Rate Matters Regulated Operations (Details) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2022	Dec. 31, 2021
Public Utilities, General Disclosures [Line Items]
Net Investment		$ 68,708.2	$ 66,001.3
Regulatory Assets, Noncurrent		4,157.7	4,142.3
Regulatory Assets, Current		1,324.8	647.8
AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		11,055.3	10,635.4
Regulatory Assets, Noncurrent		269.4	275.2
AEP Transmission Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		12,449.2	11,935.7
Regulatory Assets, Noncurrent		4.6	8.5
Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		11,988.3	11,804.3
Regulatory Assets, Noncurrent		771.8	757.6
Regulatory Assets, Current		513.4	201.3
Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		7,349.4	7,310.9
Regulatory Assets, Noncurrent		428.8	410.9
Regulatory Assets, Current		22.3	6.4
Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		8,214.8	7,963.0
Regulatory Assets, Noncurrent		290.3	293.0
Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		5,455.0	4,802.8
Regulatory Assets, Noncurrent		1,043.8	1,037.4
Regulatory Assets, Current		314.5	194.6
Public Service Co Of Oklahoma [Member] | Northeastern Plant, Unit 3 | Generating Units Probable of Abandonment [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		151.3
Accelerated Depreciation Regulatory Asset		136.9
Cost of Removal Regulatory Liability	[1]	$ 20.2
Expected Retirement Date	[2]	2026
Depreciation	[3]	$ 14.9
Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		8,105.1	7,400.1
Regulatory Assets, Noncurrent		987.2	1,005.3
Net Under-Recovered Fuel Costs		187.0
Regulatory Assets, Current		286.3	143.9
Southwestern Electric Power Co [Member] | Dolet Hills Power Station and Related Fuel Operations
Public Utilities, General Disclosures [Line Items]
Share of Net Investment in Dolet Hills Power Station		113.0
Southwestern Electric Power Co [Member] | Dolet Hills Power Station and Related Fuel Operations | Arkansas
Public Utilities, General Disclosures [Line Items]
Recovery of 2021 Dolet Hills Fuel Costs		20.0
Southwestern Electric Power Co [Member] | Dolet Hills Power Station and Related Fuel Operations | Louisiana Jurisdiction [Member]
Public Utilities, General Disclosures [Line Items]
Recovery of 2021 Dolet Hills Fuel Costs		20.0
Approved Deferral of Dolet Hills Fuel Costs		30.0
Southwestern Electric Power Co [Member] | Pirkey Power Plant and Related Fuel Operations
Public Utilities, General Disclosures [Line Items]
Share of Net Investment in Pirkey Power Plant		204.0
Pirkey Power Plant and Sabine Unbilled Fixed Costs		79.0
Southwestern Electric Power Co [Member] | Pirkey Generating Station (Unit No. 1) | Generating Units Probable of Abandonment [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		75.1
Accelerated Depreciation Regulatory Asset		129.3
Cost of Removal Regulatory Liability		$ 39.5
Expected Retirement Date	[4]	2023
Depreciation	[3]	$ 13.2
Southwestern Electric Power Co [Member] | Welsh Plant Unit 1 and 3 | Generating Units Probable of Abandonment [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		449.4
Accelerated Depreciation Regulatory Asset		65.9
Cost of Removal Regulatory Liability	[5]	$ 58.8
Expected Retirement Date	[6]	2028
Depreciation	[3]	$ 38.4
Southwestern Electric Power Co [Member] | Welsh Plant Unit 2
Public Utilities, General Disclosures [Line Items]
Impairment Charge Welsh Plant, Unit 2		7.0
Southwestern Electric Power Co [Member] | Dolet Hills Power Station | Arkansas
Public Utilities, General Disclosures [Line Items]
Other Asset Impairment Charges		2.0
Southwestern Electric Power Co [Member] | Dolet Hills Power Station | Texas
Public Utilities, General Disclosures [Line Items]
Other Asset Impairment Charges		12.0
Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		879.6	1,048.6
Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		51.7	41.2
Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		146.3	105.1
Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		1.7	3.7
Regulatory Assets Pending Final Regulatory Approval [Member] | Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		25.1	3.8
Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		20.5	14.2
Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		631.7	880.6
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Plant Retirement Costs - Unrecovered Plant [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		35.2	35.2
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Dolet Hills Power Station Accelerated Depreciation [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		52.8	72.3
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Other Regulatory Assets Not Yet Being Recovered [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		14.7	9.2
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | February 2021 Severe Storm Fuel Costs
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[7]	133.7	430.2
Regulatory Assets, Current		37.0	63.0
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Pirkey Power Plant Accelerated Depreciation
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		129.3	87.0
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Welsh Unit 1 and 3 Accelerated Depreciation
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		65.9	45.9
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Dolet Hills Power Station Fuel Costs - Louisiana
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		31.5	30.9
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] | Mobile Generation Lease Payments
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		4.1	0.0
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] | COVID-19 - Virginia
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		6.9	6.8
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] | Other Regulatory Assets Not Yet Being Recovered [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		0.1	0.1
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Dolet Hills Power Station Accelerated Depreciation [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		52.8	72.3
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Plant Retirement Costs - Unrecovered Plant, Louisiana
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		35.2	35.2
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Other Regulatory Assets Not Yet Being Recovered [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		3.5	2.4
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | February 2021 Severe Storm Fuel Costs
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[8]	133.7	430.2
Regulatory Assets, Current		37.0	63.0
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Pirkey Power Plant Accelerated Depreciation
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		129.3	87.0
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Welsh Unit 1 and 3 Accelerated Depreciation
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		65.9	45.9
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Dolet Hills Power Station Fuel Costs - Louisiana
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		31.5	30.9
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Dolet Hills Power Station
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		53.0
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | COVID-19
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		11.5	11.2
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Plant Retirement Costs - Asset Retirement Obligation Costs [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		25.9	25.9
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Storm Related Costs [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		322.3	256.9
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Other Regulatory Assets Not Yet Being Recovered [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		42.8	41.8
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Renewable Energy Portfolio Standards Costs
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		14.0	2.1
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] | COVID-19
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		3.7	2.1
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] | Storm Related Costs [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		26.5	22.4
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] | Other Regulatory Assets Not Yet Being Recovered [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		8.1	7.4
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] | Texas Retail Electric Provider Bad Debt Expense
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		4.1	4.1
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] | Vegetation Management Programs
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		5.2	5.2
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] | Plant Retirement Costs - Asset Retirement Obligation Costs [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		25.9	25.9
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] | Storm Related Costs [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		97.4	68.8
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] | Other Regulatory Assets Not Yet Being Recovered [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		2.1	1.5
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] | Renewable Energy Portfolio Standards Costs
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		14.0	2.1
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] | COVID-19
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		0.1	1.7
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] | Other Regulatory Assets Not Yet Being Recovered [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		1.5	1.9
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Ohio Power Co [Member] | Storm Related Costs [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		25.1	3.8
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member] | Storm Related Costs [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		20.4	13.9
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member] | Other Regulatory Assets Not Yet Being Recovered [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		0.1	0.3
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Asset Retirement Obligation - Louisiana [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		11.0	10.3
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Other Regulatory Assets Not Yet Being Recovered [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		17.5	18.4
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Storm Related Costs - Louisiana
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		$ 151.3	$ 148.0

[1] Includes Northeastern Plant, Unit 4, which was retired in 2016. Removal of Northeastern Plant, Unit 4, will be performed with Northeastern Plant, Unit 3, after retirement.

[2] Northeastern Plant, Unit 3 is currently being recovered through 2040.

[3] Represents the amount of annual depreciation that has been collected from customers over the prior 12-month period.

[4] Pirkey Power Plant is currently being recovered through 2025 in the Louisiana jurisdiction and through 2045 in the Arkansas and Texas jurisdictions

[5] Includes Welsh Plant, Unit 2, which was retired in 2016. Removal of Welsh Plant, Unit 2, will be performed with Welsh Plant, Units 1 and 3, after retirement.

[6] Unit 1 is being recovered through 2027 in the Louisiana jurisdiction and through 2037 in the Arkansas and Texas jurisdictions. Unit 3 is being recovered through 2032 in the Louisiana jurisdiction and through 2042 in the Arkansas and Texas jurisdictions.

[7] Includes $37 million and $63 million of unrecovered winter storm fuel costs recorded as a current regulatory asset as of June 30, 2022 and December 31, 2021, respectively.

[8] Includes $37 million and $63 million of unrecovered winter storm fuel costs recorded as a current regulatory asset as of June 30, 2022 and December 31, 2021, respectively.