Income Taxes (Schedule Of Effective Income Tax Rates) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Effective Tax Rate [Line Items]
Overall income tax rate	(6.50%)	10.30%	(9.60%)	10.50%
IPL [Member]
Effective Tax Rate [Line Items]
Overall income tax rate	(6.50%)	3.80%	(13.80%)	3.70%
WPL [Member]
Effective Tax Rate [Line Items]
Overall income tax rate	(8.50%)	15.50%	(9.40%)	17.20%