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Receivables (Maximum And Average Outstanding Cash Proceeds) (Details) - IPL [Member] - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2017 | Mar. 31, 2016
Receivables [Line Items] |  |
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 38.4 | $ 39.1
Maximum [Member] |  |
Receivables [Line Items] |  |
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 79.0 | $ 75.0

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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 -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: 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=66902209&loc=d3e3179-108585 + Details
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