PROPERTY, PLANT, AND EQUIPMENT - Assets Subject to Lien (Narrative) (Details) $ in Millions	Dec. 31, 2021 USD ($)
Mississippi Power \| Chevron
Property, Plant and Equipment [Line Items]
Net book value of co-generation assets	$ 167

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.

No definition available.

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