Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Stock Based Compensation (Textuals)
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		10,000,000
Number of Shares Remaining Available for Issuance Under the AEP Long-Term Incentive Plan		3,698,144
Reduction in Aggregate Common Shares Authorized Per Share Issued Pursuant to Stock Options or Stock Appreciation Rights		0.286
Performance Units and AEP Career Shares Reinvested Dividends Portion For [Member]
Performance Units
Awarded Units	[1]	81,300	63,300	74,500
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology
Weighted Average Grant Date Fair Value		$ 82.02	$ 98.73	$ 84.48
Stock Based Compensation [Member]
Compensation Cost and Actual Tax Benefit Realized for the Tax Deductions from Compensation Cost for Share-based Payment Arrangements
Compensation Cost for Share-based Payment Arrangements	[2]	$ 50.9	$ 63.3	$ 61.1
Actual Tax Benefit Realized		6.4	8.0	8.7
Total Compensation Cost Capitalized		15.3	$ 16.0	$ 16.9
Stock Based Compensation (Textuals)
Total Unrecognized Compensation Cost Related to Unvested Share-based Compensation Arrangements Granted		$ 66.0
Weighted-average Period of Unrecognized Compensation Costs (in years)		1 year 4 months 24 days
Stock Unit Accumulation Plan for Non Employee Directors [Member]
Stock Based Compensation (Textuals)
Number of Years After Termination of Board Service Participant Can Elect to Have Stock Units Paid in Cash		10 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology
Weighted Average Grant Date Fair Value		$ 82.14	$ 95.16	$ 84.54
Awarded Units		19,800	14,500	12,600
Restricted Stock Units (RSUs) [Member]
Total Fair Value and Total Intrinsic Value of Restricted Shares and Restricted Stock Units Vested
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value		$ 18.8	$ 17.8	$ 20.5
Intrinsic Value of Restricted Shares and Restricted Stock Units Vested	[3]	$ 19.0	$ 20.3	$ 22.0
Status of Nonvested Restricted Shares and Restricted Stock Units
Nonvested, Shares/Units, Beginning Balance		459,600
Nonvested, Weighted Average Grant Date Fair Value, Beginning of Period		$ 88.05
Shares/Units, Vested		(212,400)
Weighted Average Grant Date Fair Value, Vested		$ 88.47
Shares/Units, Forfeited		(84,500)
Weighted Average Grant Date Fair Value, Shares/Units, Forfeited		$ 86.84
Nonvested, Shares/Units, Ending Balance		431,100	459,600
Nonvested, Weighted Average Grant Date Fair Value, End of Period		$ 88.57	$ 88.05
Stock Based Compensation (Textuals)
Maximum Contractual Term of Outstanding Restricted Stock Units (in months)		40 months
Total Aggregate Intrinsic Value of Nonvested Shares		$ 33.0
Weighted Average Remaining Contractual Life of Nonvested Shares (in years)		1 year 6 months
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology
Weighted Average Grant Date Fair Value		$ 88.52	$ 90.48	$ 80.39
Awarded Units		268,400	290,400	280,000.0
Performance Units [Member]
Performance Units
Awarded Units		486,700	530,300	565,000.0
Vesting Period (in years)		3 years	3 years	3 years
Certified Performance Scores and Units Earned
Certified Performance Score		106.10%	131.10%	102.90%
Performance Units Earned		540,863	512,660	537,166
Performance Units Manditorily Deferred as AEP Career Shares		70,377	28,282	14,613
Performance Units Voluntarily Deferred into the Incentive Compensation Deferral Program		22,716	23,609	22,915
Share Based Compensation Performance Units to be Settled in Shares	[4]	447,770	460,769	499,638
Cash Payouts
Equity Payouts for Performance Units		$ 41.8	$ 43.2	$ 54.7
Stock Based Compensation (Textuals)
Performance Score by HR Committee, Lower Range		0.00%
Performance Score by HR Committee, Higher Range		200.00%
Equity Payouts For Career Share Distributions		$ 8.3	$ 5.1	$ 4.0
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	[5]	2 years 10 months 13 days	2 years 10 months 9 days	2 years 10 months 17 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum		21.23%	25.92%	25.87%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum		39.00%	40.82%	39.90%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate		4.32%	1.64%	0.19%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	[6]	0.00%	0.00%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate		25.35%	31.09%	31.01%
Weighted Average Grant Date Fair Value		$ 98.63	$ 97.61	$ 81.02
Performance Units and Reinvested Dividends [Member]
Share Based Compensation Performance Units Converted to Shares	[7]	448,000
Performance Units
Awarded Units		59,800
Status of Nonvested Restricted Shares and Restricted Stock Units
Nonvested, Shares/Units, Beginning Balance		1,012,200
Nonvested, Weighted Average Grant Date Fair Value, Beginning of Period		$ 90.27
Shares/Units, Vested	[7]	(514,600)
Weighted Average Grant Date Fair Value, Vested		$ 82.33
Shares/Units, Forfeited		(154,200)
Weighted Average Grant Date Fair Value, Shares/Units, Forfeited		$ 86.73
Nonvested, Shares/Units, Ending Balance		889,900	1,012,200
Nonvested, Weighted Average Grant Date Fair Value, End of Period		$ 99.49	$ 90.27
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology
Weighted Average Grant Date Fair Value		$ 82.02

[1] The vesting period for the reinvested dividends on performance shares is equal to the remaining life of the related performance shares.  Dividends on AEP career shares vest immediately when the dividend is awarded but are not settled in AEP common stock until after the participant’s AEP employment ends.

[2] Compensation cost for share-based payment arrangements is included in Other Operation and Maintenance expenses on the statements of income.

[3] Intrinsic value is calculated as market price at the vesting date.

[4] Performance shares settled in AEP common stock in the quarter following the end of the year shown.

[5] Period from award date to vesting date.

[6] Equivalent to reinvesting dividends.

[7] The vested Performance Shares will be converted to 448 thousand shares based on the closing share price on the day before settlement.