FINANCING ACTIVITIES - Dividend Restrictions Narrative (Details)	3 Months Ended
	Mar. 31, 2026
Dividends Payable [Line Items]
Maximum percentage debt to capitalization	67.50%
INDIANA MICHIGAN POWER COMPANY
Dividends Payable [Line Items]
Maximum percentage debt to capitalization	67.50%
AEP TEXAS INC.
Dividends Payable [Line Items]
Maximum percentage debt to capitalization	67.50%
APPALACHIAN POWER COMPANY
Dividends Payable [Line Items]
Maximum percentage debt to capitalization	67.50%
SOUTHWESTERN ELECTRIC POWER COMPANY
Dividends Payable [Line Items]
Maximum percentage debt to capitalization	67.50%
PUBLIC SERVICE COMPANY OF OKLAHOMA
Dividends Payable [Line Items]
Maximum percentage debt to capitalization	67.50%
AEP TRANSMISSION COMPANY, LLC
Dividends Payable [Line Items]
Maximum percentage debt to capitalization	67.50%