Summary Of Significant Accounting Policies (Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2024 MW	Dec. 31, 2021 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Money market fund investments	$ 334		$ 334			$ 32
Money market fund investments interest rate, percentage	3.00%		3.00%
Distributions to noncontrolling interest			$ 29	$ 0
IPL [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Money market fund investments	$ 39		$ 39			32
Money market fund investments interest rate, percentage	3.00%		3.00%
WPL [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Money market fund investments	$ 295		$ 295			$ 0
Money market fund investments interest rate, percentage	3.00%		3.00%
WPL's cash contribution		$ 62
Tax equity partner's cash contribution		29
Contributed funds paid to WPL for equity interests		$ 88
Distributions to noncontrolling interest	$ 29		$ 29	$ 0
WPL [Member] | Solar [Member] | Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Nameplate capacity (in MW) | MW					1,100