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Contingencies - General Litigation Matters (Details) - Pending Litigation $ in Millions | 1 Months Ended | 5 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 31, 2019 plaintiff | Feb. 28, 2022 claim | Dec. 31, 2018 USD ($) plaintiff defendant
GEORGIA POWER CO | Class Action Lawsuit |  |  |
Loss Contingencies [Line Items] |  |  |
Complaints filed | claim |  | 8 |
MISSISSIPPI POWER CO | Purported Violations of Mississippi Consumer Protection Act |  |  |
Loss Contingencies [Line Items] |  |  |
Number of plaintiffs |  |  | 10
Number of defendants | defendant |  |  | 3
Number of additional plaintiffs | 4 |  |
Underpayment of refunds | $ |  |  | $ 23.5

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