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Income Taxes (Summary Of Tax Credit Carryforwards) (Details) $ in Millions | Sep. 30, 2022 USD ($)
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State [Member] |
Carryforwards [Line Items] |
Net operating losses, carryforward amount | $ 500
Federal [Member] |
Carryforwards [Line Items] |
Tax credits, carryforward amount | 655
IPL [Member] | State [Member] |
Carryforwards [Line Items] |
Net operating losses, carryforward amount | 9
IPL [Member] | Federal [Member] |
Carryforwards [Line Items] |
Tax credits, carryforward amount | 437
WPL [Member] | State [Member] |
Carryforwards [Line Items] |
Net operating losses, carryforward amount | 2
WPL [Member] | Federal [Member] |
Carryforwards [Line Items] |
Tax credits, carryforward amount | $ 208

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32559-109319 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32559-109319 + Details
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