PROPERTY, PLANT, AND EQUIPMENT - PLANT TO BE RETIRED (Details) - WPS $ in Millions	Mar. 31, 2022 USD ($)
Columbia Energy Center Unit 1
Property, plant, and equipment
Net book value of plant to be retired	$ 87.9
Columbia Energy Center Unit 2
Property, plant, and equipment
Net book value of plant to be retired	$ 186.2

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