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Investments | 3 Months Ended
--- | ---
Mar. 31, 2013
Schedule of Equity Method Investments [Line Items] |
Investments | INVESTMENTS Unconsolidated Equity Investments - Equity (income) loss from Alliant Energy’s and WPL’s 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
| 2013 |  | 2012 |  | 2013 |  | 2012
American Transmission Company LLC (ATC) |  | ($10.3 | ) |  |  | ($9.9 | ) |  |  | ($10.3 | ) |  |  | ($9.9 | )
Other | (0.4 | ) |  | 0.5 |  |  | (0.5 | ) |  | (0.2 | )
|  | ($10.7 | ) |  |  | ($9.4 | ) |  |  | ($10.8 | ) |  |  | ($10.1 | )
Summary financial information from the unaudited financial statements of ATC for the three months ended March 31 was as follows (in millions):
| 2013 |  | 2012
Operating revenues | $151.7 |  | $147.7
Operating income | 82.0 |  | 78.1
Net income | 60.5 |  | 58.1
WPL [Member] |
Schedule of Equity Method Investments [Line Items] |
Investments | INVESTMENTS Unconsolidated Equity Investments - Equity (income) loss from Alliant Energy’s and WPL’s 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
| 2013 |  | 2012 |  | 2013 |  | 2012
American Transmission Company LLC (ATC) |  | ($10.3 | ) |  |  | ($9.9 | ) |  |  | ($10.3 | ) |  |  | ($9.9 | )
Other | (0.4 | ) |  | 0.5 |  |  | (0.5 | ) |  | (0.2 | )
|  | ($10.7 | ) |  |  | ($9.4 | ) |  |  | ($10.8 | ) |  |  | ($10.1 | )
Summary financial information from the unaudited financial statements of ATC for the three months ended March 31 was as follows (in millions):
| 2013 |  | 2012
Operating revenues | $151.7 |  | $147.7
Operating income | 82.0 |  | 78.1
Net income | 60.5 |  | 58.1

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