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DERIVATIVES - Energy-Related Derivative Contracts (Details) - Energy-related, Natural Gas MMBTU in Millions | Dec. 31, 2024 MMBTU
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Derivative [Line Items] |
Net Purchased mmBtu | 431.0
Alabama Power |
Derivative [Line Items] |
Net Purchased mmBtu | 123.0
Georgia Power |
Derivative [Line Items] |
Net Purchased mmBtu | 116.0
Mississippi Power |
Derivative [Line Items] |
Net Purchased mmBtu | 103.0
Southern Power |
Derivative [Line Items] |
Net Purchased mmBtu | 6.0
Southern Company Gas |
Derivative [Line Items] |
Net Purchased mmBtu | 83.0
Long | Not Designated as Hedging Instrument | Southern Company Gas |
Derivative [Line Items] |
Derivative nonmonetary notional amount net long short position volume | 90.0
Short | Not Designated as Hedging Instrument | Southern Company Gas |
Derivative [Line Items] |
Derivative nonmonetary notional amount net long short position volume | 7.0

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