Rate Matters West Companies (Details) $ in Millions	1 Months Ended	9 Months Ended
	Oct. 31, 2024 USD ($)	Sep. 30, 2024 USD ($) MW	Dec. 31, 2023 USD ($)
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		$ 5,318.9	$ 5,092.4
Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		1,283.6	874.4
Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		524.9	522.7
Public Service Co Of Oklahoma [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		111.6	88.7
Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		1,120.3	1,131.8
Southwestern Electric Power Co [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		477.8	444.9
AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		354.0	315.3
AEP Texas Inc. [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		65.1	64.3
Indiana Michigan Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		572.6	406.3
Indiana Michigan Power Co [Member] | Regulatory Assets Pending Final Regulatory Approval [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		$ 111.6	33.2
ETT Interim Transmission Rates [Member]
Public Utilities, General Disclosures [Line Items]
Parent Ownership Interest In ETT		50.00%
AEP Share Of ETT Cumulative Revenues Subject To Review		$ 1,800.0
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		195.6	253.3
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member] | Arkansas
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		$ 40.4	54.2
Remaining Recovery Period		6 years
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member] | Louisiana Jurisdiction [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		$ 75.9	97.2
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member] | Texas
Public Utilities, General Disclosures [Line Items]
Regulatory Assets, Noncurrent		$ 79.3	$ 101.9
Approved Carrying Charge		1.65%
Remaining Recovery Period		5 years
2012 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
2013 Reversal Of Previously Recorded Regulatory Disallowances		$ 114.0
Turk AFUDC Disallowance		86.0
Revenue Refund Provision		160.0
2012 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member] | Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Turk AFUDC Refund	$ 148.0
2012 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member] | Minimum Net Actuarial Loss [Member]
Public Utilities, General Disclosures [Line Items]
Recommended Customer Refunds		$ 149.0
Recommended Refund Period		18 months
2012 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member] | Maximum Net Actuarial Loss [Member]
Public Utilities, General Disclosures [Line Items]
Recommended Customer Refunds		$ 197.0
Recommended Refund Period		48 months
2016 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Requested Net Increase in Texas Annual Revenues		$ 69.0
Approved Net Increase in Texas Annual Revenues		$ 50.0
Approved Return on Common Equity		9.60%
Approved Additional Vegetation Management Expenses		$ 2.0
Impairment Charge Total		19.0
Impairment Charge Welsh Plant, Unit 2		7.0
Impairment Charge Disallowed Plant Investments		12.0
Additional Revenues Recognized to be Surcharged to Customers		32.0
Additional Recognized Expenses Consisting Primarily of Depreciation and Vegetation Management		$ 7.0
Requested Return on Equity		10.00%
2020 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Approved Return on Common Equity		9.25%
Impairment Charge Total		$ 12.0
Requested Annual Increase		$ 105.0
Requested Return on Equity		10.35%
Requested Net Annual Increase		$ 90.0
Revised Requested Annual Increase		100.0
Revised Requested Net Annual Increase		85.0
Approved Annual Revenue Increase		39.0
Amount of Approved Increase Related to Vegetation Management		5.0
Amount of Approved Increase Related to Storm Catastrophe Reserve		$ 2.0
2021 Louisiana Storm Cost Filing | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Interim WACC		3.125%
Approved Deferred Storm Costs		$ 150.0
Approved Securitization		343.0
Securitization Storm Costs		180.0
Securitization Storm Reserve		$ 150.0
2024 AEP Texas Base Rate Case [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity		10.60%
Requested Debt Capital Structure		55.00%
Requested Equity Capital Structure		45.00%
Requested Annual Base Rate Increase		$ 164.0
AEP Texas Cumulative Revenues Subject to Reconciliation		$ 1,300.0
2024 AEP Texas Base Rate Case [Member] | AEP Texas Inc. [Member] | Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Approved Return on Common Equity	9.76%
Approved Annual Revenue Increase	$ 70.0
Approved Debt Capital Structure	57.50%
Approved Equity Capital Structure	42.50%
2024 Oklahoma Base Rate Case [Member] | Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity		10.80%
Requested Debt Capital Structure		48.90%
Requested Equity Capital Structure		51.10%
Requested Net Increase in Oklahoma Annual Revenues		$ 218.0
Wind Generation MWs | MW		155
OCC Staff Recommended Annual Base Rate Increase		$ 115.0
OCC Staff Recommended Return on Equity		9.30%
OCC Staff Recommended Capital Investment Disallowance		$ 62.0
2024 Oklahoma Base Rate Case [Member] | Public Service Co Of Oklahoma [Member] | Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Settlement Agreement Annual Increase	$ 120.0
Settlement Agreement Return on Common Equity	9.50%
Settlement Agreement Debt Capital Structure	48.90%
Settlement Agreement Equity Capital Structure	51.10%
Interim Annual Base Rate Increase	$ 120.0
2024 Oklahoma Base Rate Case [Member] | Public Service Co Of Oklahoma [Member] | Minimum Net Actuarial Loss [Member]
Public Utilities, General Disclosures [Line Items]
Intervenor Recommended Annual Base Rate Increase		$ 19.0
Intervenor Recommended Return on Equity		9.00%
2024 Oklahoma Base Rate Case [Member] | Public Service Co Of Oklahoma [Member] | Maximum Net Actuarial Loss [Member]
Public Utilities, General Disclosures [Line Items]
Intervenor Recommended Annual Base Rate Increase		$ 113.0
Intervenor Recommended Return on Equity		9.60%