	70.00%
Employer matching contribution, percent of employees contribution	5.00%