FINANCING ACTIVITIES - Schedule of Maximum Minimum and Average Interest Rates for Funds Borrowed from and Loaned to AEP (Details) - Direct Borrowing - AEP TRANSMISSION COMPANY, LLC	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Short-Term Debt [Line Items]
Maximum Interest Rate for Funds Borrowed	4.10%	4.76%
Minimum Interest Rate For Funds Borrowed	3.83%	4.63%
Maximum Interest Rate for Funds Loaned	4.10%	4.76%
Minimum Interest Rate for Funds Loaned	3.83%	4.63%
Average Interest Rate for Funds Borrowed	3.91%	4.69%
Average Interest Rate for Funds Loaned	3.91%	4.68%