ACQUISITIONS AND DISPOSITIONS - Southern Company Gas Narrative (Details) - SOUTHERN Co GAS $ in Millions	Mar. 24, 2020 USD ($) payment
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Pivotal Home Solutions
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses, net of cash divested	$ 178
Pivotal LNG and Atlantic Coast Pipeline
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of contingent milestone payments \| payment	2
Contingent milestone payment, amount	$ 5

Disposal Group, Not Discontinued Operation, Contingent Milestone Payment, Amount

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- Definition

Disposal Group, Not Discontinued Operation, Number Of Contingent Milestone Payments

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

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