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CONTINGENCIES, COMMITMENTS, AND GUARANTEES - GAS Commitments (Details) - Southern Company Gas MMBTU in Millions, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 USD ($) MMBTU
Long-term Purchase Commitment [Line Items] |
Natural gas pipeline capacity | MMBTU | 38
Long-term purchase commitment amount | $ 98
Pipeline Charges, Storage Capacity, and Gas Supply |
Pipeline Charges, Storage Capacity, and Gas Supply |
2024 | 587
2025 | 432
2026 | 231
2027 | 148
2028 | 103
Thereafter | 785
Total | $ 2,286

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