Condensed Consolidated Statements of Income (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Operating revenues	$ 5,910	$ 5,018
Alternative revenue programs
Operating revenues	2	9
SOUTHERN Co GAS
Operating revenues	1,694	1,249
Revenue taxes collected	54	47
SOUTHERN Co GAS \| Alternative revenue programs
Operating revenues	$ 2	$ 9

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details