PROPERTY, PLANT, AND EQUIPMENT - Property, Plant and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Electric utilities:
Generation	$ 61,292	$ 57,325
Transmission	16,280	15,561
Distribution	28,678	26,482
General/other	6,547	6,305
Electric utilities' plant in service	112,797	105,673
Southern Company Gas:
Natural gas transportation and distribution	18,896	17,798
Storage facilities	1,748	1,565
Other	1,694	1,477
Southern Company Gas plant in service	22,338	20,840
Other plant in service	2,008	1,915
Total plant in service	137,143	128,428
Alabama Power
Electric utilities:
Generation	16,801	16,584
Transmission	6,449	6,152
Distribution	10,373	9,775
General/other	2,878	2,918
Electric utilities' plant in service	36,501	35,429
Southern Company Gas:
Natural gas transportation and distribution	0	0
Storage facilities	0	0
Other	0	0
Southern Company Gas plant in service	0	0
Other plant in service	0	0
Total plant in service	36,501	35,429
Georgia Power
Electric utilities:
Generation	26,089	22,587
Transmission	8,800	8,402
Distribution	16,887	15,380
General/other	3,260	3,001
Electric utilities' plant in service	55,036	49,370
Southern Company Gas:
Natural gas transportation and distribution	0	0
Storage facilities	0	0
Other	0	0
Southern Company Gas plant in service	0	0
Other plant in service	0	0
Total plant in service	55,036	49,370
Mississippi Power
Electric utilities:
Generation	2,946	2,909
Transmission	989	966
Distribution	1,418	1,327
General/other	344	321
Electric utilities' plant in service	5,697	5,523
Southern Company Gas:
Natural gas transportation and distribution	0	0
Storage facilities	0	0
Other	0	0
Southern Company Gas plant in service	0	0
Other plant in service	0	0
Total plant in service	5,697	5,523
Southern Power
Electric utilities:
Generation	14,920	14,649
Transmission	0	0
Distribution	0	0
General/other	41	41
Electric utilities' plant in service	14,961	14,690
Southern Company Gas:
Natural gas transportation and distribution	0	0
Storage facilities	0	0
Other	0	0
Southern Company Gas plant in service	0	0
Other plant in service	0	0
Total plant in service	14,961	14,690
Southern Company Gas
Electric utilities:
Generation	0	0
Transmission	0	0
Distribution	0	0
General/other	0	0
Electric utilities' plant in service	0	0
Southern Company Gas:
Natural gas transportation and distribution	18,896	17,798
Storage facilities	1,748	1,565
Other	1,694	1,477
Southern Company Gas plant in service	22,338	20,840
Other plant in service	0	0
Total plant in service	$ 22,338	$ 20,840

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Other Equipment.

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Utility Plant in Service.

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Period end amount of property, plant and equipment (PPE) related to generation or processing owned by public utility.

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Period end amount of total gross PPE.

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Period end amount of property, plant and equipment (PPE) related to utility transmission owned by public utility.

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