Income tax

No definition available.

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- Definition

Tax Cuts and Jobs Act Of 2017 Change In Income Tax Expense Benefit

+ References

No definition available.

+ Details

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

+ Details

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax [Line Items]
Valuation allowance, reversal		$ 4
Income tax expense (benefits) Federal Tax Reform				$ (6)
Overall income tax rate		(10.00%)	11.00%	8.00%
IPL [Member]
Income Tax [Line Items]
Income tax expense (benefits) Federal Tax Reform				$ (1)
Overall income tax rate		(16.00%)	8.00%	(1.00%)
WPL [Member]
Income Tax [Line Items]
Income tax expense (benefits) Federal Tax Reform				$ (5)
Overall income tax rate		(8.00%)	17.00%	15.00%
State [Member]
Income Tax [Line Items]
Overall income tax rate		12.00%
State [Member] \| Forecast [Member]
Income Tax [Line Items]
Overall income tax rate	9.80%
State [Member] \| IPL [Member]
Income Tax [Line Items]
Overall income tax rate		12.00%
State [Member] \| IPL [Member] \| Forecast [Member]
Income Tax [Line Items]
Overall income tax rate	9.80%
State [Member] \| WPL [Member]
Income Tax [Line Items]
Overall income tax rate		12.00%
State [Member] \| WPL [Member] \| Forecast [Member]
Income Tax [Line Items]
Overall income tax rate	9.80%