Rate Matters Regulated Operations (Details) - USD ($) $ in Millions		9 Months Ended
		Sep. 30, 2023		Sep. 30, 2022	Dec. 31, 2022
Public Utilities, General Disclosures [Line Items]
Net Investment		$ 75,821.1			$ 73,339.1
Regulatory Assets, Noncurrent		4,607.3			4,762.0
Other Asset Impairment Charges		0.0		$ 24.9
Regulatory Assets, Current		1,087.6			1,310.0
AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		12,590.8			11,681.6
Regulatory Assets, Noncurrent		307.7			298.3
AEP Transmission Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		14,318.9			13,339.9
Regulatory Assets, Noncurrent		4.4			7.2
Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		12,825.1			12,379.2
Regulatory Assets, Noncurrent		978.8			1,058.6
Other Asset Impairment Charges		0.0		$ 24.9
Regulatory Assets, Current		442.0			473.1
Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		7,535.7			7,411.5
Regulatory Assets, Noncurrent		377.7			459.6
Regulatory Assets, Current		13.3			47.1
Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		9,160.0			8,609.3
Regulatory Assets, Noncurrent		413.2			327.3
Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		6,025.1			5,626.5
Regulatory Assets, Noncurrent		477.2			653.7
Regulatory Assets, Current		168.2			178.7
Public Service Co Of Oklahoma [Member] | Northeastern Plant, Unit 3 | Generating Units Probable of Abandonment [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		112.5
Accelerated Depreciation Regulatory Asset		159.5
Cost of Removal Regulatory Liability	[1]	$ 20.4
Expected Retirement Date	[2]	2026
Depreciation	[3]	$ 15.0
Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		8,562.5			8,262.2
Regulatory Assets, Noncurrent		1,116.9			1,042.4
Net Under-Recovered Fuel Costs		91.0
Regulatory Assets, Current		184.4			353.0
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		105.0
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		35.0
Recommended Disallowance from Staff or Intervenors		72.0
Southwestern Electric Power Co [Member] | Dolet Hills Power Station and Related Fuel Operations | Texas
Public Utilities, General Disclosures [Line Items]
Oxbow Mine Related Costs Recovery Request		48.0
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		180.0
Southwestern Electric Power Co [Member] | Pirkey Power Plant and Related Fuel Operations | Texas
Public Utilities, General Disclosures [Line Items]
Oxbow Mine Related Costs Recovery Request		33.0
Southwestern Electric Power Co [Member] | Pirkey Generating Station (Unit No. 1) | Texas
Public Utilities, General Disclosures [Line Items]
Net Investment		66.0
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		368.8
Accelerated Depreciation Regulatory Asset		115.5
Cost of Removal Regulatory Liability	[4]	$ 58.0
Expected Retirement Date	[5],[6]	2028
Depreciation	[3]	$ 38.6
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		886.3			919.3
Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		61.5			67.0
Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		148.4			144.5
Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		32.3			23.7
Regulatory Assets Pending Final Regulatory Approval [Member] | Ohio Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		21.2			33.8
Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		93.0			25.6
Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		446.5			547.3
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		21.0			19.3
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]	101.4			121.7
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		113.0			116.5
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		115.5			85.6
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		34.7			32.0
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Mobile Generation Lease Payments
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent	[8]	0.0			17.6
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	[9]	0.0			17.6
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		7.0			7.0
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		0.2			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		12.0			9.7
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		1.7			2.5
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	[10]	101.4			121.7
Regulatory Assets, Current		37.0			37.0
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		113.0			116.5
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		115.5			85.6
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		34.7			32.0
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	[11],[13]	385.8	[12]		407.2
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		51.6			55.6
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | 2020-2022 Virginia Triennial Review [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		37.4			37.9
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		35.9			26.7
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		16.3			13.4
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		72.2			72.6
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		5.9			1.1
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] | 2020-2022 Virginia Triennial Review [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		37.4			37.9
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] | Storm Related Costs [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		29.4			21.6
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		2.7			2.0
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	[14]	21.2			33.8
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Ohio Power Co [Member] | Storm-Related Costs Recovery Request [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		34.0
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		92.8	[15]		25.5
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		0.2			0.1
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member] | Storm-Related Costs Recovery Request [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		58.0
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Storm Related Costs [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		53.4	[16],[17]		151.5
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		0.0			11.8
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		14.8			$ 16.0
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Storm-Related Costs Recovery Request [Member] | Louisiana Jurisdiction [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		29.0
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] | Storm-Related Costs Recovery Request [Member] | Texas
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		$ 24.0

[1] Includes Northeastern Plant, Unit 4, which was retired in 2016. Removal of Northeastern Plant, Unit 4, will be performed with the removal of 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] Includes Welsh Plant, Unit 2, which was retired in 2016. Removal of Welsh Plant, Unit 2, will be performed with the removal of Welsh Plant, Units 1 and 3, after retirement.

[5] Represents projected retirement date of coal assets, units are being evaluated for conversion to natural gas after 2028.

[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 $37 million of unrecovered winter storm fuel costs recorded as a current regulatory asset as of September 30, 2023 and December 31, 2022, respectively. See the “February 2021 Severe Winter Weather Impacts in SPP” section below for additional information.

[8] In October 2023, the PUCT issued an order approving a rider to recover deferred Texas Mobile Generation Costs. Recovery of deferred costs through the new rider is updated annually, subject to Commission review.

[9] In October 2023, the PUCT issued an order approving a rider to recover deferred Texas Mobile Generation Costs. Recovery of deferred costs through the new rider is updated annually, subject to Commission review.

[10] Includes $37 million and $37 million of unrecovered winter storm fuel costs recorded as a current regulatory asset as of September 30, 2023 and December 31, 2022, respectively. See the “February 2021 Severe Winter Weather Impacts in SPP” section below for additional information.

[11] In April 2023, the LPSC issued an order approving the prudence and future recovery of the Louisiana storm-related regulatory assets. See “2021 Louisiana Storm Cost Filing” section below for additional information.

[12] In June 2023, storms in the Oklahoma, Louisiana and Texas service territories caused power outages and extensive damage resulting in the deferral of $58 million, $29 million and $24 million, respectively. Recovery of these storm costs will be addressed in a future request.

[13] In October 2023, the PUCO issued an order approving recovery of $34 million in Ohio storm-related costs.

[14] In October 2023, the PUCO issued an order approving recovery of $34 million in storm-related costs.

[15] In June 2023, storms caused power outages and extensive damage to the Oklahoma service territory, resulting in the deferral of $58 million. Recovery for these storm costs will be addressed in a future request.

[16] In April 2023, the LPSC issued an order approving the prudence and future recovery of the Louisiana storm-related regulatory assets. See “2021 Louisiana Storm Cost Filing” section below for additional information.

[17] In June 2023, additional storms in the Louisiana and Texas service territories caused power outages and extensive damage resulting in the deferral of $29 million and $24 million, respectively. Recovery of these storm costs will be addressed in a future request.