Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Income (Loss)	$ 2,488.1	$ 2,196.7	$ 1,919.8
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	250.5	6.9	(79.4)
Amortization of Pension and OPEB Deferred Costs, Net of Tax	(8.1)	(7.0)	(5.6)
Pension and OPEB Funded Status, Net of Tax	27.5	62.7	57.7
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	269.9	62.6	(27.3)
TOTAL COMPREHENSIVE INCOME (LOSS)	2,758.0	2,259.3	1,892.5
Total Comprehensive Income Attributable to Noncontrolling Interest	0.0	(3.4)	(1.3)
TOTAL COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO SHAREHOLDERS	2,758.0	2,262.7	1,893.8
Cash Flow Hedges, Tax	66.6	1.8	(21.1)
Amortization of Pension and OPEB Deferred Costs, Tax	(2.2)	(1.9)	(1.5)
Pension and OPEB Funded Status, Tax	7.3	16.7	15.3
AEP Texas Inc. [Member]
Net Income (Loss)	289.8	241.0	178.3
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	1.0	1.1	1.0
Amortization of Pension and OPEB Deferred Costs, Net of Tax	0.2	0.2	0.2
Pension and OPEB Funded Status, Net of Tax	1.2	2.6	1.1
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	2.4	3.9	2.3
TOTAL COMPREHENSIVE INCOME (LOSS)	292.2	244.9	180.6
Cash Flow Hedges, Tax	0.3	0.3	0.3
Amortization of Pension and OPEB Deferred Costs, Tax	0.0	0.0	0.0
Pension and OPEB Funded Status, Tax	0.3	0.7	0.3
AEP Transmission Co [Member]
Net Income (Loss)	591.7	423.4	439.7
Appalachian Power Co [Member]
Net Income (Loss)	348.9	369.7	306.3
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	8.3	(1.7)	(0.9)
Amortization of Pension and OPEB Deferred Costs, Net of Tax	(4.2)	(3.8)	(2.5)
Pension and OPEB Funded Status, Net of Tax	13.1	7.7	13.4
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	17.2	2.2	10.0
TOTAL COMPREHENSIVE INCOME (LOSS)	366.1	371.9	316.3
Cash Flow Hedges, Tax	2.2	(0.5)	(0.2)
Amortization of Pension and OPEB Deferred Costs, Tax	(1.1)	(1.0)	(0.7)
Pension and OPEB Funded Status, Tax	3.5	2.0	3.6
Indiana Michigan Power Co [Member]
Net Income (Loss)	279.8	284.8	269.4
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	1.6	1.6	1.6
Amortization of Pension and OPEB Deferred Costs, Net of Tax	(0.1)	(0.1)	(0.2)
Pension and OPEB Funded Status, Net of Tax	4.2	3.1	0.8
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	5.7	4.6	2.2
TOTAL COMPREHENSIVE INCOME (LOSS)	285.5	289.4	271.6
Cash Flow Hedges, Tax	0.4	0.4	0.4
Amortization of Pension and OPEB Deferred Costs, Tax	0.0	0.0	0.0
Pension and OPEB Funded Status, Tax	1.1	0.8	0.2
Ohio Power Co [Member]
Net Income (Loss)	253.6	271.4	297.1
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	0.0	0.0	(1.0)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)			(1.0)
TOTAL COMPREHENSIVE INCOME (LOSS)	253.6	271.4	296.1
Cash Flow Hedges, Tax	0.0	0.0	(0.3)
Public Service Co Of Oklahoma [Member]
Net Income (Loss)	141.1	123.0	137.6
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	(0.1)	(1.0)	(1.0)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	(0.1)	(1.0)	(1.0)
TOTAL COMPREHENSIVE INCOME (LOSS)	141.0	122.0	136.6
Cash Flow Hedges, Tax	0.0	(0.3)	(0.3)
Southwestern Electric Power Co [Member]
Net Income (Loss)	242.1	183.7	162.2
OTHER COMPREHENSIVE INCOME
Cash Flow Hedges, Net of Tax	1.5	1.5	1.5
Amortization of Pension and OPEB Deferred Costs, Net of Tax	(1.6)	(1.5)	(1.1)
Pension and OPEB Funded Status, Net of Tax	4.9	3.2	3.7
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	4.8	3.2	4.1
TOTAL COMPREHENSIVE INCOME (LOSS)	246.9	186.9	166.3
Total Comprehensive Income Attributable to Noncontrolling Interest	3.1	2.9	3.6
TOTAL COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO SHAREHOLDERS	243.8	184.0	162.7
Cash Flow Hedges, Tax	0.4	0.4	0.4
Amortization of Pension and OPEB Deferred Costs, Tax	(0.4)	(0.4)	(0.3)
Pension and OPEB Funded Status, Tax	$ 1.3	$ 0.9	$ 1.0