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DERIVATIVES - Interest Rate Derivatives (Details) - Interest rate derivatives $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($)
Derivative [Line Items] |
Notional Amount | $ 2,200
Fair Value Gain (Loss) December 31, 2023 | (264)
Southern Company | Fair Value Hedges of Existing Debt | Date one |
Derivative [Line Items] |
Notional Amount | $ 400
Weighted Average Interest Rate Paid | 0.80%
Interest Rate Received | 1.75%
Fair Value Gain (Loss) December 31, 2023 | $ (46)
Southern Company | Fair Value Hedges of Existing Debt | Date 2 |
Derivative [Line Items] |
Notional Amount | $ 1,000
Weighted Average Interest Rate Paid | 2.48%
Interest Rate Received | 3.70%
Fair Value Gain (Loss) December 31, 2023 | $ (139)
Southern Company Gas | Fair Value Hedges of Existing Debt |
Derivative [Line Items] |
Notional Amount | $ 500
Weighted Average Interest Rate Paid | 0.49%
Interest Rate Received | 1.75%
Fair Value Gain (Loss) December 31, 2023 | $ (79)
Georgia Power | Cash Flow Hedges of Forecasted Debt |
Derivative [Line Items] |
Notional Amount | $ 150
Weighted Average Interest Rate Paid | 4.01%
Fair Value Gain (Loss) December 31, 2023 | $ 0
Mississippi Power | Cash Flow Hedges of Forecasted Debt | Date one |
Derivative [Line Items] |
Notional Amount | $ 75
Weighted Average Interest Rate Paid | 3.84%
Fair Value Gain (Loss) December 31, 2023 | $ 0
Mississippi Power | Cash Flow Hedges of Forecasted Debt | Date 2 |
Derivative [Line Items] |
Notional Amount | $ 75
Weighted Average Interest Rate Paid | 4.04%
Fair Value Gain (Loss) December 31, 2023 | $ 0

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