Condensed Consolidated Statements of Income (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Total operating revenues	$ 6,159	$ 6,201	$ 18,158	$ 17,403
Alternative revenue programs
Total operating revenues	5	0	(23)	9
SOUTHERN Co GAS
Total operating revenues	492	565	2,861	2,841
Excise taxes collected	9	9	83	75
SOUTHERN Co GAS \| Alternative revenue programs
Total operating revenues	$ 5	$ 0	$ (23)	$ 9

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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