XML 71 R51.htm IDEA: XBRL DOCUMENT
v3.24.1.u1

Income Taxes (Schedule Of Effective Income Tax Rates) (Details) | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Effective Tax Rate [Line Items] |  |
Overall income tax rate | (7.00%) | (1.00%)
IPL [Member] |  |
Effective Tax Rate [Line Items] |  |
Overall income tax rate | (19.00%) | (18.00%)
WPL [Member] |  |
Effective Tax Rate [Line Items] |  |
Overall income tax rate | 6.00% | 12.00%

X
- Definition Effective tax rate + References No definition available. + Details
Name: | lnt_EffectiveTaxRateLineItems
Namespace Prefix: | lnt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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 -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-12 + Details
Name: | us-gaap_EffectiveIncomeTaxRateContinuingOperations
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=lnt_IplMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=lnt_WplMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |