Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Long-term Purchase Commitment [Line Items]
Equity income from unconsolidated investments, net	$ 61	$ 51	$ 62
Workforce Subject to Collective Bargaining Arrangements [Member]
Long-term Purchase Commitment [Line Items]
Employees covered by collective bargaining agreement	53.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member]
Long-term Purchase Commitment [Line Items]
Employees covered by collective bargaining agreement	18.00%
Whiting Petroleum Affiliate [Member]
Long-term Purchase Commitment [Line Items]
Partnership share, percent	6.00%
Obligations, maximum	$ 49
Capital Purchase Commitment [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments	$ 188
IPL [Member] | Workforce Subject to Collective Bargaining Arrangements [Member]
Long-term Purchase Commitment [Line Items]
Employees covered by collective bargaining agreement	69.00%
IPL [Member] | Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member]
Long-term Purchase Commitment [Line Items]
Employees covered by collective bargaining agreement	53.00%
IPL [Member] | Capital Purchase Commitment [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments	$ 131
WPL [Member] | Workforce Subject to Collective Bargaining Arrangements [Member]
Long-term Purchase Commitment [Line Items]
Employees covered by collective bargaining agreement	83.00%
WPL [Member] | Capital Purchase Commitment [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments	$ 57
Indemnification Agreement [Member]
Long-term Purchase Commitment [Line Items]
Obligations, maximum	51
Indemnification Agreement [Member] | Purchased Power [Member]
Long-term Purchase Commitment [Line Items]
Obligations, maximum	17
Indemnification Agreement [Member] | Renewable Tax Credits Transferred [Member]
Long-term Purchase Commitment [Line Items]
Guarantor Obligations, Liquidation Proceeds, Monetary Amount	98
Indemnification Agreement [Member] | IPL [Member] | Renewable Tax Credits Transferred [Member]
Long-term Purchase Commitment [Line Items]
Guarantor Obligations, Liquidation Proceeds, Monetary Amount	76
Indemnification Agreement [Member] | WPL [Member] | Renewable Tax Credits Transferred [Member]
Long-term Purchase Commitment [Line Items]
Guarantor Obligations, Liquidation Proceeds, Monetary Amount	$ 22
FERC [Member]
Long-term Purchase Commitment [Line Items]
Base return on equity, percentage				10.02%	9.88%
Equity income from unconsolidated investments, net		$ 6