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Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Commitments and Contingencies [Line Items]
Minimum future commitments			$ 1,931
Equity (income) loss from unconsolidated investments, net	$ 5	$ 13	37	$ 47
IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments			894
WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments			996
Capital Purchase Commitment [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments			208
Capital Purchase Commitment [Member] \| WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments			206
Indemnification Agreement [Member]
Commitments and Contingencies [Line Items]
Obligations, maximum	59		59
Indemnification Agreement [Member] \| Purchased Power [Member]
Commitments and Contingencies [Line Items]
Obligations, maximum	17		$ 17
Whiting Petroleum Affiliate [Member]
Commitments and Contingencies [Line Items]
Partnership share, percent			6.00%
Obligations, maximum	58		$ 58
Credit loss liability	5		5
Federal Energy Regulatory Commission [Member]
Commitments and Contingencies [Line Items]
MISO base return on equity, percentage					10.02%	9.88%
Equity (income) loss from unconsolidated investments, net	$ 5		$ 5