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Derivatives - Schedule of Energy-Related Derivatives (Details) - Energy-related, Natural Gas MMBTU in Millions | Sep. 30, 2024 MMBTU
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Energy-related derivative contracts |
Net Purchased mmBtu | 479.0
ALABAMA POWER CO |
Energy-related derivative contracts |
Net Purchased mmBtu | 130.0
GEORGIA POWER CO |
Energy-related derivative contracts |
Net Purchased mmBtu | 127.0
MISSISSIPPI POWER CO |
Energy-related derivative contracts |
Net Purchased mmBtu | 109.0
SOUTHERN POWER CO |
Energy-related derivative contracts |
Net Purchased mmBtu | 6.0
SOUTHERN Co GAS |
Energy-related derivative contracts |
Net Purchased mmBtu | 107.0
SOUTHERN Co GAS | Energy-related derivatives not designated as hedging instruments | Long |
Energy-related derivative contracts |
Derivative nonmonetary notional amount net long short position volume | 118.0
SOUTHERN Co GAS | Energy-related derivatives not designated as hedging instruments | Short |
Energy-related derivative contracts |
Derivative nonmonetary notional amount net long short position volume | 11.0

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