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Investments | 3 Months Ended
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Mar. 31, 2015
Schedule of Investments [Line Items] |
Investments | INVESTMENTS 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
| 2015 |  | 2014 |  | 2015 |  | 2014
ATC |  | ($7.8 | ) |  |  | ($11.2 | ) |  |  | ($7.8 | ) |  |  | ($11.2 | )
Other | 1.3 |  |  | (0.2 | ) |  | — |  |  | (0.2 | )
|  | ($6.5 | ) |  |  | ($11.4 | ) |  |  | ($7.8 | ) |  |  | ($11.4 | )
WPL [Member] |
Schedule of Investments [Line Items] |
Investments | INVESTMENTS 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
| 2015 |  | 2014 |  | 2015 |  | 2014
ATC |  | ($7.8 | ) |  |  | ($11.2 | ) |  |  | ($7.8 | ) |  |  | ($11.2 | )
Other | 1.3 |  |  | (0.2 | ) |  | — |  |  | (0.2 | )
|  | ($6.5 | ) |  |  | ($11.4 | ) |  |  | ($7.8 | ) |  |  | ($11.4 | )

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