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Preferred Stock (Tables) | 12 Months Ended
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Dec. 31, 2018
Class of Stock [Line Items] |
Schedule of Carrying Value of Cumulative Preferred Stock | Information related to the carrying value of IPL’s cumulative preferred stock at December 31 was as follows:
Series |  | Liquidation Preference/Stated Value |  | Shares Authorized |  | Shares Outstanding |  | 2018 |  | 2017
|  |  |  |  |  |  |  | (in millions)
5.1% |  | $25 |  | 8,000,000 |  | 8,000,000 |  |  | $200.0 |  |  |  | $200.0 |
IPL [Member] |
Class of Stock [Line Items] |
Schedule of Carrying Value of Cumulative Preferred Stock | Information related to the carrying value of IPL’s cumulative preferred stock at December 31 was as follows:
Series |  | Liquidation Preference/Stated Value |  | Shares Authorized |  | Shares Outstanding |  | 2018 |  | 2017
|  |  |  |  |  |  |  | (in millions)
5.1% |  | $25 |  | 8,000,000 |  | 8,000,000 |  |  | $200.0 |  |  |  | $200.0 |

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- Definition Tabular disclosure of information pertaining to auction market preferred securities, including liquidation preference, liquidation value, par value, rate setting interval, redemption requirements, dividend distributions, roll forward of shares outstanding, shares authorized, aggregate value of auction market preferred securities, variable interest rate earned, and other information necessary to a fair presentation. If redeemable, the auction market preferred securities are redeemable solely at the option of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21488-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21484-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21564-112644 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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