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Commitments And Contingencies (Schedule Of Environmental Liabilities) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($)
Minimum range of estimated future cost incurred for investigation, remediation and monitoring | $ 11
Maximum remaining estimated cost incurred for investigation, remediation and monitoring | 30
IPL [Member] |
Minimum range of estimated future cost incurred for investigation, remediation and monitoring | 9
Maximum remaining estimated cost incurred for investigation, remediation and monitoring | 27
Manufactured Gas Plant [Member] |
Total environmental liabilities | 15
Manufactured Gas Plant [Member] | IPL [Member] |
Total environmental liabilities | $ 13

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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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