Property, Plant and Equipment (Narrative) (Details) - WPL [Member] $ in Millions	Mar. 31, 2024 USD ($) MW
Property, Plant and Equipment [Line Items]
Electric Capacity of Solar Project \| MW	1,100
Construction Project Cost Target Exceedance \| $	$ 180

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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