PROPERTY, PLANT, AND EQUIPMENT (Details) $ in Millions	Sep. 30, 2021 USD ($)
Columbia Energy Center Units 1 and 2
Property, Plant and Equipment [Line Items]
Net book value of plant to be retired	$ 279.3

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.

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