Revenue Recognition - Management Program (Details) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2018
Vogtle Units No. 3 & No. 4
Operating revenues
Amounts billed under rate management program	$ 4,050	$ 9,440
Cumulative recovery of financing costs	130,482
Vogtle New Units
Operating revenues
Cumulative recovery of financing costs	337,675
Rate management program, additional collection period			5 years
Rate management program, billing period			5 years
Amounts billed under additional rate management program	$ 31,427	$ 5,887