DERIVATIVES AND HEDGING - Schedule of Location and Fair Value of Derivative Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Derivative [Line Items]
Total Assets	$ 1,039.1	$ 1,167.4
Total Liabilities	780.4	1,083.4
Total MTM Derivative Contract Net Assets (Liabilities) Recognized	258.7	84.0
Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	479.1	611.8
Other Noncurrent Assets
Derivative [Line Items]
Total Assets	560.0	555.6
Other Current Liabilities
Derivative [Line Items]
Total Liabilities	351.7	646.7
Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	428.7	436.7
AEP Texas
Derivative [Line Items]
Total Assets	0.0	0.0
Total Liabilities	0.3	2.9
Total MTM Derivative Contract Net Assets (Liabilities) Recognized	(0.3)	(2.9)
AEP Texas | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
AEP Texas | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
AEP Texas | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.3	2.9
AEP Texas | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
APCo
Derivative [Line Items]
Total Assets	42.2	24.9
Total Liabilities	7.4	25.4
Total MTM Derivative Contract Net Assets (Liabilities) Recognized	34.8	(0.5)
APCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	40.2	24.6
APCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	2.0	0.3
APCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	6.6	18.5
APCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.8	6.9
I&M
Derivative [Line Items]
Total Assets	29.7	42.1
Total Liabilities	12.6	5.6
Total MTM Derivative Contract Net Assets (Liabilities) Recognized	17.1	36.5
I&M | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	28.5	30.1
I&M | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	1.2	12.0
I&M | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	10.5	5.4
I&M | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	2.1	0.2
OPCo
Derivative [Line Items]
Total Assets	0.0	0.0
Total Liabilities	47.7	50.8
Total MTM Derivative Contract Net Assets (Liabilities) Recognized	(47.7)	(50.8)
OPCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
OPCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
OPCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	7.5	6.9
OPCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	40.2	43.9
PSO
Derivative [Line Items]
Total Assets	23.9	19.7
Total Liabilities	7.8	30.7
Total MTM Derivative Contract Net Assets (Liabilities) Recognized	16.1	(11.0)
PSO | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	22.3	19.7
PSO | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	1.6	0.0
PSO | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	7.6	29.7
PSO | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.2	1.0
SWEPCo
Derivative [Line Items]
Total Assets	19.1	12.5
Total Liabilities	3.4	16.6
Total MTM Derivative Contract Net Assets (Liabilities) Recognized	15.7	(4.1)
SWEPCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	19.1	12.0
SWEPCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.5
SWEPCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	3.4	14.9
SWEPCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	1.7
Commodity | Not Designated as Hedging Instrument | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	425.0	555.1
Commodity | Not Designated as Hedging Instrument | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	475.4	468.8
Commodity | Not Designated as Hedging Instrument | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	304.1	588.0
Commodity | Not Designated as Hedging Instrument | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	390.7	377.6
Commodity | Not Designated as Hedging Instrument | AEP Texas | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Not Designated as Hedging Instrument | AEP Texas | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Not Designated as Hedging Instrument | AEP Texas | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.3	0.2
Commodity | Not Designated as Hedging Instrument | AEP Texas | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Not Designated as Hedging Instrument | APCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	40.2	24.6
Commodity | Not Designated as Hedging Instrument | APCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	2.0	0.3
Commodity | Not Designated as Hedging Instrument | APCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	6.6	18.5
Commodity | Not Designated as Hedging Instrument | APCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.8	6.9
Commodity | Not Designated as Hedging Instrument | I&M | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	28.5	30.1
Commodity | Not Designated as Hedging Instrument | I&M | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	1.2	12.0
Commodity | Not Designated as Hedging Instrument | I&M | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	10.5	5.4
Commodity | Not Designated as Hedging Instrument | I&M | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	2.1	0.2
Commodity | Not Designated as Hedging Instrument | OPCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Not Designated as Hedging Instrument | OPCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Not Designated as Hedging Instrument | OPCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	7.5	6.9
Commodity | Not Designated as Hedging Instrument | OPCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	40.2	43.9
Commodity | Not Designated as Hedging Instrument | PSO | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	22.3	19.7
Commodity | Not Designated as Hedging Instrument | PSO | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	1.6	0.0
Commodity | Not Designated as Hedging Instrument | PSO | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	7.6	29.7
Commodity | Not Designated as Hedging Instrument | PSO | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.2	1.0
Commodity | Not Designated as Hedging Instrument | SWEPCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	19.1	12.0
Commodity | Not Designated as Hedging Instrument | SWEPCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.5
Commodity | Not Designated as Hedging Instrument | SWEPCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	3.4	14.9
Commodity | Not Designated as Hedging Instrument | SWEPCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	1.7
Commodity | Designated as Hedging Instrument | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	54.1	56.7
Commodity | Designated as Hedging Instrument | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	84.6	86.8
Commodity | Designated as Hedging Instrument | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	11.3	8.2
Commodity | Designated as Hedging Instrument | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	2.7	2.2
Commodity | Designated as Hedging Instrument | AEP Texas | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | AEP Texas | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | AEP Texas | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | AEP Texas | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | APCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | APCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | APCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | APCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | I&M | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | I&M | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | I&M | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | I&M | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | OPCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | OPCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | OPCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | OPCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | PSO | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | PSO | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | PSO | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | PSO | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | SWEPCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | SWEPCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Commodity | Designated as Hedging Instrument | SWEPCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Commodity | Designated as Hedging Instrument | SWEPCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	36.3	50.5
Interest Rate (USD) | Designated as Hedging Instrument | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	35.3	56.9
Interest Rate (USD) | Designated as Hedging Instrument | AEP Texas | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | AEP Texas | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | AEP Texas | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	2.7
Interest Rate (USD) | Designated as Hedging Instrument | AEP Texas | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | APCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | APCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | APCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | APCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | I&M | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | I&M | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | I&M | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | I&M | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | OPCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | OPCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | OPCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | OPCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | PSO | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | PSO | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | PSO | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | PSO | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | SWEPCo | Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | SWEPCo | Other Noncurrent Assets
Derivative [Line Items]
Total Assets	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | SWEPCo | Other Current Liabilities
Derivative [Line Items]
Total Liabilities	0.0	0.0
Interest Rate (USD) | Designated as Hedging Instrument | SWEPCo | Other Noncurrent Liabilities
Derivative [Line Items]
Total Liabilities	$ 0.0	$ 0.0