Commitments And Contingencies (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)
Workforce Subject to Collective Bargaining Arrangements [Member]
Long-term Purchase Commitment [Line Items]
Employees covered by collective bargaining agreement	54.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member]
Long-term Purchase Commitment [Line Items]
Employees covered by collective bargaining agreement	26.00%
Whiting Petroleum Affiliate [Member]
Long-term Purchase Commitment [Line Items]
Partnership share, percent	6.00%
Obligations, maximum	$ 60
Credit loss liability	5
Capital Purchase Commitment [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments	$ 178
IPL [Member] | Workforce Subject to Collective Bargaining Arrangements [Member]
Long-term Purchase Commitment [Line Items]
Employees covered by collective bargaining agreement	69.00%
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] | Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [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	$ 177
Indemnification Agreement [Member]
Long-term Purchase Commitment [Line Items]
Obligations, maximum	67
Indemnification Agreement [Member] | Purchased Power [Member]
Long-term Purchase Commitment [Line Items]
Obligations, maximum	$ 17