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Commitments And Contingencies (Narrative) (Details) $ in Millions | 12 Months Ended
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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

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