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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, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014
Receivables [Line Items] |  |  |  |
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 41.2 | $ 54.5 | $ 62.1 | $ 38.9
Maximum [Member] |  |  |  |
Receivables [Line Items] |  |  |  |
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 137.0 | $ 92.0 | $ 137.0 | $ 92.0

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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=31042434&loc=d3e3179-108585 + Details
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