ACQUISITIONS AND DISPOSITIONS - Alabama Power Narrative (Details) - Alabama Power - Central Alabama Generating Station $ in Millions	Aug. 31, 2020 USD ($) MW
Business Acquisition [Line Items]
Approximate nameplate capacity (in MWs) \| MW	885
Purchase price	$ 461
Property, plant, and equipment	$ 452
Power sales agreement, remaining term	3 years

Approximate Nameplate Capacity

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- Definition

Power Sales Agreement, Remaining Term

+ References

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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

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
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- Definition

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

+ References

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-Name Accounting Standards Codification
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-SubTopic 20
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