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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, 2021 USD ($)
Commitments and Contingencies [Line Items] |
Current and non-current environmental liabilities | $ 12
IPL [Member] |
Commitments and Contingencies [Line Items] |
Current and non-current environmental liabilities | 9
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 | 6
Maximum [Member] |
Commitments and Contingencies [Line Items] |
Range of estimated future costs | 24
Maximum [Member] | IPL [Member] |
Commitments and Contingencies [Line Items] |
Range of estimated future costs | $ 19

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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q4) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
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- 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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- Details
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