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Investments | 9 Months Ended
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Sep. 30, 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 and nine months ended September 30 was as follows (in millions):
| Alliant Energy |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2017 |  | 2016 |  | 2017 |  | 2016 |  | 2017 |  | 2016 |  | 2017 |  | 2016
ATC Investment |  | ($10.1 | ) |  |  | ($9.1 | ) |  |  | ($32.7 | ) |  |  | ($28.6 | ) |  |  | $— |  |  |  | ($9.1 | ) |  |  | $— |  |  |  | ($28.6 | )
Other | — |  |  | (0.1 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.4 | ) |  | (0.4 | )
|  | ($10.1 | ) |  |  | ($9.2 | ) |  |  | ($32.9 | ) |  |  | ($28.8 | ) |  |  | ($0.2 | ) |  |  | ($9.3 | ) |  |  | ($0.4 | ) |  |  | ($29.0 | )
ATC Investment - 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. Non-regulated Wind Investment in Oklahoma - In July 2017, a wholly-owned subsidiary of AEF acquired a 50% cash equity ownership interest in a 225 MW non-regulated wind farm located in Oklahoma, which started commercial operations in December 2016. The wind farm provides electricity to a third-party under a long-term purchased power agreement. In the third quarter of 2017, Alliant Energy’s “Other investments” assets increased $98 million from this acquisition. Alliant Energy will not maintain or operate the wind farm, and provided a parent guarantee of its subsidiary’s indemnification obligations under the operating agreement and purchased power agreement. Refer to Note 12(d) for discussion of the guarantee. Alliant Energy accounts for this non-regulated investment under the equity method of accounting, with the related equity (income) loss from unconsolidated investments included in the “Other” line in the above table. In conjunction with the acquisition, in July 2017, AEF entered into a $95 million, 364-day variable-rate term loan credit agreement (with Alliant Energy as guarantor). NOTE 5(b) Cash Surrender Value of Life Insurance Policies - During the nine months ended September 30, 2016, certain of Alliant Energy’s and IPL’s company-owned life insurance policies were liquidated. The related proceeds of $31 million and $19 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 and nine months ended September 30 was as follows (in millions):
| Alliant Energy |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2017 |  | 2016 |  | 2017 |  | 2016 |  | 2017 |  | 2016 |  | 2017 |  | 2016
ATC Investment |  | ($10.1 | ) |  |  | ($9.1 | ) |  |  | ($32.7 | ) |  |  | ($28.6 | ) |  |  | $— |  |  |  | ($9.1 | ) |  |  | $— |  |  |  | ($28.6 | )
Other | — |  |  | (0.1 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.4 | ) |  | (0.4 | )
|  | ($10.1 | ) |  |  | ($9.2 | ) |  |  | ($32.9 | ) |  |  | ($28.8 | ) |  |  | ($0.2 | ) |  |  | ($9.3 | ) |  |  | ($0.4 | ) |  |  | ($29.0 | )
ATC Investment - 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. Non-regulated Wind Investment in Oklahoma - In July 2017, a wholly-owned subsidiary of AEF acquired a 50% cash equity ownership interest in a 225 MW non-regulated wind farm located in Oklahoma, which started commercial operations in December 2016. The wind farm provides electricity to a third-party under a long-term purchased power agreement. In the third quarter of 2017, Alliant Energy’s “Other investments” assets increased $98 million from this acquisition. Alliant Energy will not maintain or operate the wind farm, and provided a parent guarantee of its subsidiary’s indemnification obligations under the operating agreement and purchased power agreement. Refer to Note 12(d) for discussion of the guarantee. Alliant Energy accounts for this non-regulated investment under the equity method of accounting, with the related equity (income) loss from unconsolidated investments included in the “Other” line in the above table. In conjunction with the acquisition, in July 2017, AEF entered into a $95 million, 364-day variable-rate term loan credit agreement (with Alliant Energy as guarantor). NOTE 5(b) Cash Surrender Value of Life Insurance Policies - During the nine months ended September 30, 2016, certain of Alliant Energy’s and IPL’s company-owned life insurance policies were liquidated. The related proceeds of $31 million and $19 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 and nine months ended September 30 was as follows (in millions):
| Alliant Energy |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2017 |  | 2016 |  | 2017 |  | 2016 |  | 2017 |  | 2016 |  | 2017 |  | 2016
ATC Investment |  | ($10.1 | ) |  |  | ($9.1 | ) |  |  | ($32.7 | ) |  |  | ($28.6 | ) |  |  | $— |  |  |  | ($9.1 | ) |  |  | $— |  |  |  | ($28.6 | )
Other | — |  |  | (0.1 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.4 | ) |  | (0.4 | )
|  | ($10.1 | ) |  |  | ($9.2 | ) |  |  | ($32.9 | ) |  |  | ($28.8 | ) |  |  | ($0.2 | ) |  |  | ($9.3 | ) |  |  | ($0.4 | ) |  |  | ($29.0 | )
ATC Investment - 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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