Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Operating Activities
Net Income (Loss)	$ 1,238.9	$ 1,152.6
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	1,595.0	1,403.6
Deferred Income Taxes	21.4	86.7
Loss on the Expected Sale of the Kentucky Operations	68.8	0.0
Allowance for Equity Funds Used During Construction	(59.6)	(66.9)
Mark-to-Market of Risk Management Contracts	431.4	26.1
Property Taxes	191.6	167.3
Deferred Fuel Over/Under-Recovery, Net	(599.5)	(1,218.2)
Gain (Loss) on Disposition of Assets	(116.3)	0.0
Change in Other Noncurrent Assets	(49.3)	(184.7)
Change in Other Noncurrent Liabilities	144.5	163.5
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(445.8)	(215.5)
Fuel, Materials and Supplies	(110.5)	132.3
Accounts Payable	484.8	97.5
Accrued Taxes, Net	(218.2)	(237.4)
Other Current Assets	69.9	10.4
Other Current Liabilities	158.1	(273.4)
Net Cash Flows from (Used for) Operating Activities	2,990.7	1,043.9
Investing Activities
Construction Expenditures	(3,138.1)	(2,784.8)
Purchases of Investment Securities	(1,254.8)	(1,162.8)
Sales of Investment Securities	1,244.9	1,131.8
Acquisitions of Nuclear Fuel	(67.7)	(63.0)
Proceeds from Sale of Property, Plant, and Equipment	208.5	13.2
Other Investing Activities	15.5	20.1
Net Cash Flows from (Used for) Investing Activities	(4,199.0)	(3,229.8)
Financing Activities
Issuance of Common Stock	812.7	256.9
Issuance of Long-term Debt	2,639.1	3,055.1
Issuance of Short-term Debt with Original Maturities greater than 90 Days	271.0	1,178.5
Change in Short-term Debt with Original Maturities less than 90 Days, Net	(268.9)	(437.8)
Retirement of Long-term Debt	(582.4)	(998.1)
Redemption of Short-term Debt with Original Maturities Greater than 90 Days	(486.1)	(92.0)
Principal Payments for Finance Leases Obligations	(106.2)	(30.3)
Dividends Paid on Common Stock	(803.5)	(746.5)
Other Financing Activities	(97.6)	(78.5)
Net Cash Flows from (Used for) Financing Activities	1,378.1	2,107.3
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	169.8	(78.6)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	451.4	438.3
Cash and Cash Equivalents at Beginning of Period	403.4
Cash, Cash Equivalents and Restricted Cash at End of Period	621.2	359.7
Cash and Cash Equivalents at End of Period	575.3
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	591.2	559.9
Net Cash Paid (Received) for Income Taxes	95.5	8.6
Noncash Acquisitions Under Finance Leases	13.7	16.3
Construction Expenditures Included in Current Liabilities as of March 31,	849.1	789.3
Dry Lake Solar Project
Investing Activities
Acquisitions of Assets	0.0	(114.3)
North Central Wind Energy Facilities
Investing Activities
Acquisitions of Assets	(1,207.3)	(270.0)
Mineral Rights
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Gain (Loss) on Disposition of Assets	(116.3)	0.0
Kentucky Power Co [Member]
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Loss on the Expected Sale of the Kentucky Operations	68.8	0.0
Flat Ridge II
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Impairment of Equity Method Investment	185.5	0.0
AEP Texas Inc. [Member]
Operating Activities
Net Income (Loss)	159.6	125.9
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	225.0	199.5
Deferred Income Taxes	24.6	14.0
Allowance for Equity Funds Used During Construction	(8.0)	(7.5)
Mark-to-Market of Risk Management Contracts	(0.2)	0.0
Property Taxes	(54.8)	(49.7)
Change in Other Noncurrent Assets	(25.9)	(42.0)
Change in Other Noncurrent Liabilities	32.1	17.2
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(70.3)	(43.8)
Fuel, Materials and Supplies	(24.1)	0.5
Accounts Payable	17.9	(10.3)
Accrued Taxes, Net	34.0	47.4
Other Current Assets	(0.8)	0.7
Other Current Liabilities	31.9	(29.3)
Net Cash Flows from (Used for) Operating Activities	341.0	222.6
Investing Activities
Construction Expenditures	(647.6)	(531.2)
Change in Advances to Affiliates, Net	(634.0)	(47.2)
Other Investing Activities	22.3	21.3
Net Cash Flows from (Used for) Investing Activities	(1,259.3)	(557.1)
Financing Activities
Capital Contributions from Parent	1.3	0.0
Issuance of Long-term Debt	1,188.6	444.3
Change in Advances from Affiliates, Net	(26.9)	(67.1)
Retirement of Long-term Debt	(242.0)	(40.9)
Principal Payments for Finance Leases Obligations	(3.4)	(3.3)
Other Financing Activities	0.0	0.7
Net Cash Flows from (Used for) Financing Activities	917.6	333.7
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(0.7)	(0.8)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	30.5	28.8
Cash and Cash Equivalents at Beginning of Period	0.1
Cash, Cash Equivalents and Restricted Cash at End of Period	29.8	28.0
Cash and Cash Equivalents at End of Period	0.1
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	88.8	82.0
Net Cash Paid (Received) for Income Taxes	5.9	(9.2)
Noncash Acquisitions Under Finance Leases	3.0	2.4
Construction Expenditures Included in Current Liabilities as of March 31,	135.9	125.5
AEP Transmission Co [Member]
Operating Activities
Net Income (Loss)	273.9	300.3
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	168.8	143.0
Deferred Income Taxes	37.3	55.5
Allowance for Equity Funds Used During Construction	(30.9)	(33.3)
Property Taxes	101.4	93.3
Provision for Refund Affiliated	56.4	17.6
Change in Other Noncurrent Assets	1.8	(4.5)
Change in Other Noncurrent Liabilities	44.3	10.5
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(36.7)	(22.2)
Fuel, Materials and Supplies	(2.2)	(0.5)
Accounts Payable	13.1	0.1
Accrued Taxes, Net	(107.6)	(106.2)
Other Current Assets	0.9	0.7
Other Current Liabilities	(0.9)	(1.5)
Net Cash Flows from (Used for) Operating Activities	463.2	435.2
Investing Activities
Construction Expenditures	(730.9)	(719.7)
Change in Advances to Affiliates, Net	(109.8)	(4.5)
Other Investing Activities	(8.0)	(3.4)
Net Cash Flows from (Used for) Investing Activities	(848.7)	(727.6)
Financing Activities
Capital Contributions from Parent	2.8	184.0
Issuance of Long-term Debt	540.9	0.0
Change in Advances from Affiliates, Net	(68.2)	108.6
Dividends Paid on Common Stock	(90.0)	0.0
Other Financing Activities	0.0	(0.2)
Net Cash Flows from (Used for) Financing Activities	385.5	292.4
Net Increase (Decrease) in Cash and Cash Equivalents	0.0	0.0
Cash and Cash Equivalents at Beginning of Period	0.0	0.0
Cash and Cash Equivalents at End of Period	0.0	0.0
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	74.0	66.6
Net Cash Paid (Received) for Income Taxes	39.7	21.6
Construction Expenditures Included in Current Liabilities as of March 31,	228.7	267.9
Appalachian Power Co [Member]
Operating Activities
Net Income (Loss)	210.4	188.8
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	288.1	271.2
Deferred Income Taxes	17.1	4.0
Allowance for Equity Funds Used During Construction	(4.6)	(7.8)
Mark-to-Market of Risk Management Contracts	(38.5)	(16.8)
Deferred Fuel Over/Under-Recovery, Net	(312.1)	(21.1)
Change in Other Noncurrent Assets	(42.3)	(70.2)
Change in Other Noncurrent Liabilities	(0.2)	12.5
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	65.4	23.7
Fuel, Materials and Supplies	(75.4)	45.4
Increase (Decrease) in Margin Deposits Outstanding	64.5	(12.5)
Accounts Payable	162.8	(3.9)
Accrued Taxes, Net	(5.7)	(26.6)
Other Current Assets	0.7	3.7
Other Current Liabilities	(0.7)	(23.0)
Net Cash Flows from (Used for) Operating Activities	329.5	367.4
Investing Activities
Construction Expenditures	(450.8)	(374.8)
Change in Advances to Affiliates, Net	1.4	(70.3)
Other Investing Activities	23.3	11.1
Net Cash Flows from (Used for) Investing Activities	(426.1)	(434.0)
Financing Activities
Capital Contributions from Parent	2.8	0.0
Issuance of Long-term Debt	103.3	494.0
Change in Advances from Affiliates, Net	149.9	(18.6)
Retirement of Long-term Debt	(117.1)	(380.0)
Principal Payments for Finance Leases Obligations	(4.0)	(3.9)
Dividends Paid on Common Stock	(37.5)	(25.0)
Other Financing Activities	0.2	0.4
Net Cash Flows from (Used for) Financing Activities	97.6	66.9
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	1.0	0.3
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	20.1	22.7
Cash and Cash Equivalents at Beginning of Period	2.5
Cash, Cash Equivalents and Restricted Cash at End of Period	21.1	23.0
Cash and Cash Equivalents at End of Period	4.9
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	104.9	104.7
Net Cash Paid (Received) for Income Taxes	1.0	35.8
Noncash Acquisitions Under Finance Leases	0.5	0.9
Construction Expenditures Included in Current Liabilities as of March 31,	121.2	98.0
Indiana Michigan Power Co [Member]
Operating Activities
Net Income (Loss)	156.7	128.0
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	268.6	218.1
Rockport Plant, Unit 2 Operating Lease Amortization	0.0	33.9
Deferred Income Taxes	0.3	(8.2)
Amortization (Deferral) of Incremental Nuclear Refueling Outage Expenses, Net	(38.3)	(14.3)
Allowance for Equity Funds Used During Construction	(5.4)	(7.0)
Mark-to-Market of Risk Management Contracts	(11.6)	(3.1)
Amortization of Nuclear Fuel	39.0	40.4
Deferred Fuel Over/Under-Recovery, Net	(17.5)	(5.7)
Change in Other Noncurrent Assets	3.3	11.7
Change in Other Noncurrent Liabilities	22.2	26.2
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	24.0	(0.4)
Fuel, Materials and Supplies	4.5	27.1
Accounts Payable	13.6	16.4
Accrued Taxes, Net	(2.4)	(5.3)
Operating Lease, Payments	0.0	(36.9)
Other Current Assets	15.2	2.0
Other Current Liabilities	(20.1)	(29.1)
Net Cash Flows from (Used for) Operating Activities	452.1	393.8
Investing Activities
Construction Expenditures	(262.5)	(241.0)
Change in Advances to Affiliates, Net	(1.0)	(86.6)
Purchases of Investment Securities	(1,253.2)	(1,149.7)
Sales of Investment Securities	1,229.9	1,122.7
Acquisitions of Nuclear Fuel	(67.7)	(63.0)
Other Investing Activities	3.0	4.5
Net Cash Flows from (Used for) Investing Activities	(351.5)	(413.1)
Financing Activities
Capital Contributions from Parent	1.3	0.0
Issuance of Long-term Debt	72.8	507.0
Change in Advances from Affiliates, Net	(42.8)	(103.0)
Retirement of Long-term Debt	(40.7)	(282.7)
Principal Payments for Finance Leases Obligations	(40.1)	(3.3)
Dividends Paid on Common Stock	(50.0)	(100.0)
Other Financing Activities	0.4	0.5
Net Cash Flows from (Used for) Financing Activities	(99.1)	18.5
Net Increase (Decrease) in Cash and Cash Equivalents	1.5	(0.8)
Cash and Cash Equivalents at Beginning of Period	1.3	3.3
Cash and Cash Equivalents at End of Period	2.8	2.5
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	59.2	52.2
Net Cash Paid (Received) for Income Taxes	(4.9)	4.1
Noncash Acquisitions Under Finance Leases	0.4	2.8
Construction Expenditures Included in Current Liabilities as of March 31,	68.2	59.9
Ohio Power Co [Member]
Operating Activities
Net Income (Loss)	158.0	142.2
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	146.2	151.7
Deferred Income Taxes	13.8	21.5
Carrying Costs Income	(0.2)	(1.0)
Allowance for Equity Funds Used During Construction	(6.4)	(5.6)
Mark-to-Market of Risk Management Contracts	(44.3)	(4.8)
Property Taxes	178.6	154.2
Change in Other Noncurrent Assets	(53.1)	(45.8)
Change in Other Noncurrent Liabilities	44.3	7.2
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(35.8)	(47.9)
Fuel, Materials and Supplies	(10.1)	(3.0)
Accounts Payable	78.2	(13.6)
Increase (Decrease) in Contract with Customer, Liability	142.5	21.7
Accrued Taxes, Net	(246.8)	(222.8)
Other Current Assets	12.2	0.8
Other Current Liabilities	35.6	(7.8)
Net Cash Flows from (Used for) Operating Activities	412.9	148.0
Investing Activities
Construction Expenditures	(376.4)	(353.3)
Change in Advances to Affiliates, Net	(14.0)	0.0
Other Investing Activities	12.6	6.6
Net Cash Flows from (Used for) Investing Activities	(377.8)	(346.7)
Financing Activities
Capital Contributions from Parent	0.7	0.0
Issuance of Long-term Debt	0.0	445.8
Change in Advances from Affiliates, Net	0.0	(202.9)
Retirement of Long-term Debt	(0.1)	(0.1)
Principal Payments for Finance Leases Obligations	(2.4)	(2.4)
Dividends Paid on Common Stock	(30.0)	(43.8)
Other Financing Activities	0.6	0.5
Net Cash Flows from (Used for) Financing Activities	(31.2)	197.1
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	3.9	(1.6)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	3.0	7.4
Cash and Cash Equivalents at Beginning of Period	3.0
Cash, Cash Equivalents and Restricted Cash at End of Period	6.9	5.8
Cash and Cash Equivalents at End of Period	6.9
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	56.8	58.4
Net Cash Paid (Received) for Income Taxes	21.4	1.3
Noncash Acquisitions Under Finance Leases	1.2	0.9
Construction Expenditures Included in Current Liabilities as of March 31,	92.9	70.9
Public Service Co Of Oklahoma [Member]
Operating Activities
Net Income (Loss)	48.8	43.4
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	113.2	100.1
Deferred Income Taxes	(20.4)	25.7
Allowance for Equity Funds Used During Construction	(1.3)	(1.0)
Mark-to-Market of Risk Management Contracts	(56.2)	(12.7)
Property Taxes	(24.4)	(21.8)
Deferred Fuel Over/Under-Recovery, Net	(124.2)	(724.1)
Change in Other Noncurrent Assets	(7.4)	(16.6)
Change in Other Noncurrent Liabilities	10.4	0.4
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(30.6)	(22.1)
Fuel, Materials and Supplies	(10.8)	8.5
Accounts Payable	123.7	11.7
Accrued Taxes, Net	23.9	59.2
Other Current Assets	(16.8)	(4.4)
Other Current Liabilities	9.9	(22.0)
Net Cash Flows from (Used for) Operating Activities	37.8	(575.7)
Investing Activities
Construction Expenditures	(200.2)	(145.9)
Acquisitions of Assets	549.3	122.8
Other Investing Activities	2.3	1.3
Net Cash Flows from (Used for) Investing Activities	(747.2)	(267.4)
Financing Activities
Capital Contributions from Parent	2.2	625.0
Issuance of Long-term Debt	500.0	500.0
Change in Advances from Affiliates, Net	211.1	(20.3)
Retirement of Long-term Debt	(0.3)	(250.3)
Principal Payments for Finance Leases Obligations	(1.6)	(1.7)
Dividends Paid on Common Stock	0.0	(10.0)
Other Financing Activities	0.3	0.4
Net Cash Flows from (Used for) Financing Activities	711.7	843.1
Net Increase (Decrease) in Cash and Cash Equivalents	2.3	0.0
Cash and Cash Equivalents at Beginning of Period	1.3	2.6
Cash and Cash Equivalents at End of Period	3.6	2.6
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	38.1	32.2
Net Cash Paid (Received) for Income Taxes	12.2	(65.0)
Noncash Acquisitions Under Finance Leases	1.1	2.3
Construction Expenditures Included in Current Liabilities as of March 31,	41.6	27.9
Southwestern Electric Power Co [Member]
Operating Activities
Net Income (Loss)	123.9	100.8
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	156.0	142.6
Deferred Income Taxes	(1.4)	8.1
Allowance for Equity Funds Used During Construction	(2.4)	(4.0)
Mark-to-Market of Risk Management Contracts	(36.6)	(13.1)
Property Taxes	(44.0)	(41.7)
Deferred Fuel Over/Under-Recovery, Net	(53.6)	(470.6)
Change in Regulatory Assets	0.3	(50.6)
Change in Other Noncurrent Assets	45.1	17.3
Change in Other Noncurrent Liabilities	10.4	34.1
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(34.7)	(82.0)
Fuel, Materials and Supplies	8.7	29.1
Accounts Payable	46.2	(5.2)
Accrued Taxes, Net	41.3	82.7
Other Current Assets	(7.7)	9.8
Other Current Liabilities	(34.0)	(37.9)
Net Cash Flows from (Used for) Operating Activities	217.5	(280.6)
Investing Activities
Construction Expenditures	(247.0)	(182.5)
Change in Advances to Affiliates, Net	153.8	(27.6)
Acquisitions of Assets	658.0	147.1
Other Investing Activities	3.2	1.0
Net Cash Flows from (Used for) Investing Activities	(748.0)	(356.2)
Financing Activities
Capital Contributions from Parent	352.2	175.0
Issuance of Long-term Debt	0.0	496.4
Change in Short-term Debt with Original Maturities less than 90 Days, Net	0.0	(35.0)
Change in Advances from Affiliates, Net	213.2	25.0
Retirement of Long-term Debt	(3.1)	(3.1)
Principal Payments for Finance Leases Obligations	(5.4)	(5.4)
Dividends Paid on Common Stock	(12.5)	0.0
Dividends Paid on Common Stock	(1.5)	(1.6)
Other Financing Activities	0.1	0.3
Net Cash Flows from (Used for) Financing Activities	543.0	651.6
Net Increase (Decrease) in Cash and Cash Equivalents	12.5	14.8
Cash and Cash Equivalents at Beginning of Period	51.2	13.2
Cash and Cash Equivalents at End of Period	63.7	28.0
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	63.6	55.6
Net Cash Paid (Received) for Income Taxes	20.1	(12.8)
Noncash Acquisitions Under Finance Leases	2.8	3.2
Construction Expenditures Included in Current Liabilities as of March 31,	63.3	41.9
Noncontrolling Interest [Member]
Supplementary Information
Noncontrolling Interest Assumed - Dry Lake Solar Project	$ 0.0	$ 33.4