Natural Gas Revenues

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- Definition

Number Of Natural Gas Distributions Utilities Sold

+ References

No definition available.

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- Definition

Number Of Pipeline Construction Projects

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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No definition available.

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- Definition

The number of states the entity operates in as of the balance sheet date.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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SEGMENT AND RELATED INFORMATION - Narrative (Details) $ in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2018 utility	Dec. 31, 2019 USD ($) state pipeline segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Total operating revenues		$ 21,419	$ 23,495	$ 23,031
Traditional Operating Companies
Segment Reporting Information [Line Items]
Number of states in which entity operates (states) \| state		3
Southern Power
Segment Reporting Information [Line Items]
Total operating revenues		$ 1,938	2,205	2,075
Southern Company Gas
Segment Reporting Information [Line Items]
Total operating revenues		$ 3,792	3,909	3,920
Number of states in which entity operates (states) \| state		4
Number of natural gas distribution utilities sold \| utility	3
Number of reportable segments \| segment		4
Southern Natural Gas Company, LLC \| Southern Company Gas
Segment Reporting Information [Line Items]
Ownership percentage, equity method investment		50.00%
Dalton Pipeline \| Southern Company Gas
Segment Reporting Information [Line Items]
Ownership percentage, equity method investment		50.00%
Southern Power \| Southern Company Gas
Segment Reporting Information [Line Items]
Natural gas revenues		$ 64	119	119
Traditional Electric Operating Companies \| Southern Company Gas
Segment Reporting Information [Line Items]
Natural gas revenues		14	32	23
Wholesale revenues, affiliates \| Southern Power
Segment Reporting Information [Line Items]
Total operating revenues		$ 398	$ 435	$ 392
Pipelines \| Southern Company Gas
Segment Reporting Information [Line Items]
Number of pipeline construction projects \| pipeline		2