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Income Taxes (Summary Of Tax Credit Carryforwards) (Details) $ in Millions | Mar. 31, 2024 USD ($)
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State [Member] |
Carryforwards [Line Items] |
Net operating losses, carryforward amount | $ 403
Federal [Member] |
Carryforwards [Line Items] |
Tax credits, carryforward amount | 685
IPL [Member] | State [Member] |
Carryforwards [Line Items] |
Net operating losses, carryforward amount | 6
IPL [Member] | Federal [Member] |
Carryforwards [Line Items] |
Tax credits, carryforward amount | 462
WPL [Member] | State [Member] |
Carryforwards [Line Items] |
Net operating losses, carryforward amount | 1
WPL [Member] | Federal [Member] |
Carryforwards [Line Items] |
Tax credits, carryforward amount | $ 214

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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://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -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://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-3 + Details
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