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Receivables (Maximum And Average Outstanding Cash Proceeds) (Details) - IPL [Member] - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Maximum [Member] |  |  |
Accounts Receivable [Line Items] |  |  |
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 116.0 | $ 112.0 | $ 172.0
Average [Member] |  |  |
Accounts Receivable [Line Items] |  |  |
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 53.4 | $ 62.2 | $ 73.2

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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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- Definition The cash inflow associated with the proceeds from sale and collection of receivables during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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- Details
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