Summary Of Significant Accounting Policies (Narrative) (Details) $ in Millions	6 Months Ended
Jun. 30, 2022 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
WPL's cash contribution	$ 62
Tax equity partner's cash contribution	29
Contributed funds paid to WPL for equity interests	$ 88

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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