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Income Taxes (Summary Of Tax Credit Carryforwards) (Details) $ in Millions | Dec. 31, 2024 USD ($)
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State [Member] |
Tax carryforwards, net operating losses | $ 338
State [Member] | IPL [Member] |
Tax carryforwards, net operating losses | 7
State [Member] | WPL [Member] |
Tax carryforwards, net operating losses | 1
Federal [Member] |
Tax carryforwards, tax credits | 605
Federal [Member] | IPL [Member] |
Tax carryforwards, tax credits | 426
Federal [Member] | WPL [Member] |
Tax carryforwards, tax credits | $ 166

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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-3 + Details
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- Definition The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-3 + Details
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