Contingencies - Environmental Remediation (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
GEORGIA POWER CO
Loss Contingencies [Line Items]
Environmental remediation liability, current and former sites	$ 13	$ 13
SOUTHERN Co GAS
Loss Contingencies [Line Items]
Environmental remediation liability, current and former sites	$ 227	$ 222

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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+ Details