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Receivables (Maximum And Average Outstanding Cash Proceeds) (Details) - IPL [Member] - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Receivables [Line Items] |  |  |  |
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 66.2 | $ 112.3 | $ 58.7 | $ 91.5
Maximum [Member] |  |  |  |
Receivables [Line Items] |  |  |  |
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 112.0 | $ 172.0 | $ 112.0 | $ 172.0

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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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