Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating Activities
Net Income (Loss)	$ 400.4	$ 718.1
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	775.5	792.4
Deferred Income Taxes	68.0	(17.7)
Allowance for Equity Funds Used During Construction	(31.3)	(31.0)
Mark-to-Market of Risk Management Contracts	(82.0)	282.3
Property Taxes	(101.6)	(82.0)
Deferred Fuel Over/Under-Recovery, Net	128.0	(148.8)
Change in Other Noncurrent Assets	(96.0)	49.4
Change in Other Noncurrent Liabilities	(58.7)	36.9
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	348.4	(24.3)
Fuel, Materials and Supplies	(115.9)	27.6
Accounts Payable	(255.9)	(1.0)
Accrued Taxes, Net	(150.9)	(51.8)
Other Current Assets	(94.6)	133.9
Other Current Liabilities	(127.6)	(61.8)
Net Cash Flows from (Used for) Operating Activities	717.8	1,622.2
Investing Activities
Construction Expenditures	(2,090.1)	(1,686.6)
Purchases of Investment Securities	(537.3)	(508.5)
Sales of Investment Securities	517.6	497.4
Acquisitions of Nuclear Fuel	(1.7)	(31.1)
Other Investing Activities	12.0	42.9
Net Cash Flows from (Used for) Investing Activities	(2,245.2)	(2,893.2)
Financing Activities
Issuance of Common Stock	41.1	809.5
Issuance of Long-term Debt	2,847.3	499.6
Issuance of Short-term Debt with Original Maturities greater than 90 Days	97.4	271.0
Change in Short-term Debt with Original Maturities less than 90 Days, Net	(433.7)	710.3
Retirement of Long-term Debt	(519.5)	(51.0)
Redemption of Short-term Debt with Original Maturities Greater than 90 Days	(153.8)	(215.0)
Principal Payments for Finance Leases Obligations	(26.8)	(14.7)
Dividends Paid on Common Stock	(431.8)	(398.8)
Other Financing Activities	(55.8)	(65.8)
Net Cash Flows from (Used for) Financing Activities	1,364.4	1,545.1
Net Increase (Decrease) in Cash and Cash Equivalents	(163.0)	274.1
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	556.5	451.4
Cash and Cash Equivalents at Beginning of Period	509.4
Cash, Cash Equivalents and Restricted Cash at End of Period	393.5	725.5
Cash and Cash Equivalents at End of Period	343.5
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	311.9	233.9
Net Cash Paid (Received) for Income Taxes	15.8	6.9
Noncash Acquisitions Under Finance Leases	12.5	7.2
Construction Expenditures Included in Current Liabilities as of March 31,	1,076.1	758.6
Forward Equity Purchase Contract Included in Current and Noncurrent Liabilities as of September 30,	12.5	16.7
Commitment from Bank Conduits to Finance Receivables	125.0
Commitment from Bank Conduits to Finance Receivables Two	$ 625.0
2020 Equity Units [Member] | Maximum [Member]
Supplementary Information
AEP Share Price for Equity Unit Conversion	$ 99.95
Retained Earnings [Member]
Supplementary Information
Forward Equity Purchase Contract Included in Current and Noncurrent Liabilities as of September 30,		1.5
Competitive Contracted Renewable Portfolio
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Loss on the Expected Sale of the Competitive Contracted Renewable Portfolio	$ 112.0	0.0
Renewable Energy Facilities
Investing Activities
Acquisitions of Assets	(145.7)	(1,207.3)
AEP Texas Inc. [Member]
Operating Activities
Net Income (Loss)	47.6	69.6
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	111.0	108.8
Deferred Income Taxes	6.4	7.0
Allowance for Equity Funds Used During Construction	(6.3)	(4.3)
Mark-to-Market of Risk Management Contracts	0.4	(0.2)
Property Taxes	(88.8)	(79.5)
Change in Other Noncurrent Assets	(18.3)	(17.0)
Change in Other Noncurrent Liabilities	(0.8)	5.8
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	24.6	(20.2)
Fuel, Materials and Supplies	(1.1)	(4.9)
Accounts Payable	3.6	9.6
Accrued Taxes, Net	44.5	37.9
Other Current Assets	0.9	0.8
Other Current Liabilities	13.0	16.5
Net Cash Flows from (Used for) Operating Activities	136.7	129.9
Investing Activities
Construction Expenditures	(450.4)	(356.6)
Change in Advances to Affiliates, Net	0.1	0.1
Other Investing Activities	7.3	13.7
Net Cash Flows from (Used for) Investing Activities	(443.0)	(342.8)
Financing Activities
Capital Contributions from Parent	100.0	0.0
Change in Advances from Affiliates, Net	354.3	235.3
Retirement of Long-term Debt	(136.7)	(11.4)
Principal Payments for Finance Leases Obligations	(1.8)	(1.7)
Other Financing Activities	0.3	0.2
Net Cash Flows from (Used for) Financing Activities	316.1	222.4
Net Increase (Decrease) in Cash and Cash Equivalents	9.8	9.5
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	32.8	30.5
Cash and Cash Equivalents at Beginning of Period	0.1
Cash, Cash Equivalents and Restricted Cash at End of Period	42.6	40.0
Cash and Cash Equivalents at End of Period	0.1
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	31.6	29.9
Noncash Acquisitions Under Finance Leases	1.8	0.6
Construction Expenditures Included in Current Liabilities as of March 31,	177.5	147.6
AEP Texas Inc. [Member] | Retained Earnings [Member]
Operating Activities
Net Income (Loss)	47.6	69.6
AEP Transmission Co [Member]
Operating Activities
Net Income (Loss)	162.7	155.4
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	95.2	83.1
Deferred Income Taxes	20.6	23.1
Allowance for Equity Funds Used During Construction	(16.4)	(15.6)
Property Taxes	34.6	31.3
Provision for Refund Affiliated	4.8	0.3
Change in Other Noncurrent Assets	0.9	2.1
Change in Other Noncurrent Liabilities	6.6	11.8
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(12.5)	(21.8)
Fuel, Materials and Supplies	(4.1)	(0.8)
Accounts Payable	41.0	3.6
Accrued Taxes, Net	(59.9)	(53.7)
Other Current Assets	1.0	0.5
Other Current Liabilities	29.6	19.8
Net Cash Flows from (Used for) Operating Activities	299.3	238.8
Investing Activities
Construction Expenditures	(439.7)	(417.1)
Change in Advances to Affiliates, Net	(293.1)	22.6
Other Investing Activities	(0.8)	(1.7)
Net Cash Flows from (Used for) Investing Activities	(733.6)	(396.2)
Financing Activities
Capital Contributions from Parent	25.0	0.0
Issuance of Long-term Debt	689.2	0.0
Change in Advances from Affiliates, Net	(224.9)	197.4
Dividends Paid on Common Stock	(55.0)	(40.0)
Net Cash Flows from (Used for) Financing Activities	434.3	157.4
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	16.2	16.4
Construction Expenditures Included in Current Liabilities as of March 31,	305.4	214.6
AEP Transmission Co [Member] | Retained Earnings [Member]
Operating Activities
Net Income (Loss)	162.7	155.4
Financing Activities
Dividends Paid on Common Stock	(55.0)	(40.0)
Appalachian Power Co [Member]
Operating Activities
Net Income (Loss)	112.5	120.2
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	143.0	145.2
Deferred Income Taxes	10.3	4.1
Allowance for Equity Funds Used During Construction	(2.4)	(2.0)
Mark-to-Market of Risk Management Contracts	60.1	34.3
Deferred Fuel Over/Under-Recovery, Net	26.0	(100.3)
Change in Other Noncurrent Assets	(5.5)	1.4
Change in Other Noncurrent Liabilities	(33.0)	(20.4)
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	54.5	72.4
Fuel, Materials and Supplies	(59.3)	19.5
Increase (Decrease) in Margin Deposits Outstanding	(11.1)	61.4
Accounts Payable	(156.1)	33.6
Accrued Taxes, Net	23.6	26.1
Other Current Assets	2.9	2.3
Other Current Liabilities	(1.2)	18.3
Net Cash Flows from (Used for) Operating Activities	164.3	416.1
Investing Activities
Construction Expenditures	(287.4)	(233.9)
Change in Advances to Affiliates, Net	1.1	1.1
Other Investing Activities	1.5	9.7
Net Cash Flows from (Used for) Investing Activities	(284.8)	(223.1)
Financing Activities
Change in Advances from Affiliates, Net	128.0	(163.8)
Retirement of Long-term Debt	(13.0)	(12.7)
Principal Payments for Finance Leases Obligations	(2.0)	(2.0)
Dividends Paid on Common Stock	0.0	(18.8)
Other Financing Activities	0.2	0.2
Net Cash Flows from (Used for) Financing Activities	113.2	(197.1)
Net Increase (Decrease) in Cash and Cash Equivalents	(7.3)	(4.1)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	21.9	20.1
Cash and Cash Equivalents at Beginning of Period	7.5
Cash, Cash Equivalents and Restricted Cash at End of Period	14.6	16.0
Cash and Cash Equivalents at End of Period	7.1
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	37.9	21.0
Noncash Acquisitions Under Finance Leases	0.6	0.3
Construction Expenditures Included in Current Liabilities as of March 31,	122.6	94.9
Appalachian Power Co [Member] | Retained Earnings [Member]
Operating Activities
Net Income (Loss)	112.5	120.2
Indiana Michigan Power Co [Member]
Operating Activities
Net Income (Loss)	102.8	89.5
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	125.2	134.9
Deferred Income Taxes	(3.3)	(11.5)
Amortization (Deferral) of Incremental Nuclear Refueling Outage Expenses, Net	18.1	(6.5)
Allowance for Equity Funds Used During Construction	(0.5)	(2.9)
Mark-to-Market of Risk Management Contracts	8.8	(2.8)
Amortization of Nuclear Fuel	25.0	22.9
Deferred Fuel Over/Under-Recovery, Net	3.8	6.1
Change in Other Noncurrent Assets	(4.3)	(5.2)
Change in Other Noncurrent Liabilities	3.7	2.4
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	52.7	25.9
Fuel, Materials and Supplies	(24.1)	6.3
Accounts Payable	(27.8)	3.8
Accrued Taxes, Net	21.1	22.3
Other Current Assets	(1.9)	15.3
Other Current Liabilities	(41.8)	(53.6)
Net Cash Flows from (Used for) Operating Activities	257.5	246.9
Investing Activities
Construction Expenditures	(141.7)	(129.9)
Change in Advances to Affiliates, Net	(37.0)	0.0
Purchases of Investment Securities	(536.3)	(507.7)
Sales of Investment Securities	517.6	493.5
Acquisitions of Nuclear Fuel	(1.7)	(31.1)
Other Investing Activities	3.3	0.3
Net Cash Flows from (Used for) Investing Activities	(195.8)	(174.9)
Financing Activities
Issuance of Long-term Debt	499.8	0.0
Change in Advances from Affiliates, Net	(249.9)	(19.7)
Retirement of Long-term Debt	(274.3)	(23.8)
Principal Payments for Finance Leases Obligations	(1.9)	(1.6)
Dividends Paid on Common Stock	(31.2)	(25.0)
Other Financing Activities	0.1	0.1
Net Cash Flows from (Used for) Financing Activities	(57.4)	(70.0)
Net Increase (Decrease) in Cash and Cash Equivalents	4.3	2.0
Cash and Cash Equivalents at Beginning of Period	4.2	1.3
Cash and Cash Equivalents at End of Period	8.5	3.3
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	44.4	41.6
Net Cash Paid (Received) for Income Taxes	2.4	0.0
Noncash Acquisitions Under Finance Leases	2.2	0.3
Construction Expenditures Included in Current Liabilities as of March 31,	61.3	60.7
Indiana Michigan Power Co [Member] | Retained Earnings [Member]
Operating Activities
Net Income (Loss)	102.8	89.5
Ohio Power Co [Member]
Operating Activities
Net Income (Loss)	78.0	83.2
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	75.2	74.9
Deferred Income Taxes	2.1	9.5
Carrying Costs Income	0.0	(0.1)
Allowance for Equity Funds Used During Construction	(2.8)	(3.0)
Mark-to-Market of Risk Management Contracts	7.2	(24.0)
Property Taxes	92.0	87.0
Change in Other Noncurrent Assets	(43.2)	(1.2)
Change in Other Noncurrent Liabilities	(21.7)	11.0
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	(20.3)	(28.8)
Fuel, Materials and Supplies	(4.8)	(5.0)
Accounts Payable	(5.5)	4.0
Increase (Decrease) in Contract with Customer, Liability	(22.7)	24.1
Accrued Taxes, Net	(157.9)	(158.3)
Other Current Assets	(2.2)	13.5
Other Current Liabilities	(7.7)	20.3
Net Cash Flows from (Used for) Operating Activities	(34.3)	107.2
Investing Activities
Construction Expenditures	(262.0)	(188.7)
Change in Advances to Affiliates, Net	0.0	42.0
Other Investing Activities	4.9	4.2
Net Cash Flows from (Used for) Investing Activities	(257.1)	(142.5)
Financing Activities
Capital Contributions from Parent	50.0	0.0
Change in Advances from Affiliates, Net	241.7	55.7
Principal Payments for Finance Leases Obligations	(1.2)	(1.2)
Dividends Paid on Common Stock	0.0	(15.0)
Other Financing Activities	0.4	0.2
Net Cash Flows from (Used for) Financing Activities	290.9	39.7
Net Increase (Decrease) in Cash and Cash Equivalents	(0.5)	4.4
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	9.6	3.0
Cash and Cash Equivalents at Beginning of Period	9.6
Cash, Cash Equivalents and Restricted Cash at End of Period	9.1	7.4
Cash and Cash Equivalents at End of Period	9.1
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	20.9	19.5
Noncash Acquisitions Under Finance Leases	0.6	0.6
Construction Expenditures Included in Current Liabilities as of March 31,	109.9	67.0
Ohio Power Co [Member] | Retained Earnings [Member]
Operating Activities
Net Income (Loss)	78.0	83.2
Public Service Co Of Oklahoma [Member]
Operating Activities
Net Income (Loss)	(2.3)	5.8
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	61.1	52.7
Deferred Income Taxes	12.2	(17.4)
Allowance for Equity Funds Used During Construction	(1.5)	(1.1)
Mark-to-Market of Risk Management Contracts	13.9	1.8
Property Taxes	(45.6)	(37.8)
Deferred Fuel Over/Under-Recovery, Net	49.4	(26.4)
Change in Other Noncurrent Assets	(9.7)	(3.9)
Change in Other Noncurrent Liabilities	1.4	6.2
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	27.2	11.5
Fuel, Materials and Supplies	12.9	0.0
Accounts Payable	(62.8)	(20.8)
Accrued Taxes, Net	24.9	45.2
Other Current Assets	0.4	1.9
Other Current Liabilities	(7.5)	(1.8)
Net Cash Flows from (Used for) Operating Activities	74.0	15.9
Investing Activities
Construction Expenditures	(146.8)	(104.1)
Acquisitions of Assets	(146.0)
Other Investing Activities	0.4	0.4
Net Cash Flows from (Used for) Investing Activities	(292.1)	(653.0)
Financing Activities
Issuance of Long-term Debt	469.9	500.0
Change in Advances from Affiliates, Net	(233.5)	139.5
Retirement of Long-term Debt	(0.1)	(0.1)
Principal Payments for Finance Leases Obligations	(0.8)	(0.8)
Dividends Paid on Common Stock	(17.5)	0.0
Other Financing Activities	(0.1)	0.1
Net Cash Flows from (Used for) Financing Activities	217.9	638.7
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(0.2)	1.6
Cash and Cash Equivalents at Beginning of Period	4.0	1.3
Cash and Cash Equivalents at End of Period	3.8	2.9
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	22.3	21.3
Noncash Acquisitions Under Finance Leases	0.2	0.3
Construction Expenditures Included in Current Liabilities as of March 31,	63.4	37.1
Public Service Co Of Oklahoma [Member] | Retained Earnings [Member]
Operating Activities
Net Income (Loss)	(2.3)	5.8
Public Service Co Of Oklahoma [Member] | Renewable Energy Facilities
Investing Activities
Acquisitions of Assets	(145.7)	(549.3)
Southwestern Electric Power Co [Member]
Operating Activities
Net Income (Loss)	41.8	45.1
Adjustments to Reconcile Net Income to Net Cash Flows from (Used for) Operating Activities:
Depreciation and Amortization	80.4	77.8
Deferred Income Taxes	10.8	(9.5)
Allowance for Equity Funds Used During Construction	(0.5)	(1.6)
Mark-to-Market of Risk Management Contracts	9.9	(7.0)
Property Taxes	(77.5)	(64.5)
Deferred Fuel Over/Under-Recovery, Net	42.9	9.2
Change in Other Noncurrent Assets	7.2	29.9
Change in Other Noncurrent Liabilities	(3.3)	16.7
Changes in Certain Components of Working Capital:
Accounts Receivable, Net	29.9	7.6
Fuel, Materials and Supplies	(4.3)	(0.6)
Accounts Payable	(47.8)	(35.1)
Accrued Taxes, Net	62.3	75.7
Other Current Assets	7.3	3.8
Other Current Liabilities	(48.9)	(56.7)
Net Cash Flows from (Used for) Operating Activities	110.2	90.8
Investing Activities
Construction Expenditures	(201.9)	(129.5)
Change in Advances to Affiliates, Net	0.0	153.8
Acquisitions of Assets	0.0	658.0
Other Investing Activities	0.4	1.9
Net Cash Flows from (Used for) Investing Activities	(201.5)	(631.8)
Financing Activities
Capital Contributions from Parent	50.0	350.0
Issuance of Long-term Debt	347.3	0.0
Change in Short-term Debt with Original Maturities less than 90 Days, Net	16.0	0.0
Change in Advances from Affiliates, Net	(291.9)	202.9
Retirement of Long-term Debt	(94.1)	(1.6)
Principal Payments for Finance Leases Obligations	(14.8)	(2.7)
Dividends Paid on Common Stock	(1.5)	(0.8)
Other Financing Activities	0.1	0.1
Net Cash Flows from (Used for) Financing Activities	11.1	547.9
Net Increase (Decrease) in Cash and Cash Equivalents	(80.2)	6.9
Cash and Cash Equivalents at Beginning of Period	88.4	51.2
Cash and Cash Equivalents at End of Period	8.2	58.1
Supplementary Information
Cash Paid for Interest, Net of Capitalized Amounts	45.3	37.7
Noncash Acquisitions Under Finance Leases	0.9	1.0
Construction Expenditures Included in Current Liabilities as of March 31,	$ 113.3	$ 47.8