XML 211 R140.htm IDEA: XBRL DOCUMENT
v3.25.0.1

EFFECTS OF REGULATION - Regulatory Liabilities - SWEPCO (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Regulatory Liability [Line Items] |  |
Total Current Regulatory Liabilities | $ 53.5 | $ 26.5
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 8,344.0 | 8,182.4
Pending final regulatory determination |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 322.0 | 207.9
Approved for payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 8,022.0 | 7,974.5
Pays/paying a return | Over-recovered Fuel Costs |  |
Regulatory Liability [Line Items] |  |
Total Current Regulatory Liabilities | $ 21.6 | 3.3
Remaining Refund Period | 1 year |
Pays/paying a return | Pending final regulatory determination |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | $ 176.0 | 103.1
Pays/paying a return | Pending final regulatory determination | Income Taxes, Net |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 176.0 | 103.1
Pays/paying a return | Approved for payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 5,526.4 | 5,823.1
Pays/paying a return | Approved for payment | Income Taxes, Net |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 1,622.1 | 2,179.7
Pays/paying a return | Approved for payment | Asset Removal Costs |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 3,828.0 | 3,563.5
Pays/paying a return | Approved for payment | Other Regulatory Liabilities Approved for Payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 40.4 | 35.0
Does not pay/paying a return | Over-recovered Fuel Costs |  |
Regulatory Liability [Line Items] |  |
Total Current Regulatory Liabilities | $ 31.9 | 23.2
Remaining Refund Period | 1 year |
Does not pay/paying a return | Pending final regulatory determination |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | $ 146.0 | 104.8
Does not pay/paying a return | Approved for payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | $ 2,495.6 | 2,151.4
Does not pay/paying a return | Approved for payment | Over-recovered Fuel Costs |  |
Regulatory Liability [Line Items] |  |
Remaining Refund Period | 8 years |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | $ 32.1 | 26.1
Does not pay/paying a return | Approved for payment | Other Regulatory Liabilities Approved for Payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 90.1 | 106.5
SOUTHWESTERN ELECTRIC POWER COMPANY |  |
Regulatory Liability [Line Items] |  |
Total Current Regulatory Liabilities | 21.6 | 3.3
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 610.8 | 756.1
SOUTHWESTERN ELECTRIC POWER COMPANY | Pending final regulatory determination |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 7.0 | 7.0
SOUTHWESTERN ELECTRIC POWER COMPANY | Approved for payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 603.8 | 749.1
SOUTHWESTERN ELECTRIC POWER COMPANY | Pays/paying a return | Over-recovered Fuel Costs |  |
Regulatory Liability [Line Items] |  |
Total Current Regulatory Liabilities | $ 21.6 | 3.3
Remaining Refund Period | 1 year |
SOUTHWESTERN ELECTRIC POWER COMPANY | Pays/paying a return | Pending final regulatory determination | Income Taxes, Net |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | $ 7.0 | 7.0
SOUTHWESTERN ELECTRIC POWER COMPANY | Pays/paying a return | Approved for payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 591.4 | 740.0
SOUTHWESTERN ELECTRIC POWER COMPANY | Pays/paying a return | Approved for payment | Income Taxes, Net |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 127.5 | 292.4
SOUTHWESTERN ELECTRIC POWER COMPANY | Pays/paying a return | Approved for payment | Asset Removal Costs |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 456.6 | 443.2
SOUTHWESTERN ELECTRIC POWER COMPANY | Pays/paying a return | Approved for payment | Other Regulatory Liabilities Approved for Payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 7.3 | 4.4
SOUTHWESTERN ELECTRIC POWER COMPANY | Does not pay/paying a return | Approved for payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | 12.4 | 9.1
SOUTHWESTERN ELECTRIC POWER COMPANY | Does not pay/paying a return | Approved for payment | Other Regulatory Liabilities Approved for Payment |  |
Regulatory Liability [Line Items] |  |
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits | $ 12.4 | $ 9.1

X
- 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
Name: | us-gaap_RegulatoryLiabilitiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amortization period for the recovery of regulatory liability, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_RegulatoryLiabilityAmortizationPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 405 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477571/980-405-25-1 + Details
Name: | us-gaap_RegulatoryLiabilityCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_RegulatoryLiabilityNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | aep_RegulatoryAssetsOrLiabilityRegulatoryStatusAxis=aep_RegulatoryLiabilityPendingFinalDeterminationIncludingNettingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_RegulatoryAssetsOrLiabilityRegulatoryStatusAxis=aep_RegulatoryLiabilityApprovedForPaymentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_RegulatoryAssetsOrLiabilityReturnStatusAxis=aep_RegulatoryLiabilityPaysAReturnMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=us-gaap_DeferredFuelCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=aep_IncomeTaxesNetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=aep_AssetRemovalCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=aep_OtherRegulatoryLiabilitiesApprovedForPaymentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_RegulatoryAssetsOrLiabilityReturnStatusAxis=aep_RegulatoryLiabilityNotPayAReturnMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=aep_SouthwesternElectricPowerCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |