Regulatory Matters - GPC Plant Vogtle Unit 3 and Common Facilities Rate Proceeding (Details) - GEORGIA POWER CO - USD ($) $ in Millions				1 Months Ended	9 Months Ended	12 Months Ended
	Aug. 30, 2023	Aug. 01, 2023	May 16, 2023	Nov. 30, 2021	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2009	Aug. 31, 2018
Loss Contingencies [Line Items]
Requested rate increase (decrease) amount			$ 1,100
Requested revenues increase (decrease) percentage			54.00%
Plant Vogtle Units 3 And 4
Loss Contingencies [Line Items]
Recovery of construction and capital costs	$ 7,562
Requested recovery of associated retail base items	1,020
Estimated in-service capital cost							$ 4,418
Approved rate increase (decrease)	5,462			$ 2,100
Approved recovery of retail rate items				$ 362
Associated retail rate base items	656
Return on equity reduction, negative impact on earnings					$ 12	$ 300
Requested rate increase (decrease) amount	$ 729
Requested revenues increase (decrease) percentage	5.00%
Percentage of ownership interest required for voting for continuing construction								90.00%
Percentage of costs, disallowed for recovery					6.00%
Plant Vogtle Unit 3
Loss Contingencies [Line Items]
Requested rate increase, annual amount		$ 318
Seventeenth Vogtle Construction Monitoring Report | Plant Vogtle Units 3 And 4
Loss Contingencies [Line Items]
Recovery of construction and capital costs	$ 8,826
Requested recovery of associated retail base items	$ 1,070
Twenty Fourth Vogtle Construction Monitoring Report | Plant Vogtle Units 3 And 4
Loss Contingencies [Line Items]
Cost settlement agreement revised forecast, net of payments					$ 7,300