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Current Billing Rates Under Rate ECR, Annual Increase, Amount

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Current billing rates under rate ECR in terms of per units.

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Public Utilities, Deferred Amount, Reliability Reserve

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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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The proportionate share of interest (percent) in a jointly owned utility plant.

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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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Regulatory Matters - APC Plant Greene County (Details) $ in Millions			1 Months Ended
	Oct. 24, 2024 USD ($) MW	May 08, 2024 $ / KWH_Kilowatt_hour	Jan. 31, 2026 $ / KWH_Kilowatt_hour	Jul. 31, 2024 USD ($) $ / KWH_Kilowatt_hour	Sep. 18, 2024 USD ($)	Apr. 26, 2024 MW
ALABAMA POWER CO
Public Utilities, General Disclosures [Line Items]
Current billing rates under rate ECR (usd per KWH) \| $ / KWH_Kilowatt_hour		0.03270		0.03015
Current billing rates under rate ECR, amount \| $				$ 135
Reliability reserve \| $					$ 143
ALABAMA POWER CO \| Tenaska Alabama Partners, L.P. \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Purchase price \| $	$ 622
Approximate nameplate capacity \| MW	855
ALABAMA POWER CO \| Scenario, Forecast
Public Utilities, General Disclosures [Line Items]
Current billing rates under rate ECR (usd per KWH) \| $ / KWH_Kilowatt_hour			0.05910
ALABAMA POWER CO \| Plant Greene County Units 1 and 2
Public Utilities, General Disclosures [Line Items]
Proportionate ownership share						60.00%
Required fossil-stream generation retirements (in MWs) \| MW						300
MISSISSIPPI POWER CO \| Plant Greene County Units 1 and 2
Public Utilities, General Disclosures [Line Items]
Proportionate ownership share						40.00%
Required fossil-stream generation retirements (in MWs) \| MW						206