Estimated Future Construction Payments

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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.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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Acquisitions and Dispositions - Southern Power Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
Construction work in progress	$ 9,264		$ 9,264		$ 8,697
Gain on equipment contribution	11	$ 0	54	$ 39
SOUTHERN POWER CO
Business Acquisition [Line Items]
Construction work in progress	250		250		$ 127
Gain on equipment contribution	0	$ 0	39	$ 39
SOUTHERN POWER CO \| Series of Construction Projects
Business Acquisition [Line Items]
Construction work in progress	208		208
SOUTHERN POWER CO \| Series of Construction Projects \| Minimum
Business Acquisition [Line Items]
Estimated future construction payments	390		390
SOUTHERN POWER CO \| Series of Construction Projects \| Maximum
Business Acquisition [Line Items]
Estimated future construction payments	$ 460		$ 460