FINANCING ACTIVITIES - Schedule of Fees Paid to AEP Credit for Customer Accounts Receivable Sold (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	$ 19,969.7	$ 19,454.8	$ 19,391.7
APPALACHIAN POWER COMPANY
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	4,038.8	3,740.6	3,520.7
INDIANA MICHIGAN POWER COMPANY
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	2,603.5	2,522.3	2,659.7
OHIO POWER COMPANY
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	3,780.9	3,802.8	3,672.1
PUBLIC SERVICE COMPANY OF OKLAHOMA
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	1,849.5	1,976.6	1,875.7
SOUTHWESTERN ELECTRIC POWER COMPANY
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	2,043.3	2,192.1	2,283.2
Servicing Contracts | APPALACHIAN POWER COMPANY
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	15.5	16.9	9.4
Servicing Contracts | INDIANA MICHIGAN POWER COMPANY
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	15.4	16.3	9.7
Servicing Contracts | OHIO POWER COMPANY
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	29.7	29.5	29.8
Servicing Contracts | PUBLIC SERVICE COMPANY OF OKLAHOMA
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	14.2	15.3	7.4
Servicing Contracts | SOUTHWESTERN ELECTRIC POWER COMPANY
Disaggregation of Revenue [Line Items]
Total Revenues from Contracts with Customers	$ 17.6	$ 18.5	$ 9.4