VOLUNTARY SEVERANCE PROGRAM - Summary From Program (Details) $ in Millions	3 Months Ended
	Jun. 30, 2024 USD ($)
Restructuring Cost and Reserve [Line Items]
Severance Expense Incurred	$ 122
AEP TEXAS INC.
Restructuring Cost and Reserve [Line Items]
Severance Expense Incurred	20
AEP TRANSMISSION COMPANY, LLC
Restructuring Cost and Reserve [Line Items]
Severance Expense Incurred	11
APPALACHIAN POWER COMPANY
Restructuring Cost and Reserve [Line Items]
Severance Expense Incurred	26
INDIANA MICHIGAN POWER COMPANY
Restructuring Cost and Reserve [Line Items]
Severance Expense Incurred	15
OHIO POWER COMPANY
Restructuring Cost and Reserve [Line Items]
Severance Expense Incurred	15
PUBLIC SERVICE COMPANY OF OKLAHOMA
Restructuring Cost and Reserve [Line Items]
Severance Expense Incurred	10
SOUTHWESTERN ELECTRIC POWER COMPANY
Restructuring Cost and Reserve [Line Items]
Severance Expense Incurred	$ 17