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PROPERTY, PLANT, AND EQUIPMENT - Joint Ownership Agreements (Narrative) (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Property, Plant and Equipment [Line Items] |  |
Construction work in progress | $ 8,771 | $ 8,697
Georgia Power |  |
Property, Plant and Equipment [Line Items] |  |
Construction work in progress | $ 6,688 | $ 6,857
Plant Vogtle Units 3 and 4 | Georgia Power |  |
Property, Plant and Equipment [Line Items] |  |
Percent ownership | 45.70% |
Construction work in progress | $ 8,600 |

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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 + Details
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- Definition The proportionate share of interest (percent) in a jointly owned utility plant. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -URI http://asc.fasb.org/extlink&oid=122136288&loc=d3e659983-123033 + Details
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- Details
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