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Investments | 3 Months Ended
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Mar. 31, 2017
Schedule of Investments [Line Items] |
Investments | INVESTMENTS NOTE 5(a) Unconsolidated Equity Investments - Equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions):
| Alliant Energy |  | WPL
| 2017 |  | 2016 |  | 2017 |  | 2016
ATC Investment |  | ($11.5 | ) |  |  | ($10.7 | ) |  |  | $— |  |  |  | ($10.7 | )
Other | — |  |  | 0.2 |  |  | — |  |  | — |
|  | ($11.5 | ) |  |  | ($10.5 | ) |  |  | $— |  |  |  | ($10.7 | )
On December 31, 2016, pursuant to a June 2016 PSCW order, WPL Transco, LLC was liquidated and WPL transferred its investment in ATC, LLC to ATI. As a result, WPL no longer records equity income from its prior investment in ATC, LLC. There were no impacts of this transfer to Alliant Energy’s consolidated financial statements. As of December 31, 2016, ATI owns Alliant Energy’s entire investment in ATC. NOTE 5(b) Cash Surrender Value of Life Insurance Policies - During the three months ended March 31, 2016, certain of Alliant Energy’s and IPL’s company-owned life insurance policies were liquidated. The related proceeds of $26 million and $18 million were recorded in investing activities in Alliant Energy’s and IPL’s cash flows statements, respectively.
IPL [Member] |
Schedule of Investments [Line Items] |
Investments | INVESTMENTS NOTE 5(a) Unconsolidated Equity Investments - Equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions):
| Alliant Energy |  | WPL
| 2017 |  | 2016 |  | 2017 |  | 2016
ATC Investment |  | ($11.5 | ) |  |  | ($10.7 | ) |  |  | $— |  |  |  | ($10.7 | )
Other | — |  |  | 0.2 |  |  | — |  |  | — |
|  | ($11.5 | ) |  |  | ($10.5 | ) |  |  | $— |  |  |  | ($10.7 | )
On December 31, 2016, pursuant to a June 2016 PSCW order, WPL Transco, LLC was liquidated and WPL transferred its investment in ATC, LLC to ATI. As a result, WPL no longer records equity income from its prior investment in ATC, LLC. There were no impacts of this transfer to Alliant Energy’s consolidated financial statements. As of December 31, 2016, ATI owns Alliant Energy’s entire investment in ATC. NOTE 5(b) Cash Surrender Value of Life Insurance Policies - During the three months ended March 31, 2016, certain of Alliant Energy’s and IPL’s company-owned life insurance policies were liquidated. The related proceeds of $26 million and $18 million were recorded in investing activities in Alliant Energy’s and IPL’s cash flows statements, respectively.
WPL [Member] |
Schedule of Investments [Line Items] |
Investments | INVESTMENTS NOTE 5(a) Unconsolidated Equity Investments - Equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions):
| Alliant Energy |  | WPL
| 2017 |  | 2016 |  | 2017 |  | 2016
ATC Investment |  | ($11.5 | ) |  |  | ($10.7 | ) |  |  | $— |  |  |  | ($10.7 | )
Other | — |  |  | 0.2 |  |  | — |  |  | — |
|  | ($11.5 | ) |  |  | ($10.5 | ) |  |  | $— |  |  |  | ($10.7 | )
On December 31, 2016, pursuant to a June 2016 PSCW order, WPL Transco, LLC was liquidated and WPL transferred its investment in ATC, LLC to ATI. As a result, WPL no longer records equity income from its prior investment in ATC, LLC. There were no impacts of this transfer to Alliant Energy’s consolidated financial statements. As of December 31, 2016, ATI owns Alliant Energy’s entire investment in ATC.

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