Concentration Risk Threshold Percentage

No definition available.

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- Definition

Indicates, if estimable, the approximate extent to which the proceeds from liquidation of any assets held either as collateral or by third parties would be expected to cover the maximum potential amount of future payments under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482425/460-10-50-4

+ Details

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Period Type:	duration

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482425/460-10-50-4

+ Details

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Period Type:	instant

- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482987/272-10-50-3

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

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- Details

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- Details

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Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2020	Dec. 31, 2019
Commitments and Contingencies [Line Items]
Minimum future commitments	$ 1,098
IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	497
WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	554
Capital Purchase Commitment [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	191
Capital Purchase Commitment [Member] \| IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	80
Capital Purchase Commitment [Member] \| WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	111
Indemnification Agreement [Member]
Commitments and Contingencies [Line Items]
Obligations, maximum	51
Indemnification Agreement [Member] \| Purchased Power [Member]
Commitments and Contingencies [Line Items]
Obligations, maximum	17
Indemnification Agreement [Member] \| Renewable Tax Credits Transferred [Member] \| IPL [Member]
Commitments and Contingencies [Line Items]
Indemnifications, renewable tax credit transfers	76
Indemnification Agreement [Member] \| Renewable Tax Credits Transferred [Member] \| WPL [Member]
Commitments and Contingencies [Line Items]
Indemnifications, renewable tax credit transfers	$ 22
Workforce Subject to Collective Bargaining Arrangements [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement, percentage	53.00%
Workforce Subject to Collective Bargaining Arrangements [Member] \| IPL [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement, percentage	70.00%
Workforce Subject to Collective Bargaining Arrangements [Member] \| WPL [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement, percentage	83.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement, percentage	18.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] \| IPL [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement, percentage	53.00%
Whiting Petroleum Affiliate [Member]
Commitments and Contingencies [Line Items]
Partnership share, percent	6.00%
Obligations, maximum	$ 49
Federal Energy Regulatory Commission [Member]
Commitments and Contingencies [Line Items]
MISO base return on equity, percentage		10.02%	9.88%