FINANCING ACTIVITIES - Schedule of Utility Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits (Details) - Utility - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
AEP TEXAS INC.
Short-Term Debt [Line Items]
Maximum Borrowings	$ 374.6	$ 477.5
Maximum Loans	274.3	42.0
Average Borrowings	233.8	216.8
Average Loans	165.1	12.9
Authorized Short-term Borrowing Limit	600.0	600.0
AEP TEXAS INC. | Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	(284.9)	(103.7)
AEP TRANSMISSION COMPANY, LLC
Short-Term Debt [Line Items]
Maximum Borrowings	313.3	471.3
Maximum Loans	332.0	309.4
Average Borrowings	71.8	135.6
Average Loans	138.4	70.5
Authorized Short-term Borrowing Limit	820.0	820.0
AEP TRANSMISSION COMPANY, LLC | Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	(72.9)	(62.8)
APPALACHIAN POWER COMPANY
Short-Term Debt [Line Items]
Maximum Borrowings	399.5	388.6
Maximum Loans	132.3	19.8
Average Borrowings	102.6	283.5
Average Loans	29.7	19.0
Authorized Short-term Borrowing Limit	750.0	750.0
APPALACHIAN POWER COMPANY | Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	(77.3)	(320.7)
INDIANA MICHIGAN POWER COMPANY
Short-Term Debt [Line Items]
Maximum Borrowings	135.8	475.3
Maximum Loans	8.4	112.2
Average Borrowings	58.8	84.0
Average Loans	3.9	44.2
Authorized Short-term Borrowing Limit	500.0	500.0
INDIANA MICHIGAN POWER COMPANY | Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	(126.8)	(63.3)
OHIO POWER COMPANY
Short-Term Debt [Line Items]
Maximum Borrowings	310.0	485.7
Maximum Loans	183.4	64.7
Average Borrowings	180.5	183.0
Average Loans	94.2	40.2
Authorized Short-term Borrowing Limit	600.0	500.0
OHIO POWER COMPANY | Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	114.9	(110.5)
PUBLIC SERVICE COMPANY OF OKLAHOMA
Short-Term Debt [Line Items]
Maximum Borrowings	308.9	375.0
Maximum Loans	314.5	121.5
Average Borrowings	171.4	92.5
Average Loans	287.7	49.6
Authorized Short-term Borrowing Limit	750.0	750.0
PUBLIC SERVICE COMPANY OF OKLAHOMA | Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	232.0	(54.4)
SOUTHWESTERN ELECTRIC POWER COMPANY
Short-Term Debt [Line Items]
Maximum Borrowings	362.2	401.6
Maximum Loans	59.3	25.8
Average Borrowings	249.5	150.7
Average Loans	57.3	16.5
Authorized Short-term Borrowing Limit	750.0	750.0
SOUTHWESTERN ELECTRIC POWER COMPANY | Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	$ (275.0)	$ (88.7)