Commitments, Guarantees and Contingencies (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Maximum Potential Loss [Abstract]
Max Potential Loss on Master Lease Agreements		$ 44,600		$ 44,600
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation	[1],[2],[3],[4],[5],[6]	3,713,300		3,713,300		$ 3,031,200
Property, Plant and Equipment		24,319,700		24,319,700		24,329,500
Regulatory Assets, Noncurrent		5,354,300		5,354,300		5,092,400
Utilities Operating Expense, Operations		817,300	$ 631,200	1,579,600	$ 1,311,200
Revised CCR Rule [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation		674,400		674,400
Property, Plant and Equipment	[7]	176,900		176,900
Regulatory Assets, Noncurrent	[8]	355,000		355,000
Utilities Operating Expense, Operations	[9]			142,500
Non-Registrants [Member] | Revised CCR Rule [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation		166,100		166,100
Property, Plant and Equipment	[7]	43,800		43,800
Regulatory Assets, Noncurrent	[8]	46,100		46,100
Utilities Operating Expense, Operations	[9]			76,200
AEP Texas Inc. [Member]
Maximum Potential Loss [Abstract]
Max Potential Loss on Master Lease Agreements		10,600		10,600
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation	[3],[4]	3,800		3,800		4,500
Regulatory Assets, Noncurrent		350,600		350,600		315,300
Utilities Operating Expense, Operations		147,800	93,900	288,600	240,800
AEP Transmission Co [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Regulatory Assets, Noncurrent		1,600		1,600		3,100
Utilities Operating Expense, Operations		40,000	26,400	69,900	55,400
Appalachian Power Co [Member]
Maximum Potential Loss [Abstract]
Max Potential Loss on Master Lease Agreements		5,900		5,900
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation	[3],[4]	778,800		778,800		464,000
Property, Plant and Equipment		7,192,800		7,192,800		7,041,300
Regulatory Assets, Noncurrent		1,324,900		1,324,900		1,155,100
Utilities Operating Expense, Operations		212,000	189,900	424,600	381,700
Appalachian Power Co [Member] | Revised CCR Rule [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation		312,200		312,200
Property, Plant and Equipment	[7]	75,600		75,600
Regulatory Assets, Noncurrent	[8]	236,600		236,600
Utilities Operating Expense, Operations				0
Indiana Michigan Power Co [Member]
Maximum Potential Loss [Abstract]
Max Potential Loss on Master Lease Agreements		4,200		4,200
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation	[3],[4],[5]	2,228,800		2,228,800		2,106,000
Property, Plant and Equipment		5,669,700		5,669,700		5,646,800
Regulatory Assets, Noncurrent		589,600		589,600		406,300
Utilities Operating Expense, Operations		190,300	170,100	368,500	339,800
Indiana Michigan Power Co [Member] | Revised CCR Rule [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation		85,700		85,700
Property, Plant and Equipment		0		0
Regulatory Assets, Noncurrent	[8]	72,300		72,300
Utilities Operating Expense, Operations	[9]			13,400
Ohio Power Co [Member]
Maximum Potential Loss [Abstract]
Max Potential Loss on Master Lease Agreements		7,000		7,000
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
HB6 Settlement Payment				450
Asset Retirement Obligation	[3],[4]	55,000		55,000		2,100
Regulatory Assets, Noncurrent		411,200		411,200		455,000
Utilities Operating Expense, Operations		283,800	265,400	577,000	539,200
Ohio Power Co [Member] | Revised CCR Rule [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation		52,900		52,900
Property, Plant and Equipment		0		0
Regulatory Assets, Noncurrent		0		0
Utilities Operating Expense, Operations	[9]			52,900
Public Service Co Of Oklahoma [Member]
Maximum Potential Loss [Abstract]
Max Potential Loss on Master Lease Agreements		4,400		4,400
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation	[1],[3],[4]	119,700		119,700		84,200
Property, Plant and Equipment		2,747,300		2,747,300		2,695,500
Regulatory Assets, Noncurrent		532,000		532,000		522,700
Utilities Operating Expense, Operations		119,300	87,500	215,900	179,600
Public Service Co Of Oklahoma [Member] | Revised CCR Rule [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation		33,700		33,700
Property, Plant and Equipment	[7]	33,700		33,700
Regulatory Assets, Noncurrent		0		0
Utilities Operating Expense, Operations				0
Southwestern Electric Power Co [Member]
Maximum Potential Loss [Abstract]
Max Potential Loss on Master Lease Agreements		5,100		5,100
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation	[1],[2],[3],[4]	272,300		272,300		281,600
Property, Plant and Equipment		4,818,900		4,818,900		4,790,700
Regulatory Assets, Noncurrent		1,124,500		1,124,500		$ 1,131,800
Utilities Operating Expense, Operations		116,300	$ 85,200	229,200	$ 184,400
Southwestern Electric Power Co [Member] | Revised CCR Rule [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Asset Retirement Obligation		23,800		23,800
Property, Plant and Equipment	[7]	23,800		23,800
Regulatory Assets, Noncurrent		0		0
Utilities Operating Expense, Operations				0
Letters of Credit [Member]
Maximum Future Payments for Letters of Credit [Abstract]
Maximum Future Payments for Letters of Credit Issued Under the Uncommitted Facility		244,500		244,500
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Letters of Credit Limit		1,200,000		1,200,000
Uncommitted Facility		450,000		450,000
Letters of Credit [Member] | AEP Texas Inc. [Member]
Maximum Future Payments for Letters of Credit [Abstract]
Maximum Future Payments for Letters of Credit Issued Under the Uncommitted Facility		1,800		1,800
Letters of Credit [Member] | Appalachian Power Co [Member]
Maximum Future Payments for Letters of Credit [Abstract]
Maximum Future Payments for Letters of Credit Issued Under the Uncommitted Facility		6,300		6,300
March 2029 [Member] | Letters of Credit [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Revolving Credit Facilities		5,000,000		5,000,000
March 2027 [Member] | Letters of Credit [Member]
Commitments, Guarantees and Contingencies (Textuals) [Abstract]
Prior Revolving Credit Facilities		4,000,000		4,000,000
Revolving Credit Facilities		$ 1,000,000		$ 1,000,000

[1] Includes ARO related to wind farms.

[2] Includes ARO related to Sabine and DHLC.

[3] Includes ARO related to ash disposal facilities.

[4] Includes ARO related to asbestos removal.

[5] Includes ARO related to nuclear decommissioning costs for the Cook Plant of $2.1 billion and $2.1 billion as of June 30, 2024 and December 31, 2023, respectively.

[6] Includes ARO related to solar farms.

[7] ARO is related to a legacy CCR surface impoundment or CCR management unit at an operating generation facility.

[8] ARO is related to a legacy CCR surface impoundment or CCR management unit at a retired generation facility and recognition of a regulatory asset in accordance with the accounting guidance for “Regulated Operations” is supported.

[9] ARO is related to a legacy CCR surface impoundment or CCR management unit and recognition of a regulatory asset in accordance with the accounting guidance for “Regulated Operations” is not yet supported.