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Derivatives - Schedule of Interest Rate Derivatives (Details) - Interest rate derivatives $ in Millions | 9 Months Ended
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Sep. 30, 2024 USD ($)
Derivative [Line Items] |
Notional Amount | $ 2,250
Fair Value Gain (Loss) | (217)
GEORGIA POWER CO | Cash Flow Hedges of Forecasted Debt | Date One |
Derivative [Line Items] |
Notional Amount | $ 350
Weighted Average Interest Rate Paid | 3.53%
Fair Value Gain (Loss) | $ 1
Southern Company parent | 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) | $ (32)
Southern Company parent | Fair Value Hedges of Existing Debt | Date Two |
Derivative [Line Items] |
Notional Amount | $ 1,000
Weighted Average Interest Rate Paid | 2.48%
Interest Rate Received | 3.70%
Fair Value Gain (Loss) | $ (124)
SOUTHERN Co GAS | Fair Value Hedges of Existing Debt |
Derivative [Line Items] |
Fair Value Gain (Loss) | (62)
SOUTHERN Co GAS | Fair Value Hedges of Existing Debt | Date Three |
Derivative [Line Items] |
Notional Amount | $ 500
Weighted Average Interest Rate Paid | 0.49%
Interest Rate Received | 1.75%

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