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Commitments And Contingencies (MPG Site Estimated Future Costs And Recorded Liabilities) (Details) - Natural Gas Processing Plant [Member] $ in Millions | 9 Months Ended
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Sep. 30, 2023 USD ($)
Commitments and Contingencies [Line Items] |
Current and non-current environmental liabilities | $ 18
IPL [Member] |
Commitments and Contingencies [Line Items] |
Current and non-current environmental liabilities | 8
WPL [Member] |
Commitments and Contingencies [Line Items] |
Current and non-current environmental liabilities | 10
Minimum [Member] |
Commitments and Contingencies [Line Items] |
Range of estimated future costs | 9
Minimum [Member] | IPL [Member] |
Commitments and Contingencies [Line Items] |
Range of estimated future costs | 5
Minimum [Member] | WPL [Member] |
Commitments and Contingencies [Line Items] |
Range of estimated future costs | 4
Maximum [Member] |
Commitments and Contingencies [Line Items] |
Range of estimated future costs | 36
Maximum [Member] | IPL [Member] |
Commitments and Contingencies [Line Items] |
Range of estimated future costs | 11
Maximum [Member] | WPL [Member] |
Commitments and Contingencies [Line Items] |
Range of estimated future costs | $ 25

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- Definition Total anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property resulting from unanticipated contamination of the assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q4) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480102/450-20-S99-1 + Details
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