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Contingencies - Environmental Remediation (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
GEORGIA POWER CO
Loss Contingencies [Line Items]
Environmental remediation liability, current and former sites	$ 14	$ 14
SOUTHERN Co GAS
Loss Contingencies [Line Items]
Environmental remediation liability, current and former sites	$ 219	$ 227

X

- Definition

Carrying amount of the liability for remediation of environmental damage pertaining to assets or businesses previously disposed.

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