Regulatory Matters - GPC Nuclear Construction Cost and Schedule (Details) - GEORGIA POWER CO - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12003 Months Ended
	Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Loss Contingencies [Line Items]
Pre-tax charge to income	$ 160		$ 407
Plant Vogtle Units 3 And 4
Loss Contingencies [Line Items]
Base project capital cost forecast	10,736	$ 10,736
Construction contingency estimate	17	17
Total project capital cost forecast	10,753	10,753
Net investment as of end of the period	(10,495)	(10,495)
Remaining estimate to complete	258	258
Estimated cost to complete, costs not shared with other owners	610	610
Estimated cost to complete, construction monitoring costs approved for recovery	33	33
Pre-tax charge to income			$ 567
Expected capitalized costs		420
Capitalized interest accrued	385	385
Plant Vogtle Units 3 And 4 | Twenty Fifth Vogtle Construction Monitoring Report
Loss Contingencies [Line Items]
Guarantor obligations	$ 1,700	1,700
Customer refund		$ 188