CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Common Stock	Paid-in Capital	Retained Earnings		Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2023		527,400,000
Beginning balance at Dec. 31, 2023	$ 25,285.9	$ 3,427.9	$ 9,073.9	$ 12,800.4		$ (55.5)	$ 39.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock (in shares)		800,000
Issuance of Common Stock	40.6	$ 5.4	35.2
Common Stock Dividends	(466.9)			(465.5)	[1]		(1.4)
Other Changes in Equity	(14.8)		(14.8)
Net Income (Loss)	1,005.7			1,003.1			2.6
Other Comprehensive Income (Loss)	(6.8)					(6.8)
Ending balance (in shares) at Mar. 31, 2024		528,200,000
Ending balance at Mar. 31, 2024	25,843.7	$ 3,433.3	9,094.3	13,338.0		(62.3)	40.4
Beginning balance (in shares) at Dec. 31, 2023		527,400,000
Beginning balance at Dec. 31, 2023	25,285.9	$ 3,427.9	9,073.9	12,800.4		(55.5)	39.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	2,309.9
Other Comprehensive Income (Loss)	(31.4)					(31.4)
Ending balance (in shares) at Sep. 30, 2024		533,700,000
Ending balance at Sep. 30, 2024	26,658.8	$ 3,468.7	9,534.9	13,700.7		(86.9)	41.4
Beginning balance (in shares) at Mar. 31, 2024		528,200,000
Beginning balance at Mar. 31, 2024	25,843.7	$ 3,433.3	9,094.3	13,338.0		(62.3)	40.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock (in shares)		4,900,000
Issuance of Common Stock	435.2	$ 32.1	403.1
Common Stock Dividends	(469.1)			(467.0)	[1]		(2.1)
Other Changes in Equity	1.1		1.1
Net Income (Loss)	342.5			340.3			2.2
Other Comprehensive Income (Loss)	22.3					22.3
Ending balance (in shares) at Jun. 30, 2024		533,100,000
Ending balance at Jun. 30, 2024	26,175.7	$ 3,465.4	9,498.5	13,211.3		(40.0)	40.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock (in shares)		600,000
Issuance of Common Stock	37.2	$ 3.3	33.9
Common Stock Dividends	(471.4)			(470.2)	[1]		(1.2)
Other Changes in Equity	2.5		2.5
Net Income (Loss)	961.7			959.6			2.1
Other Comprehensive Income (Loss)	(46.9)					(46.9)
Ending balance (in shares) at Sep. 30, 2024		533,700,000
Ending balance at Sep. 30, 2024	$ 26,658.8	$ 3,468.7	9,534.9	13,700.7		(86.9)	41.4
Beginning balance (in shares) at Dec. 31, 2024	534,094,530	534,100,000
Beginning balance at Dec. 31, 2024	$ 26,986.1	$ 3,471.6	9,606.1	13,869.2		(3.1)	42.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock (in shares)		1,100,000
Issuance of Common Stock	75.4	$ 7.1	68.3
Common Stock Dividends	(501.0)			(500.0)	[2]		(1.0)
Other Changes in Equity	(22.1)		(22.1)
Net Income (Loss)	802.2			800.2			2.0
Other Comprehensive Income (Loss)	23.4					23.4
Ending balance (in shares) at Mar. 31, 2025		535,200,000
Ending balance at Mar. 31, 2025	$ 27,364.0	$ 3,478.7	9,652.3	14,169.4		20.3	43.3
Beginning balance (in shares) at Dec. 31, 2024	534,094,530	534,100,000
Beginning balance at Dec. 31, 2024	$ 26,986.1	$ 3,471.6	9,606.1	13,869.2		(3.1)	42.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	3,090.8
Other Comprehensive Income (Loss)	$ (24.7)					(24.7)
Ending balance (in shares) at Sep. 30, 2025	536,312,729	536,300,000
Ending balance at Sep. 30, 2025	$ 31,479.3	$ 3,486.0	11,561.8	15,369.3		(27.8)	1,090.0
Beginning balance (in shares) at Mar. 31, 2025		535,200,000
Beginning balance at Mar. 31, 2025	27,364.0	$ 3,478.7	9,652.3	14,169.4		20.3	43.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock (in shares)		600,000
Issuance of Common Stock	56.4	$ 3.7	52.7
Common Stock Dividends	(499.5)			(498.5)	[2]		(1.0)
Other Changes in Equity	9.2		9.1				0.1
Midwest Transmission Holdings Noncontrolling Interest Transaction	2,782.9		1,790.5				992.4
Net Income (Loss)	1,288.3			1,225.8			62.5
Other Comprehensive Income (Loss)	(32.9)					(32.9)
Ending balance (in shares) at Jun. 30, 2025		535,800,000
Ending balance at Jun. 30, 2025	30,968.4	$ 3,482.4	11,504.6	14,896.7		(12.6)	1,097.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Common Stock (in shares)		500,000
Issuance of Common Stock	55.7	$ 3.6	52.1
Capital Contribution from Noncontrolling Interest	33.9						33.9
Common Stock Dividends	(499.4)			(499.4)	[2]
Other Changes in Equity	5.1		5.1
Dividends Paid to Noncontrolling Interest	(69.5)						(69.5)
Net Income (Loss)	1,000.3			972.0			28.3
Other Comprehensive Income (Loss)	$ (15.2)					(15.2)
Ending balance (in shares) at Sep. 30, 2025	536,312,729	536,300,000
Ending balance at Sep. 30, 2025	$ 31,479.3	$ 3,486.0	$ 11,561.8	$ 15,369.3		$ (27.8)	$ 1,090.0

[1] Cash dividends declared per AEP common share were $0.88.

[2] Cash dividends declared per AEP common share were $0.93.