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Contingencies - General Litigation Matters (Details) $ in Millions | 1 Months Ended | 12 Months Ended | 16 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2019 plaintiff | Dec. 31, 2021 USD ($) project | Dec. 31, 2018 USD ($) plaintiff defendant | Jan. 31, 2023 claim | Jun. 30, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2010 USD ($)
MISSISSIPPI POWER CO | Kemper IGCC |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
DOE awards |  |  |  |  |  |  | $ 137.0 | $ 270.0
Government grants received |  |  | $ 387.0 |  |  |  |  |
MISSISSIPPI POWER CO | Pending Litigation | Purported Violations of Mississippi Consumer Protection Act |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Number of plaintiffs | plaintiff |  |  | 10 |  |  |  |  |
Number of defendants | defendant |  |  | 3 |  |  |  |  |
Number of additional plaintiffs | plaintiff | 4 |  |  |  |  |  |  |
Underpayment of refunds |  |  | $ 23.5 |  |  |  |  |
GEORGIA POWER CO | Pending Litigation | Class Action Lawsuit |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Complaints filed | claim |  |  |  | 8 |  |  |  |
SOUTHERN POWER CO | Proceeds From Issuance Of Solid Waste Disposal Facility Revenue Bonds |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Restricted cash |  |  |  |  | $ 17.0 | $ 17.0 |  |
SOUTHERN POWER CO | Settled Litigation | Southern Power vs First Solar |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Number of solar projects | project |  | 5 |  |  |  |  |  |
Proceeds from legal settlements |  | $ 36.0 |  |  |  |  |  |

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