PROPERTY, PLANT, AND EQUIPMENT - PLANT TO BE RETIRED (Details) $ in Millions	Jun. 30, 2025 USD ($)
WE \| OCPP
Property, plant, and equipment
Net book value of plant to be retired	$ 639.3
WPS \| Columbia Energy Center
Property, plant, and equipment
Net book value of plant to be retired	$ 243.4

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

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