DERIVATIVES AND HEDGING - Schedule of Gain (Loss) Recognized on Risk Management Contracts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	$ 151.1	$ (322.8)	$ 693.7
Regulatory Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	73.0	(94.8)	52.6
Regulatory Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	270.7	169.7	299.7
Revenues | Vertically Integrated Utilities Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(23.7)	24.6	11.1
Revenues | Generation & Marketing
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(171.5)	(423.8)	313.8
Revenues | Electric Generation, Transmission and Distribution Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	3.0	2.5	5.0
Other Operation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(0.2)	(0.2)	4.8
Maintenance
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(0.2)	(0.8)	6.7
AEP Texas
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(0.2)	(0.6)	2.8
AEP Texas | Regulatory Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(0.1)	(0.2)	0.1
AEP Texas | Regulatory Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	(0.6)
AEP Texas | Revenues | Vertically Integrated Utilities Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
AEP Texas | Revenues | Generation & Marketing
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
AEP Texas | Revenues | Electric Generation, Transmission and Distribution Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
AEP Texas | Purchased Electricity, Fuel and Other Consumables Used for Electric Generation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
AEP Texas | Other Operation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	(0.1)	1.5
AEP Texas | Maintenance
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(0.1)	(0.3)	1.8
APCo
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	78.0	(18.6)	88.6
APCo | Regulatory Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	21.7	(21.9)	(0.1)
APCo | Regulatory Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	53.4	1.0	82.4
APCo | Revenues | Vertically Integrated Utilities Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
APCo | Revenues | Generation & Marketing
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
APCo | Revenues | Electric Generation, Transmission and Distribution Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.2	0.1	0.5
APCo | Purchased Electricity, Fuel and Other Consumables Used for Electric Generation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	2.7	2.3	4.5
APCo | Other Operation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.4
APCo | Maintenance
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	(0.1)	0.9
I&M
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(7.5)	29.2	19.6
I&M | Regulatory Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	2.8	(3.1)	(0.8)
I&M | Regulatory Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	13.4	7.8	8.6
I&M | Revenues | Vertically Integrated Utilities Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
I&M | Revenues | Generation & Marketing
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
I&M | Revenues | Electric Generation, Transmission and Distribution Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(23.9)	24.5	10.6
I&M | Purchased Electricity, Fuel and Other Consumables Used for Electric Generation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.2	0.1	0.1
I&M | Other Operation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.5
I&M | Maintenance
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	(0.1)	0.6
OPCo
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(1.8)	(14.1)	57.8
OPCo | Regulatory Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(1.8)	(14.0)	52.1
OPCo | Regulatory Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	3.7
OPCo | Revenues | Vertically Integrated Utilities Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
OPCo | Revenues | Generation & Marketing
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
OPCo | Revenues | Electric Generation, Transmission and Distribution Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
OPCo | Purchased Electricity, Fuel and Other Consumables Used for Electric Generation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
OPCo | Other Operation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.8
OPCo | Maintenance
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	(0.1)	1.2
PSO
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	119.6	58.8	103.7
PSO | Regulatory Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	26.0	(29.8)	3.6
PSO | Regulatory Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	93.6	88.7	98.5
PSO | Revenues | Vertically Integrated Utilities Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
PSO | Revenues | Generation & Marketing
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
PSO | Revenues | Electric Generation, Transmission and Distribution Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
PSO | Purchased Electricity, Fuel and Other Consumables Used for Electric Generation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.2
PSO | Other Operation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.6
PSO | Maintenance
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	(0.1)	0.8
SWEPCo
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	109.1	55.0	77.7
SWEPCo | Regulatory Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	14.2	(15.5)	(2.1)
SWEPCo | Regulatory Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	95.0	70.7	77.9
SWEPCo | Revenues | Vertically Integrated Utilities Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
SWEPCo | Revenues | Generation & Marketing
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
SWEPCo | Revenues | Electric Generation, Transmission and Distribution Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
SWEPCo | Purchased Electricity, Fuel and Other Consumables Used for Electric Generation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	0.0	0.0	0.0
SWEPCo | Other Operation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	(0.1)	0.0	0.8
SWEPCo | Maintenance
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total Gain (Loss) on Risk Management Contracts	$ 0.0	$ (0.2)	$ 1.1