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Investments (Tables) | 9 Months Ended
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Sep. 30, 2020
Schedule of Equity Method Investments [Line Items] |
Unconsolidated Equity Investments | Alliant Energy’s 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):
| Three Months |  | Nine Months
| 2020 |  | 2019 |  | 2020 |  | 2019
ATC Holdings |  | ($11 | ) |  |  | ($11 | ) |  |  | ($36 | ) |  |  | ($30 | )
Non-utility wind farm in Oklahoma | (2 | ) |  | — |  |  | (6 | ) |  | (3 | )
Other | (2 | ) |  | (1 | ) |  | (4 | ) |  | (2 | )
|  | ($15 | ) |  |  | ($12 | ) |  |  | ($46 | ) |  |  | ($35 | )

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- Definition Tabular disclosure of equity method investments including, but not limited to, name of each investee or group of investments, percentage ownership, difference between recorded amount of an investment and the value of the underlying equity in the net assets, and summarized financial information. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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