PROPERTY, PLANT, AND EQUIPMENT - Total Plant Balances (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Generation	$ 24,694.5	$ 23,862.7
Transmission	38,871.9	35,903.6
Distribution	31,061.9	28,989.9
Other	6,544.9	5,986.1
CWIP	6,321.5	5,480.6
Less: Accumulated Depreciation	25,794.0	24,093.8
Total Regulated Property, Plant and Equipment - Net	81,700.7	76,129.1
Nonregulated Property, Plant and Equipment - Net	714.9	564.3
TOTAL PROPERTY, PLANT AND EQUIPMENT – NET	82,415.6	76,693.4
AEP TEXAS INC.
Property, Plant and Equipment [Line Items]
Generation	0.0	0.0
Transmission	7,546.2	6,812.6
Distribution	6,250.5	5,798.8
Other	1,172.9	1,142.9
CWIP	1,118.0	904.6
Less: Accumulated Depreciation	2,045.7	1,886.7
Total Regulated Property, Plant and Equipment - Net	14,041.9	12,772.2
Nonregulated Property, Plant and Equipment - Net	1.6	1.8
TOTAL PROPERTY, PLANT AND EQUIPMENT – NET	14,043.5	12,774.0
AEP TRANSMISSION COMPANY, LLC
Property, Plant and Equipment [Line Items]
Generation	0.0	0.0
Transmission	14,913.4	13,723.9
Distribution	0.0	0.0
Other	515.9	501.2
CWIP	1,965.4	1,563.7
Less: Accumulated Depreciation	1,578.5	1,291.4
Total Regulated Property, Plant and Equipment - Net	15,816.2	14,497.4
Nonregulated Property, Plant and Equipment - Net	0.3	0.3
TOTAL PROPERTY, PLANT AND EQUIPMENT – NET	15,816.5	14,497.7
APPALACHIAN POWER COMPANY
Property, Plant and Equipment [Line Items]
Generation	7,272.6	7,041.3
Transmission	5,001.5	4,711.8
Distribution	5,568.5	5,176.6
Other	1,023.9	943.7
CWIP	742.6	709.2
Less: Accumulated Depreciation	6,030.9	5,684.0
Total Regulated Property, Plant and Equipment - Net	13,578.2	12,898.6
Nonregulated Property, Plant and Equipment - Net	34.3	32.9
TOTAL PROPERTY, PLANT AND EQUIPMENT – NET	13,612.5	12,931.5
INDIANA MICHIGAN POWER COMPANY
Property, Plant and Equipment [Line Items]
Generation	5,438.5	5,588.7
Transmission	1,957.8	1,906.4
Distribution	3,535.0	3,254.0
Other	948.3	856.8
CWIP	330.1	294.1
Less: Accumulated Depreciation	4,607.0	4,353.7
Total Regulated Property, Plant and Equipment - Net	7,602.7	7,546.3
Nonregulated Property, Plant and Equipment - Net	76.6	82.7
TOTAL PROPERTY, PLANT AND EQUIPMENT – NET	7,679.3	7,629.0
OHIO POWER COMPANY
Property, Plant and Equipment [Line Items]
Generation	0.0	0.0
Transmission	3,663.9	3,395.1
Distribution	7,244.0	6,839.4
Other	1,245.3	1,114.4
CWIP	691.1	654.0
Less: Accumulated Depreciation	2,883.0	2,712.7
Total Regulated Property, Plant and Equipment - Net	9,961.3	9,290.2
Nonregulated Property, Plant and Equipment - Net	9.8	9.7
TOTAL PROPERTY, PLANT AND EQUIPMENT – NET	9,971.1	9,299.9
PUBLIC SERVICE COMPANY OF OKLAHOMA
Property, Plant and Equipment [Line Items]
Generation	2,772.4	2,695.5
Transmission	1,345.3	1,228.3
Distribution	3,698.8	3,450.8
Other	546.8	502.7
CWIP	378.8	313.7
Less: Accumulated Depreciation	2,214.7	2,083.6
Total Regulated Property, Plant and Equipment - Net	6,527.4	6,107.4
Nonregulated Property, Plant and Equipment - Net	4.9	4.9
TOTAL PROPERTY, PLANT AND EQUIPMENT – NET	6,532.3	6,112.3
SOUTHWESTERN ELECTRIC POWER COMPANY
Property, Plant and Equipment [Line Items]
Generation	5,287.5	4,790.7
Transmission	2,863.8	2,660.6
Distribution	3,007.1	2,824.1
Other	682.7	544.1
CWIP	627.3	555.8
Less: Accumulated Depreciation	3,048.5	2,840.8
Total Regulated Property, Plant and Equipment - Net	9,419.9	8,534.5
Nonregulated Property, Plant and Equipment - Net	26.2	23.9
TOTAL PROPERTY, PLANT AND EQUIPMENT – NET	$ 9,446.1	$ 8,558.4