v3.25.2
DERIVATIVES AND HEDGING - Schedule of the Notional Volume of Derivative Instruments (Details)
gal in Millions, MWh in Millions, MMBTU in Millions, $ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2025
USD ($)
MWh
MMBTU
gal
Dec. 31, 2024
USD ($)
MMBTU
MWh
gal
Power (MWhs)    
Derivative [Line Items]    
Notional amount, energy measure | MWh 373.7 282.4
Power (MWhs) | AEP Texas    
Derivative [Line Items]    
Notional amount, energy measure | MWh 0.0 0.0
Power (MWhs) | APCo    
Derivative [Line Items]    
Notional amount, energy measure | MWh 51.9 23.6
Power (MWhs) | I&M    
Derivative [Line Items]    
Notional amount, energy measure | MWh 16.0 7.7
Power (MWhs) | OPCo    
Derivative [Line Items]    
Notional amount, energy measure | MWh 1.9 2.0
Power (MWhs) | PSO    
Derivative [Line Items]    
Notional amount, energy measure | MWh 17.8 5.0
Power (MWhs) | SWEPCo    
Derivative [Line Items]    
Notional amount, energy measure | MWh 14.5 4.6
Natural Gas (MMBtus)    
Derivative [Line Items]    
Notional amount, energy measure | MMBTU 174.3 152.8
Natural Gas (MMBtus) | AEP Texas    
Derivative [Line Items]    
Notional amount, energy measure | MMBTU 0.0 0.0
Natural Gas (MMBtus) | APCo    
Derivative [Line Items]    
Notional amount, energy measure | MMBTU 45.3 42.2
Natural Gas (MMBtus) | I&M    
Derivative [Line Items]    
Notional amount, energy measure | MMBTU 0.0 0.0
Natural Gas (MMBtus) | OPCo    
Derivative [Line Items]    
Notional amount, energy measure | MMBTU 0.0 0.0
Natural Gas (MMBtus) | PSO    
Derivative [Line Items]    
Notional amount, energy measure | MMBTU 54.1 46.2
Natural Gas (MMBtus) | SWEPCo    
Derivative [Line Items]    
Notional amount, energy measure | MMBTU 22.3 15.4
Heating Oil and Gasoline (Gallons)    
Derivative [Line Items]    
Notional amount, volume | gal 6.6 7.9
Heating Oil and Gasoline (Gallons) | AEP Texas    
Derivative [Line Items]    
Notional amount, volume | gal 1.9 2.0
Heating Oil and Gasoline (Gallons) | APCo    
Derivative [Line Items]    
Notional amount, volume | gal 0.8 0.9
Heating Oil and Gasoline (Gallons) | I&M    
Derivative [Line Items]    
Notional amount, volume | gal 1.2 2.0
Heating Oil and Gasoline (Gallons) | OPCo    
Derivative [Line Items]    
Notional amount, volume | gal 1.0 1.1
Heating Oil and Gasoline (Gallons) | PSO    
Derivative [Line Items]    
Notional amount, volume | gal 0.6 0.7
Heating Oil and Gasoline (Gallons) | SWEPCo    
Derivative [Line Items]    
Notional amount, volume | gal 0.8 0.9
Interest Rate (USD)    
Derivative [Line Items]    
Derivative, notional amount $ 49.3 $ 59.3
Interest Rate (USD) | AEP Texas    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate (USD) | APCo    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate (USD) | I&M    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate (USD) | OPCo    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate (USD) | PSO    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate (USD) | SWEPCo    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate    
Derivative [Line Items]    
Derivative, notional amount 950.0 950.0
Interest Rate | AEP Texas    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate | APCo    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate | I&M    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate | OPCo    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate | PSO    
Derivative [Line Items]    
Derivative, notional amount 0.0 0.0
Interest Rate | SWEPCo    
Derivative [Line Items]    
Derivative, notional amount $ 0.0 $ 0.0