SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF PARENT COMPANY - AEPTCO PARENT - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
	Jun. 30, 2025	Jan. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Related Party Transaction [Line Items]
Proceeds from the Midwest Transmission Holdings Noncontrolling Interest Transaction, Net of Transaction Costs			$ 2,783	$ 0	$ 0
AEP TRANSMISSION COMPANY, LLC
Related Party Transaction [Line Items]
Proceeds from the Midwest Transmission Holdings Noncontrolling Interest Transaction, Net of Transaction Costs			$ 2,783	$ 0	$ 0
AEP TRANSMISSION COMPANY, LLC | Ohio Transmission And Indiana Michigan Transmission
Related Party Transaction [Line Items]
Ownership percentage selling		19.90%
Proceeds from noncontrolling interests, gross		$ 2,820
Proceeds from the Midwest Transmission Holdings Noncontrolling Interest Transaction, Net of Transaction Costs	$ 2,780