SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF PARENT COMPANY - AEPTCO PARENT - RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Long-term debt	$ 42,642,800	$ 40,143,200
Accrued interest	453,300	410,200
AEP TRANSMISSION COMPANY, LLC
Related Party Transaction [Line Items]
Long-term debt	5,768,100	5,414,400
Accrued interest	44,900	39,600
Affiliated Entity | AEP TRANSMISSION COMPANY, LLC
Related Party Transaction [Line Items]
Accounts receivable – affiliated companies	134,100	125,500
Parent Company
Related Party Transaction [Line Items]
Long-term debt	8,405,800	8,190,900
Interest income	107,900	181,000	$ 80,300
Parent Company | AEP TRANSMISSION COMPANY, LLC
Related Party Transaction [Line Items]
Accrued interest	45,000	39,600
Accounts receivable – affiliated companies	61,700	44,000
Interest income	241,100	218,000	177,800
Parent Company | Subsidiaries
Related Party Transaction [Line Items]
Interest expense	28,000	33,000	30,000
Parent Company | Subsidiaries | AEP TRANSMISSION COMPANY, LLC
Related Party Transaction [Line Items]
Long-term debt	5,800,000	5,400,000
Notes receivable – affiliated	8,600,000	5,400,000
Accrued interest	45,000	40,000
Accounts receivable – affiliated companies	62,000	44,000
Interest expense	238,000	215,000	177,000
Parent Company | Affiliated Entity
Related Party Transaction [Line Items]
Accounts receivable – affiliated companies	32,500	47,700
Parent Company | Long-Term Lending | Subsidiaries | AEP TRANSMISSION COMPANY, LLC
Related Party Transaction [Line Items]
Interest income	238,000	215,000	177,000
Parent Company | Short-Term Lending | Subsidiaries
Related Party Transaction [Line Items]
Interest income	84,000	164,000	71,000
Parent Company | Short-Term Lending | Affiliated Entity | AEP TRANSMISSION COMPANY, LLC
Related Party Transaction [Line Items]
Interest income	$ 3,000	$ 3,000	$ 915