REGULATORY MATTERS - GPC Nuclear Construction (Details) $ in Millions	3 Months Ended				12 Months Ended
	Dec. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2012 utility MW
Public Utilities, General Disclosures [Line Items]
Estimated loss on Plant Vogtle Units 3 and 4					$ 183	$ 1,692	$ 325
Georgia Power
Public Utilities, General Disclosures [Line Items]
Number of construction units approved | utility								2
Electric generating capacity (in MWs) | MW								1,100
Estimated cost to complete, pre-tax charge to income	$ 148	$ 32	$ 36
Estimated cost to complete, pre-tax charge to income, net of tax	110	24	27
Estimated loss on Plant Vogtle Units 3 and 4					183	$ 1,692	$ 325
Pre-tax charge to income	53	(102)	16	$ 440	$ 407
After tax charge to income	$ 40	$ (76)	$ 12	$ 328
Plant Vogtle Units 3 and 4 | Georgia Power
Public Utilities, General Disclosures [Line Items]
Percent ownership	45.70%				45.70%
Estimated construction financing costs	$ 3,500				$ 3,500
Construction financing costs incurred to date	3,200				3,200
Estimated cost to complete, construction contingency estimate and additional costs	307				307
Estimated cost to complete, additional construction contingency estimate	125				125
Estimated cost to complete, additional construction monitoring costs	9				$ 9
Plant Vogtle Units 3 and 4 | Georgia Power | Minimum | COVID-19
Public Utilities, General Disclosures [Line Items]
Estimated months of productivity loss					3 months
Construction financing costs	160				$ 160
Plant Vogtle Units 3 and 4 | Georgia Power | Maximum | COVID-19
Public Utilities, General Disclosures [Line Items]
Estimated months of productivity loss					4 months
Construction financing costs	$ 200				$ 200
Plant Vogtle Units 3 and 4 | Georgia Power | Vogtle Owners
Public Utilities, General Disclosures [Line Items]
Period of notice required in the event letters of credit are not renewed					30 days
Plant Vogtle Unit 3 | Georgia Power
Public Utilities, General Disclosures [Line Items]
Additional base capital costs per month (up to)					$ 15
Plant Watson Unit 4 | Georgia Power
Public Utilities, General Disclosures [Line Items]
Additional base capital costs per month (up to)					$ 35