v3.26.1
FINANCING ACTIVITIES - Schedule of Maximum, Minimum and Average Interest Rates for Funds Borrowed from and Loaned to the Nonutility Money Pool (Details) - Nonutility
6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
AEP TEXAS INC.    
Short-Term Debt [Line Items]    
Maximum Interest Rate for Funds Loaned 4.13% 4.76%
Minimum Interest Rate for Funds Loaned 3.83% 4.64%
Average Interest Rate for Funds Loaned 3.99% 4.70%
SOUTHWESTERN ELECTRIC POWER COMPANY    
Short-Term Debt [Line Items]    
Maximum Interest Rate for Funds Loaned 0.00% 4.76%
Minimum Interest Rate for Funds Loaned 0.00% 4.64%
Average Interest Rate for Funds Loaned 0.00% 4.70%