Approximate Nameplate Capacity

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- Definition

Minimum Natural Disaster Reserve Balance, Triggering Establishment Charge

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- Definition

Natural Disaster Reserve Authorized Limit

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- Definition

Natural Disaster Reserve, Expected Recovery Amount

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- Definition

Public Utilities, Deferred Amount, Reliability Reserve

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- 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.

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Amortization period for the recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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Regulatory Matters - Alabama Power (Details) $ in Millions		6 Months Ended	12 Months Ended
Regulatory Matters - Alabama Power (Details) $ in Millions	Jun. 06, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 05, 2025 USD ($) MW	Dec. 31, 2024 USD ($)
Loss Contingencies [Line Items]
Regulatory asset balance related to storm damage				$ 867		$ 705
ALABAMA POWER CO
Loss Contingencies [Line Items]
Regulatory asset balance related to storm damage				2
Minimum natural disaster reserve balance, triggering establishment charge				50
Natural disaster reserve authorized limit				75
Reliability reserve				$ 131
ALABAMA POWER CO \| Jurisdictional Separation Study Order (JSS)
Loss Contingencies [Line Items]
Regulatory asset balance related to storm damage					$ 100
Regulatory asset amortization period					10 years
ALABAMA POWER CO \| Tenaska Alabama Partners, L.P.
Loss Contingencies [Line Items]
Approximate nameplate capacity \| MW					855
Purchase price	$ 622
ALABAMA POWER CO \| Scenario, Forecast
Loss Contingencies [Line Items]
Natural disaster reserve, expected recovery amount		$ 18	$ 36