Significant Accounting Matters (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Amounts Attributable to AEP Common Shareholders
Earnings Attributable to Common Shareholders		$ 1,003,100	$ 397,000
Weighted Average Number of Basic AEP Common Shares Outstanding		526,552,036	514,176,648
Total Basic Earnings Per Share Attributable to AEP Common Shareholders		$ 1.91	$ 0.77
Weighted Average Dilutive Effect of:
Weighted Average Number of Diluted AEP Common Shares Outstanding		527,596,395	515,598,090
Total Diluted Earnings Per Share Attributable to AEP Common Shareholders		$ 1.90	$ 0.77
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		$ 230,700		$ 330,100
Restricted Cash		51,100		48,900
Total Cash, Cash Equivalents and Restricted Cash		281,800	$ 393,500	379,000	$ 556,500
Proceeds from Issuance of Debt	[1]	868,000
Securities Received as Collateral		86,000		46,000
Cash Paid for Interest, Net of Capitalized Amounts		368,300	311,900
Net Cash Paid (Received) for Income Taxes		16,100	15,800
AEP Texas Inc. [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		100		100
Restricted Cash		42,700		34,000
Total Cash, Cash Equivalents and Restricted Cash		42,800	42,600	34,100	32,800
Cash Paid for Interest, Net of Capitalized Amounts		26,900	31,600
AEP Transmission Co [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		0	0	0	0
Cash Paid for Interest, Net of Capitalized Amounts		33,300	16,200
Appalachian Power Co [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		7,600		5,000
Restricted Cash		8,400		14,900
Total Cash, Cash Equivalents and Restricted Cash		16,000	14,600	19,900	21,900
Cash Paid for Interest, Net of Capitalized Amounts		41,500	37,900
Indiana Michigan Power Co [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		5,500	8,500	2,100	4,200
Cash Paid for Interest, Net of Capitalized Amounts		38,700	44,400
Net Cash Paid (Received) for Income Taxes		0	2,400
Ohio Power Co [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		12,500		6,400
Total Cash, Cash Equivalents and Restricted Cash		12,500	9,100	6,400	9,600
Cash Paid for Interest, Net of Capitalized Amounts		19,100	20,900
Public Service Co Of Oklahoma [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		3,500	3,800	2,500	4,000
Cash Paid for Interest, Net of Capitalized Amounts		30,300	22,300
Southwestern Electric Power Co [Member]
Amounts Attributable to AEP Common Shareholders
Earnings Attributable to Common Shareholders		208,100	40,600
Cash, Cash Equivalents and Restricted Cash
Cash and Cash Equivalents		3,800	8,200	$ 2,400	$ 88,400
Cash Paid for Interest, Net of Capitalized Amounts		$ 41,200	$ 45,300
Restricted Stock Units and Performance Share Units [Member]
Weighted Average Dilutive Effect of:
Weighted Average Dilutive Effect of Shares		1,000,000.0	1,400,000
Dilutive Securities, Effect on Basic Earnings Per Share		$ (0.01)	$ 0

[1] Amounts indicated on the statements of cash flows are net of issuance costs and premium or discount and will not tie to the issuance amounts.