Estimated Future Construction Payments

No definition available.

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- Definition

Project Qualification for Production Tax Credits, Percentage

+ 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

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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+ Details

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
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Period Type:	instant

- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

+ References

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- Details

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- Details

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Acquisitions and Dispositions - Narrative (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended		12 Months Ended	36 Months Ended
	Apr. 11, 2018	Oct. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2017
Business Acquisition [Line Items]
Construction work in progress			$ 7,460				$ 6,904
Goodwill			6,226				6,268
SOUTHERN Co GAS
Business Acquisition [Line Items]
Construction work in progress			511				491
Goodwill impairment			42	$ 0
Goodwill			5,925				5,967
SOUTHERN POWER CO
Business Acquisition [Line Items]
Construction work in progress			634				511
Goodwill			2				$ 2
Series of Construction Projects \| SOUTHERN POWER CO
Business Acquisition [Line Items]
Construction work in progress			273
Series of Construction Projects \| Minimum \| SOUTHERN POWER CO
Business Acquisition [Line Items]
Estimated future construction payments			370
Series of Construction Projects \| Maximum \| SOUTHERN POWER CO
Business Acquisition [Line Items]
Estimated future construction payments			$ 415
Elizabethtown Gas and Elkton Gas \| SOUTHERN Co GAS
Business Acquisition [Line Items]
Aggregate purchase price		$ 1,700
Wind Generating Facility \| Scenario, Forecast \| SOUTHERN POWER CO
Business Acquisition [Line Items]
Project qualification for production tax credits, percentage					80.00%	100.00%
Pivotal Home Solutions \| Subsequent Event \| SOUTHERN Co GAS
Business Acquisition [Line Items]
Proceeds from divestiture of businesses	$ 365
Goodwill	$ 242