Regulatory Matters - GPC Nuclear Construction (Details) - GEORGIA POWER CO - Plant Vogtle Units 3 And 4 $ in Millions	12 Months Ended
	Dec. 31, 2012 utility MW	Mar. 31, 2024 USD ($)	Dec. 31, 2009
Loss Contingencies [Line Items]
Proportionate ownership share			45.70%
Number of construction units approved | utility	2
Electric generating capacity in mega watts under consortium agreement | MW	1,100
Estimated cost to complete, construction contingency estimate, financing costs		$ 3,530
Estimated cost to complete, construction contingency estimate, financing costs, incurred to date		3,520
Costs recovered to date		$ 3,070