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Investments | 3 Months Ended
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Mar. 31, 2016
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
| 2016 |  | 2015 |  | 2016 |  | 2015
ATC |  | ($10.7 | ) |  |  | ($7.8 | ) |  |  | ($10.7 | ) |  |  | ($7.8 | )
Other | 0.2 |  |  | 1.3 |  |  | — |  |  | — |
|  | ($10.5 | ) |  |  | ($6.5 | ) |  |  | ($10.7 | ) |  |  | ($7.8 | )
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
| 2016 |  | 2015 |  | 2016 |  | 2015
ATC |  | ($10.7 | ) |  |  | ($7.8 | ) |  |  | ($10.7 | ) |  |  | ($7.8 | )
Other | 0.2 |  |  | 1.3 |  |  | — |  |  | — |
|  | ($10.5 | ) |  |  | ($6.5 | ) |  |  | ($10.7 | ) |  |  | ($7.8 | )
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
| 2016 |  | 2015 |  | 2016 |  | 2015
ATC |  | ($10.7 | ) |  |  | ($7.8 | ) |  |  | ($10.7 | ) |  |  | ($7.8 | )
Other | 0.2 |  |  | 1.3 |  |  | — |  |  | — |
|  | ($10.5 | ) |  |  | ($6.5 | ) |  |  | ($10.7 | ) |  |  | ($7.8 | )
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.

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- Definition The entire disclosure for investment holdings. This includes the long positions of investments for the entity. It contains investments in affiliated and unaffiliated issuers. The investments include securities and non securities (i.e. commodities and futures contracts). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-12C) -URI http://asc.fasb.org/extlink&oid=34726532&loc=d3e611225-123010 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14) -URI http://asc.fasb.org/extlink&oid=34726532&loc=d3e611322-123010 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 5 -Subparagraph (SX 210.12-13) -URI http://asc.fasb.org/extlink&oid=34726532&loc=d3e611282-123010 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12) -URI http://asc.fasb.org/extlink&oid=34726532&loc=d3e611133-123010 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 12 -Article 12 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 12C -Article 12 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 13 -Article 12 + Details
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