FINANCING ACTIVITIES - Schedule of Average Interest Rates for Funds Borrowed from and Loaned to Utility Money Pool (Details) - Utility	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
AEP TEXAS INC.
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	3.93%	4.69%
Average Interest Rate for Funds Loaned	4.06%	4.72%
AEP TRANSMISSION COMPANY, LLC
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	3.95%	4.68%
Average Interest Rate for Funds Loaned	4.01%	4.62%
APPALACHIAN POWER COMPANY
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.00%	4.69%
Average Interest Rate for Funds Loaned	4.01%	4.58%
INDIANA MICHIGAN POWER COMPANY
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	3.93%	4.69%
Average Interest Rate for Funds Loaned	3.93%	4.64%
OHIO POWER COMPANY
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.03%	4.65%
Average Interest Rate for Funds Loaned	3.80%	4.70%
PUBLIC SERVICE COMPANY OF OKLAHOMA
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.01%	4.67%
Average Interest Rate for Funds Loaned	0.00%	4.68%
SOUTHWESTERN ELECTRIC POWER COMPANY
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.06%	4.69%
Average Interest Rate for Funds Loaned	3.76%	4.65%