FINANCING ACTIVITIES - Schedule of Utility Money Pool Participants' Money Pool Activity and Authorized Borrowing Limits (Details) - Utility $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($)
AEP TEXAS INC.
Short-Term Debt [Line Items]
Maximum Borrowings	$ 624
Maximum Loans	186
Average Borrowings	403
Average Loans	129
Authorized Short-term Borrowing Limit	750
AEP TEXAS INC. \| Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	105
AEP TRANSMISSION COMPANY, LLC
Short-Term Debt [Line Items]
Maximum Borrowings	205
Maximum Loans	342
Average Borrowings	60
Average Loans	85
Authorized Short-term Borrowing Limit	820
AEP TRANSMISSION COMPANY, LLC \| Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	211
APPALACHIAN POWER COMPANY
Short-Term Debt [Line Items]
Maximum Borrowings	307
Maximum Loans	17
Average Borrowings	173
Average Loans	17
Authorized Short-term Borrowing Limit	750
APPALACHIAN POWER COMPANY \| Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	(160)
INDIANA MICHIGAN POWER COMPANY
Short-Term Debt [Line Items]
Maximum Borrowings	146
Maximum Loans	855
Average Borrowings	46
Average Loans	241
Authorized Short-term Borrowing Limit	750
INDIANA MICHIGAN POWER COMPANY \| Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	(9)
OHIO POWER COMPANY
Short-Term Debt [Line Items]
Maximum Borrowings	155
Maximum Loans	42
Average Borrowings	74
Average Loans	17
Authorized Short-term Borrowing Limit	600
OHIO POWER COMPANY \| Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	(139)
PUBLIC SERVICE COMPANY OF OKLAHOMA
Short-Term Debt [Line Items]
Maximum Borrowings	487
Maximum Loans	0
Average Borrowings	279
Average Loans	0
Authorized Short-term Borrowing Limit	750
PUBLIC SERVICE COMPANY OF OKLAHOMA \| Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	(487)
SOUTHWESTERN ELECTRIC POWER COMPANY
Short-Term Debt [Line Items]
Maximum Borrowings	293
Maximum Loans	1,308
Average Borrowings	120
Average Loans	85
Authorized Short-term Borrowing Limit	750
SOUTHWESTERN ELECTRIC POWER COMPANY \| Related Party
Short-Term Debt [Line Items]
Net Loans to (Borrowings from)	$ (293)

Authorized Short-term Borrowing Limit by regulatory orders.

No definition available.

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- Definition

Average Borrowings from a Money Pool during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Average Loans to a Money Pool during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum Borrowings from a Money Pool at anytime during the period. The Money Pool represents a centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.

+ References

No definition available.

+ Details

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- Definition

Maximum Loans to a Money Pool at anytime during the period. The Money Pool represents centralized funding mechanism AEP uses to meet the short-term cash requirements of certain subsidiaries.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Net Loans to (Borrowings from) the Utility Money

+ References

No definition available.

+ Details

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Namespace Prefix:	aep_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

Name:	dei_LegalEntityAxis=aep_AppalachianPowerCompanyMember
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- Details

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- Details

Name:	dei_LegalEntityAxis=aep_OhioPowerCompanyMember
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- Details

Name:	dei_LegalEntityAxis=aep_PublicServiceCompanyOfOklahomaMember
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