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Investments | 12 Months Ended
--- | ---
Dec. 31, 2015
Schedule of Equity Method Investments [Line Items] |
Investments | INVESTMENTS (a) Unconsolidated Equity Investments - Alliant Energy’s and WPL’s unconsolidated investments accounted for under the equity method of accounting are as follows (in millions):
| Ownership |  | Carrying Value at |  |
| Interest at |  | December 31, |  | Equity (Income) / Loss
| December 31, 2015 |  | 2015 |  | 2014 |  | 2015 |  | 2014 |  | 2013
Alliant Energy |  |  |  |  |  |  |  |  |  |  |
ATC (a) | 16% |  |  | $293.3 |  |  |  | $286.5 |  |  |  | ($34.2 | ) |  |  | ($41.9 | ) |  |  | ($42.7 | )
Wisconsin River Power Company | 50% |  | 8.7 |  |  | 7.8 |  |  | (0.9 | ) |  | (0.9 | ) |  | (1.0 | )
Other | Various |  | 0.9 |  |  | 2.3 |  |  | 1.3 |  |  | 2.4 |  |  | — |
|  |  |  | $302.9 |  |  |  | $296.6 |  |  |  | ($33.8 | ) |  |  | ($40.4 | ) |  |  | ($43.7 | )
WPL |  |  |  |  |  |  |  |  |  |  |
ATC (a) | 16% |  |  | $293.3 |  |  |  | $286.5 |  |  |  | ($34.2 | ) |  |  | ($41.9 | ) |  |  | ($42.7 | )
Wisconsin River Power Company | 50% |  | 8.7 |  |  | 7.8 |  |  | (0.9 | ) |  | (0.9 | ) |  | (1.0 | )
|  |  |  | $302.0 |  |  |  | $294.3 |  |  |  | ($35.1 | ) |  |  | ($42.8 | ) |  |  | ($43.7 | )
(a) | Alliant Energy and WPL have the ability to exercise significant influence over ATC’s financial and operating policies through their participation on ATC’s Board of Directors. Refer to Note 18 for information regarding related party transactions with ATC.
Summary aggregate financial information from the financial statements of these investments is as follows (in millions):
| Alliant Energy |  | WPL
| 2015 |  | 2014 |  | 2013 |  | 2015 |  | 2014 |  | 2013
Operating revenues |  | $624 |  |  |  | $643 |  |  |  | $634 |  |  |  | $624 |  |  |  | $643 |  |  |  | $634 |
Operating income | 299 |  |  | 330 |  |  | 334 |  |  | 299 |  |  | 330 |  |  | 334 |
Net income | 186 |  |  | 240 |  |  | 248 |  |  | 202 |  |  | 240 |  |  | 250 |
As of December 31: |  |  |  |  |  |  |  |  |  |  |
Current assets | 88 |  |  | 72 |  |  |  |  | 87 |  |  | 70 |  |  |
Non-current assets | 3,987 |  |  | 3,773 |  |  |  |  | 3,977 |  |  | 3,747 |  |  |
Current liabilities | 332 |  |  | 315 |  |  |  |  | 332 |  |  | 315 |  |  |
Non-current liabilities | 2,052 |  |  | 1,871 |  |  |  |  | 2,052 |  |  | 1,870 |  |  |
MISO Transmission Owner Return on Equity Complaints - Complaints are currently pending with FERC regarding the level of return on equity that MISO transmission owners, including ATC, should be allowed to utilize in calculating the rates they charge their customers. Alliant Energy and WPL currently anticipate FERC’s decision on the MISO transmission owner complaints will reduce transmission owners’ current return on equity, which is expected to result in lower equity income and dividends from ATC in the future. In 2014, FERC issued an order on the complaints establishing an effective refund date of November 12, 2013. Alliant Energy and WPL have realized $15 million of reductions in the amount of equity income from ATC for the period from November 12, 2013 through December 31, 2015, including $12 million realized in 2015 and $3 million realized in 2014. WPL’s Noncontrolling Interest - Prior to 2014, WPL owned 100% of WPL Transco, which holds Alliant Energy’s investment in ATC. In 2014, WPL Transco’s operating agreement was amended to allow ATI, a wholly-owned subsidiary of Resources, to become a member of WPL Transco in addition to WPL. In 2014, ATI began funding capital contributions that WPL Transco makes to ATC. As of December 31, 2015, WPL’s and ATI’s ownership interests in WPL Transco were approximately 93% and 7%, respectively. WPL continues to consolidate WPL Transco and as a result, ATI’s ownership interest in WPL Transco was recorded as a noncontrolling interest in total equity on WPL’s balance sheets. In 2015 and 2014, WPL Transco’s equity income from ATC and ATC dividends received by WPL Transco were allocated between WPL and ATI based on their respective ownership interests at the time the equity income was generated and at the time of the dividend payments. ATI’s ownership interest in WPL Transco is expected to increase as a result of future capital contributions to WPL Transco. Alliant Energy’s aggregate ownership percentage in ATC is not expected to change as a result of WPL Transco’s amended operating agreement. (b) Cash Surrender Value of Life Insurance Policies - Various life insurance policies cover certain current and former employees and directors. At December 31, the cash surrender value of these investments was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2015 |  | 2014 |  | 2015 |  | 2014 |  | 2015 |  | 2014
Cash surrender value | $42.3 |  | $47.0 |  | $18.9 |  | $18.1 |  | $6.4 |  | $11.4
IPL [Member] |
Schedule of Equity Method Investments [Line Items] |
Investments | INVESTMENTS (b) Cash Surrender Value of Life Insurance Policies - Various life insurance policies cover certain current and former employees and directors. At December 31, the cash surrender value of these investments was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2015 |  | 2014 |  | 2015 |  | 2014 |  | 2015 |  | 2014
Cash surrender value | $42.3 |  | $47.0 |  | $18.9 |  | $18.1 |  | $6.4 |  | $11.4
WPL [Member] |
Schedule of Equity Method Investments [Line Items] |
Investments | INVESTMENTS (a) Unconsolidated Equity Investments - Alliant Energy’s and WPL’s unconsolidated investments accounted for under the equity method of accounting are as follows (in millions):
| Ownership |  | Carrying Value at |  |
| Interest at |  | December 31, |  | Equity (Income) / Loss
| December 31, 2015 |  | 2015 |  | 2014 |  | 2015 |  | 2014 |  | 2013
Alliant Energy |  |  |  |  |  |  |  |  |  |  |
ATC (a) | 16% |  |  | $293.3 |  |  |  | $286.5 |  |  |  | ($34.2 | ) |  |  | ($41.9 | ) |  |  | ($42.7 | )
Wisconsin River Power Company | 50% |  | 8.7 |  |  | 7.8 |  |  | (0.9 | ) |  | (0.9 | ) |  | (1.0 | )
Other | Various |  | 0.9 |  |  | 2.3 |  |  | 1.3 |  |  | 2.4 |  |  | — |
|  |  |  | $302.9 |  |  |  | $296.6 |  |  |  | ($33.8 | ) |  |  | ($40.4 | ) |  |  | ($43.7 | )
WPL |  |  |  |  |  |  |  |  |  |  |
ATC (a) | 16% |  |  | $293.3 |  |  |  | $286.5 |  |  |  | ($34.2 | ) |  |  | ($41.9 | ) |  |  | ($42.7 | )
Wisconsin River Power Company | 50% |  | 8.7 |  |  | 7.8 |  |  | (0.9 | ) |  | (0.9 | ) |  | (1.0 | )
|  |  |  | $302.0 |  |  |  | $294.3 |  |  |  | ($35.1 | ) |  |  | ($42.8 | ) |  |  | ($43.7 | )
(a) | Alliant Energy and WPL have the ability to exercise significant influence over ATC’s financial and operating policies through their participation on ATC’s Board of Directors. Refer to Note 18 for information regarding related party transactions with ATC.
Summary aggregate financial information from the financial statements of these investments is as follows (in millions):
| Alliant Energy |  | WPL
| 2015 |  | 2014 |  | 2013 |  | 2015 |  | 2014 |  | 2013
Operating revenues |  | $624 |  |  |  | $643 |  |  |  | $634 |  |  |  | $624 |  |  |  | $643 |  |  |  | $634 |
Operating income | 299 |  |  | 330 |  |  | 334 |  |  | 299 |  |  | 330 |  |  | 334 |
Net income | 186 |  |  | 240 |  |  | 248 |  |  | 202 |  |  | 240 |  |  | 250 |
As of December 31: |  |  |  |  |  |  |  |  |  |  |
Current assets | 88 |  |  | 72 |  |  |  |  | 87 |  |  | 70 |  |  |
Non-current assets | 3,987 |  |  | 3,773 |  |  |  |  | 3,977 |  |  | 3,747 |  |  |
Current liabilities | 332 |  |  | 315 |  |  |  |  | 332 |  |  | 315 |  |  |
Non-current liabilities | 2,052 |  |  | 1,871 |  |  |  |  | 2,052 |  |  | 1,870 |  |  |
MISO Transmission Owner Return on Equity Complaints - Complaints are currently pending with FERC regarding the level of return on equity that MISO transmission owners, including ATC, should be allowed to utilize in calculating the rates they charge their customers. Alliant Energy and WPL currently anticipate FERC’s decision on the MISO transmission owner complaints will reduce transmission owners’ current return on equity, which is expected to result in lower equity income and dividends from ATC in the future. In 2014, FERC issued an order on the complaints establishing an effective refund date of November 12, 2013. Alliant Energy and WPL have realized $15 million of reductions in the amount of equity income from ATC for the period from November 12, 2013 through December 31, 2015, including $12 million realized in 2015 and $3 million realized in 2014. WPL’s Noncontrolling Interest - Prior to 2014, WPL owned 100% of WPL Transco, which holds Alliant Energy’s investment in ATC. In 2014, WPL Transco’s operating agreement was amended to allow ATI, a wholly-owned subsidiary of Resources, to become a member of WPL Transco in addition to WPL. In 2014, ATI began funding capital contributions that WPL Transco makes to ATC. As of December 31, 2015, WPL’s and ATI’s ownership interests in WPL Transco were approximately 93% and 7%, respectively. WPL continues to consolidate WPL Transco and as a result, ATI’s ownership interest in WPL Transco was recorded as a noncontrolling interest in total equity on WPL’s balance sheets. In 2015 and 2014, WPL Transco’s equity income from ATC and ATC dividends received by WPL Transco were allocated between WPL and ATI based on their respective ownership interests at the time the equity income was generated and at the time of the dividend payments. ATI’s ownership interest in WPL Transco is expected to increase as a result of future capital contributions to WPL Transco. Alliant Energy’s aggregate ownership percentage in ATC is not expected to change as a result of WPL Transco’s amended operating agreement. (b) Cash Surrender Value of Life Insurance Policies - Various life insurance policies cover certain current and former employees and directors. At December 31, the cash surrender value of these investments was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2015 |  | 2014 |  | 2015 |  | 2014 |  | 2015 |  | 2014
Cash surrender value | $42.3 |  | $47.0 |  | $18.9 |  | $18.1 |  | $6.4 |  | $11.4

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