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Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Jun. 30, 2024
Commitments and Contingencies [Line Items] |  |  |
Minimum future commitments |  |  | $ 1,046
IPL [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Minimum future commitments |  |  | 472
WPL [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Minimum future commitments |  |  | $ 531
Workforce Subject to Collective Bargaining Arrangements [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Employees covered by collective bargaining agreement, percentage |  |  | 53.00%
Workforce Subject to Collective Bargaining Arrangements [Member] | IPL [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Employees covered by collective bargaining agreement, percentage |  |  | 70.00%
Workforce Subject to Collective Bargaining Arrangements [Member] | WPL [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Employees covered by collective bargaining agreement, percentage |  |  | 83.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Employees covered by collective bargaining agreement, percentage |  |  | 18.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] | IPL [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Employees covered by collective bargaining agreement, percentage |  |  | 54.00%
Federal Energy Regulatory Commission [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
MISO base return on equity, percentage | 10.02% | 9.88% |
Indemnification Agreement [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Obligations, maximum |  |  | $ 51
Whiting Petroleum Affiliate [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Partnership share, percent |  |  | 6.00%
Obligations, maximum |  |  | $ 49
Capital Purchase Commitment [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Minimum future commitments |  |  | 116
Capital Purchase Commitment [Member] | IPL [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Minimum future commitments |  |  | 38
Capital Purchase Commitment [Member] | WPL [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Minimum future commitments |  |  | 76
Purchased Power [Member] | Indemnification Agreement [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Obligations, maximum |  |  | 17
Renewable Tax Credits Transferred [Member] | Indemnification Agreement [Member] | IPL [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Obligations, maximum |  |  | 147
Renewable Tax Credits Transferred [Member] | Indemnification Agreement [Member] | WPL [Member] |  |  |
Commitments and Contingencies [Line Items] |  |  |
Obligations, maximum |  |  | $ 50

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- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482425/460-10-50-4 + Details
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