Acquisitions and Dispositions (Details)		3 Months Ended		9 Months Ended
		Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) MW	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Accounts Receivable and Accrued Unbilled Revenues				$ 976,800,000		$ 1,145,100,000
Net Property, Plant and Equipment				75,821,100,000		73,339,100,000
Accounts Payable, Current				2,258,600,000		2,670,800,000
Asset Retirement Obligation	[1],[2],[3],[4],[5],[6]			2,959,500,000		2,944,900,000
Proceeds from Sale of Property, Plant, and Equipment				1,335,600,000	$ 215,700,000
North Central Wind Energy Facilities
Payments to Acquire Property, Plant, and Equipment				2,000,000,000
Transmission Operations [Member]
Enterprise Value				2,850,000,000
Transmission Operations [Member] | Proceeds for KY Operations
Enterprise Value				2,646,000,000
Generation And Marketing [Member] | Proceeds of Mineral Rights Sale
Proceeds from Sale of Property, Plant, and Equipment			$ 120,000,000
Gain (Loss) on Disposition of Other Assets			116,000,000
Generation And Marketing [Member] | BP Wind Energy
Impairment of Equity Method Investment		$ 2,000,000	$ 186,000,000
Generation And Marketing [Member] | Competitive Contracted Renewables
Proceeds from Sale of Productive Assets				1,200,000,000
Gain (Loss) on Disposition of Business				112,000,000
gain (loss) on Disposition of Business net of Tax				88,000,000
Vertically Integrated Utilities [Member]
Enterprise Value				2,850,000,000
Pretax Reduction in Investment Basis				335,000,000
Vertically Integrated Utilities [Member] | Proceeds for KY Operations
Enterprise Value				$ 2,646,000,000
Vertically Integrated Utilities [Member] | Sundance [Member]
Wind Generation MWs | MW				199
Vertically Integrated Utilities [Member] | Maverick [Member]
Wind Generation MWs | MW				287
Vertically Integrated Utilities [Member] | Traverse [Member]
Wind Generation MWs | MW				998
Vertically Integrated Utilities [Member] | Traverse [Member] | North Central Wind Energy Facilities
Payments to Acquire Property, Plant, and Equipment				$ 1,200,000,000
Vertically Integrated Utilities [Member] | North Central Wind Energy Facilities
Wind Generation MWs | MW				1,484
Public Service Co Of Oklahoma [Member]
Percentage of an Asset Acquired				45.50%
Payments to Acquire Property, Plant, and Equipment				$ 146,000,000
Accounts Receivable and Accrued Unbilled Revenues				78,800,000		70,100,000
Net Property, Plant and Equipment				6,025,100,000		5,626,500,000
Accounts Payable, Current				$ 233,300,000		202,900,000
Southwestern Electric Power Co [Member]
Percentage of an Asset Acquired				54.50%
Payments to Acquire Property, Plant, and Equipment				$ 0	$ 658,000,000.0
Accounts Receivable and Accrued Unbilled Revenues				32,900,000		38,800,000
Net Property, Plant and Equipment				8,562,500,000		8,262,200,000
Accounts Payable, Current				232,100,000		213,100,000
Asset Retirement Obligation	[1],[3],[4],[5]			261,800,000		282,200,000
AEP Transmission Co [Member]
Accounts Receivable and Accrued Unbilled Revenues				80,400,000		46,900,000
Net Property, Plant and Equipment				14,318,900,000		13,339,900,000
Accounts Payable, Current				$ 336,100,000		$ 427,800,000

[1] In 2023, SWEPCo settled $35 million of costs related to closure/reclamation work performed due to the recent retirements of the Pirkey Plant and Dolet Hills Power Station. See “Coal-Fired Generation Plants” section of Note 4 for additional information.

[2] In August 2023, AEP completed the sale of its competitive contracted renewables portfolio to a nonaffiliated party and settled ARO liabilities of $31 million. See “Disposition of the Competitive Contracted Renewables Portfolio” section of Note 6 for additional information

[3] Includes ARO related to Sabine and DHLC.

[4] Includes ARO related to asbestos removal.

[5] Includes ARO related to ash disposal facilities.

[6] Includes ARO related to nuclear decommissioning costs for the Cook Plant of $2.05 billion and $2 billion as of September 30, 2023 and December 31, 2022, respectively.