Condensed Consolidated Statements of Income (Unaudited) - GAS - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Operating Revenues:
Total operating revenues	$ 6,980	$ 8,378	$ 19,208	$ 22,232
Operating Expenses:
Other operations and maintenance	1,424	1,527	4,352	4,568
Depreciation and amortization	1,143	922	3,365	2,728
Taxes other than income taxes	341	352	1,076	1,073
Total operating expenses	4,870	6,185	14,589	17,000
Operating Income	2,110	2,193	4,619	5,232
Other Income and (Expense):
Earnings from equity method investments	32	28	110	109
Interest expense, net of amounts capitalized	(620)	(511)	(1,812)	(1,461)
Other income (expense), net	141	132	428	414
Total other income and (expense)	(381)	(292)	(1,074)	(775)
Earnings Before Income Taxes	1,729	1,901	3,545	4,457
Income taxes	297	414	492	891
Net Income	1,432	1,487	3,053	3,566
Retail electric revenues
Operating Revenues:
Total operating revenues	5,139	5,961	12,597	14,363
Wholesale electric revenues
Operating Revenues:
Total operating revenues	727	1,197	1,930	2,798
Other electric revenues
Operating Revenues:
Total operating revenues	203	185	602	554
Natural Gas
Operating Revenues:
Total operating revenues	689	857	3,417	3,998
Natural gas
Operating Expenses:
Total cost of sales	102	294	1,199	1,840
Other revenues
Operating Revenues:
Total operating revenues	222	178	662	519
Operating Expenses:
Total cost of sales	126	92	381	275
Fuel
Operating Expenses:
Total cost of sales	1,367	2,423	3,376	5,249
Purchased power
Operating Expenses:
Total cost of sales	207	645	680	1,285
SOUTHERN Co GAS
Operating Revenues:
Total operating revenues	$ 689	$ 857	$ 3,417	$ 3,998
Operating Expenses:
Cost, Product and Service [Extensible Enumeration]	Natural gas	Natural gas	Natural gas	Natural gas
Other operations and maintenance	$ 264	$ 252	$ 879	$ 824
Depreciation and amortization	145	140	429	414
Taxes other than income taxes	42	45	203	208
Total operating expenses	553	731	2,710	3,286
Operating Income	136	126	707	712
Other Income and (Expense):
Earnings from equity method investments	32	34	104	105
Interest expense, net of amounts capitalized	(77)	(65)	(226)	(187)
Other income (expense), net	19	15	50	47
Total other income and (expense)	(26)	(16)	(72)	(35)
Earnings Before Income Taxes	110	110	635	677
Income taxes	28	27	160	161
Net Income	82	83	475	516
SOUTHERN Co GAS | Natural gas
Operating Revenues:
Total operating revenues	689	857	3,417	3,998
Operating Expenses:
Total cost of sales	$ 102	$ 294	$ 1,199	$ 1,840