Rate Matters West Companies (Details) $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) MW	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Public Utilities, General Disclosures [Line Items]
Other Asset Impairment Charges		$ 85.6	$ 48.8	$ 11.6
Net Investment		76,693.4	73,339.1
Noncurrent Regulatory Assets		5,092.4	4,762.0
AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		12,774.0	11,681.6
Noncurrent Regulatory Assets		315.3	298.3
Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Net Investment		6,112.3	5,626.5
Noncurrent Regulatory Assets		522.7	653.7
Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Other Asset Impairment Charges		85.6	0.0	11.6
Provision for Refund		(34.8)	(5.6)	$ (0.4)
Net Investment		8,558.4	8,262.2
Noncurrent Regulatory Assets		1,131.8	1,042.4
AEP Texas Interim Transmission and Distribution Rates [Member] | AEP Texas Inc. [Member]
Public Utilities, General Disclosures [Line Items]
AEP Texas Cumulative Revenues Subject to Review		$ 987.0
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		$ 1,700.0
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
Estimated Reduced Annual Revenues		$ 15.0
2016 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity		10.00%
Approved Return on Common Equity		9.60%
Requested Net Increase in Texas Annual Revenues		$ 69.0
Approved Net Increase in Texas Annual Revenues		50.0
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
2020 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Requested Annual Increase		$ 105.0
Approved Return on Common Equity		9.25%
Impairment Charge Total		$ 12.0
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
2020 Louisiana Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Requested Annual Increase		$ 134.0
Approved Return on Common Equity		9.50%
Requested Return on Equity		10.35%
Revised Requested Annual Increase		$ 95.0
Approved Annual Revenue Increase		27.0
Authorized Annual Base Rate Increase		21.0
Approved Rider to Recover Dolet Hils and Pirkey Costs		14.0
Reduction in Fuel Costs		8.0
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets		253.3	329.0
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member] | Louisiana Jurisdiction [Member]
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets		97.2	121.7
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member] | Arkansas
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets		$ 54.2	74.9
Remaining Recovery Period		6 years
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member] | Texas
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets		$ 101.9	$ 132.4
Approved Carrying Charge		1.65%
Remaining Recovery Period		5 years
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
2022 Oklahoma Base Rate Case [Member] | Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Approved Return on Common Equity		9.30%
Amount of Increase Related to Annual Depreciation Expense		$ 47.0
Requested Debt Capital Structure		45.40%
Requested Equity Capital Structure		54.60%
Requested Net Increase in Oklahoma Annual Revenues		$ 173.0
Amount of Increase Related to Annual Amortization Expense		16.0
Requested Net Increase in Oklahoma Annual Revenues Net of Rider Revenues		294.0
Approved Net Increase in Oklahoma Annual Revenues		131.0
Rock Falls Wind Facility Excess Benefits Rider		$ 21.0
2022 Oklahoma Base Rate Case [Member] | Public Service Co Of Oklahoma [Member] | Rock Falls [Member]
Public Utilities, General Disclosures [Line Items]
WindGenerationMWs | MW		155
2022 Oklahoma Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Requested Return on Equity		10.40%
Minimum [Member] | 2012 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Estimated Turk AFUDC Refunds		$ 0.0
Maximum [Member] | 2012 Texas Base Rate Case [Member] | Southwestern Electric Power Co [Member]
Public Utilities, General Disclosures [Line Items]
Estimated Turk AFUDC Refunds		$ 200.0
Subsequent Event [Member] | 2022 Oklahoma Base Rate Case [Member] | Public Service Co Of Oklahoma [Member]
Public Utilities, General Disclosures [Line Items]
Interim Rate Over Collection Refund	$ 18.0
Subsequent Event [Member] | 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