FINANCING - Maturities of Long-Term Debt (Details) $ in Millions	Dec. 31, 2024 USD ($)
Debt Instrument [Line Items]
2025	$ 4,727
2026	3,792
2027	4,075
2028	2,827
2029	1,990
Alabama Power
Debt Instrument [Line Items]
2025	658
2026	47
2027	551
2028	107
2029	0
Alabama Power \| Series 2023A Convertible Senior Notes Due 2025
Debt Instrument [Line Items]
2025	200
Georgia Power
Debt Instrument [Line Items]
2025	967
2026	451
2027	1,015
2028	868
2029	861
Georgia Power \| Series 2023C Convertible Senior Notes Due 2074
Debt Instrument [Line Items]
2025	117
Mississippi Power
Debt Instrument [Line Items]
2025	12
2026	66
2027	10
2028	357
2029	1
Southern Power
Debt Instrument [Line Items]
2025	500
2026	964
2027	0
2028	0
2029	0
Southern Power \| Euro-denominated Debt
Debt Instrument [Line Items]
2026	564
Southern Company Gas
Debt Instrument [Line Items]
2025	300
2026	530
2027	154
2028	150
2029	$ 150

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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