FINANCING ACTIVITIES - Schedule of Average Interest Rates for Funds Borrowed from and Loaned to Utility Money Pool (Details) - Utility	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
AEP Texas
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.60%	5.48%	5.46%
Average Interest Rate for Funds Loaned	4.19%	5.45%	5.71%
AEPTCo
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.48%	5.51%	5.41%
Average Interest Rate for Funds Loaned	4.44%	5.50%	5.56%
APCo
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.50%	5.51%	5.54%
Average Interest Rate for Funds Loaned	4.46%	5.41%	5.54%
I&M
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.69%	5.40%	5.14%
Average Interest Rate for Funds Loaned	4.12%	5.44%	5.57%
OPCo
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.43%	5.70%	5.43%
Average Interest Rate for Funds Loaned	4.70%	5.20%	5.60%
PSO
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.51%	5.50%	5.51%
Average Interest Rate for Funds Loaned	4.68%	4.79%	5.35%
SWEPCo
Short-Term Debt [Line Items]
Average Interest Rate for Funds Borrowed	4.67%	5.41%	5.34%
Average Interest Rate for Funds Loaned	4.29%	4.78%	5.72%