Income Taxes (Schedule Of Effective Income Tax Rates) (Details)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Effective Tax Rate [Line Items]
Overall income tax rate	(19.00%)	(12.00%)
IPL [Member]
Effective Tax Rate [Line Items]
Overall income tax rate	(17.00%)	(19.00%)
WPL [Member]
Effective Tax Rate [Line Items]
Overall income tax rate	(29.00%)	(10.00%)

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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