FINANCING ACTIVITIES - Schedule of Direct Borrowing Activity (Details) - Direct Borrowing $ in Millions	9 Months Ended
Sep. 30, 2026 USD ($)
AEPTCo
Short-Term Debt [Line Items]
Maximum Borrowings	$ 133
Maximum Loans	578
Average Borrowings	131
Average Loans	194
Borrowings	0
Loans	112
Authorized Short-term Borrowing Limit	0
Midwest Transmission Holdings
Short-Term Debt [Line Items]
Maximum Borrowings	0
Maximum Loans	10
Average Borrowings	0
Average Loans	0
Borrowings	0
Loans	10
Authorized Short-term Borrowing Limit	0
SWTCo
Short-Term Debt [Line Items]
Maximum Borrowings	2
Maximum Loans	0
Average Borrowings	2
Average Loans	0
Borrowings	2
Loans	0
Authorized Short-term Borrowing Limit	$ 50

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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- 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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- Definition

Borrowings from Parent at period end. Parent 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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- Definition

Loans to Parent at period end. Parent 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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- 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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Period Type:	duration

- 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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Namespace Prefix:	aep_
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Balance Type:	debit
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480657/210-10-S50-8

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- Details

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