v2.4.0.6

Investments (Tables) | 12 Months Ended
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Dec. 31, 2012
Investment [Line Items] |
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, 2012 |  | 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2010
Alliant Energy |  |  |  |  |  |  |  |  |  |  |
ATC (a) | 16% |  |  | $257.0 |  |  |  | $238.8 |  |  |  | ($41.3 | ) |  |  | ($37.8 | ) |  |  | ($36.9 | )
Wisconsin River Power Company | 50% |  | 7.3 |  |  | 7.7 |  |  | (0.8 | ) |  | (0.9 | ) |  | (0.9 | )
Other | Various |  | 2.3 |  |  | 3.1 |  |  | 0.8 |  |  | (0.6 | ) |  | (0.3 | )
|  |  |  | $266.6 |  |  |  | $249.6 |  |  |  | ($41.3 | ) |  |  | ($39.3 | ) |  |  | ($38.1 | )
WPL |  |  |  |  |  |  |  |  |  |  |
ATC (a) | 16% |  |  | $257.0 |  |  |  | $238.8 |  |  |  | ($41.3 | ) |  |  | ($37.8 | ) |  |  | ($36.9 | )
Wisconsin River Power Company | 50% |  | 7.3 |  |  | 7.7 |  |  | (0.8 | ) |  | (0.9 | ) |  | (0.9 | )
|  |  |  | $264.3 |  |  |  | $246.5 |  |  |  | ($42.1 | ) |  |  | ($38.7 | ) |  |  | ($37.8 | )
(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 19 for information regarding related party transactions with ATC.
Summary Financial Information | Summary aggregate financial information from the financial statements of these investments is as follows (in millions):
| Alliant Energy |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Operating revenues |  | $611 |  |  |  | $575 |  |  |  | $564 |  |  |  | $611 |  |  |  | $575 |  |  |  | $564 |
Operating income | 326 |  |  | 307 |  |  | 307 |  |  | 325 |  |  | 308 |  |  | 308 |
Net income | 234 |  |  | 218 |  |  | 226 |  |  | 239 |  |  | 226 |  |  | 221 |
As of December 31: |  |  |  |  |  |  |  |  |  |  |
Current assets | 67 |  |  | 62 |  |  |  |  | 66 |  |  | 61 |  |  |
Non-current assets | 3,321 |  |  | 3,100 |  |  |  |  | 3,292 |  |  | 3,071 |  |  |
Current liabilities | 252 |  |  | 299 |  |  |  |  | 252 |  |  | 299 |  |  |
Non-current liabilities | 1,652 |  |  | 1,490 |  |  |  |  | 1,651 |  |  | 1,487 |  |  |
Cash Surrender Value of Life Insurance Policies | At December 31, the cash surrender value of these investments was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Cash surrender value | $50.5 |  | $49.2 |  | $16.0 |  | $15.1 |  | $12.1 |  | $11.9
IPL [Member] |
Investment [Line Items] |
Cash Surrender Value of Life Insurance Policies | At December 31, the cash surrender value of these investments was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Cash surrender value | $50.5 |  | $49.2 |  | $16.0 |  | $15.1 |  | $12.1 |  | $11.9
WPL [Member] |
Investment [Line Items] |
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, 2012 |  | 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2010
Alliant Energy |  |  |  |  |  |  |  |  |  |  |
ATC (a) | 16% |  |  | $257.0 |  |  |  | $238.8 |  |  |  | ($41.3 | ) |  |  | ($37.8 | ) |  |  | ($36.9 | )
Wisconsin River Power Company | 50% |  | 7.3 |  |  | 7.7 |  |  | (0.8 | ) |  | (0.9 | ) |  | (0.9 | )
Other | Various |  | 2.3 |  |  | 3.1 |  |  | 0.8 |  |  | (0.6 | ) |  | (0.3 | )
|  |  |  | $266.6 |  |  |  | $249.6 |  |  |  | ($41.3 | ) |  |  | ($39.3 | ) |  |  | ($38.1 | )
WPL |  |  |  |  |  |  |  |  |  |  |
ATC (a) | 16% |  |  | $257.0 |  |  |  | $238.8 |  |  |  | ($41.3 | ) |  |  | ($37.8 | ) |  |  | ($36.9 | )
Wisconsin River Power Company | 50% |  | 7.3 |  |  | 7.7 |  |  | (0.8 | ) |  | (0.9 | ) |  | (0.9 | )
|  |  |  | $264.3 |  |  |  | $246.5 |  |  |  | ($42.1 | ) |  |  | ($38.7 | ) |  |  | ($37.8 | )
(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 19 for information regarding related party transactions with ATC.
Summary Financial Information | Summary aggregate financial information from the financial statements of these investments is as follows (in millions):
| Alliant Energy |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Operating revenues |  | $611 |  |  |  | $575 |  |  |  | $564 |  |  |  | $611 |  |  |  | $575 |  |  |  | $564 |
Operating income | 326 |  |  | 307 |  |  | 307 |  |  | 325 |  |  | 308 |  |  | 308 |
Net income | 234 |  |  | 218 |  |  | 226 |  |  | 239 |  |  | 226 |  |  | 221 |
As of December 31: |  |  |  |  |  |  |  |  |  |  |
Current assets | 67 |  |  | 62 |  |  |  |  | 66 |  |  | 61 |  |  |
Non-current assets | 3,321 |  |  | 3,100 |  |  |  |  | 3,292 |  |  | 3,071 |  |  |
Current liabilities | 252 |  |  | 299 |  |  |  |  | 252 |  |  | 299 |  |  |
Non-current liabilities | 1,652 |  |  | 1,490 |  |  |  |  | 1,651 |  |  | 1,487 |  |  |
Cash Surrender Value of Life Insurance Policies | At December 31, the cash surrender value of these investments was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Cash surrender value | $50.5 |  | $49.2 |  | $16.0 |  | $15.1 |  | $12.1 |  | $11.9

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- Definition Tabular disclosure of equity method investments in common stock. The disclosure may include: (a) the name of each investee or group of investments for which combined disclosure is appropriate, (2) the percentage ownership of common stock, (3) the difference, if any, between the carrying amount of an investment and the value of the underlying equity in the net assets and the accounting treatment of difference, if any, and (4) the aggregate value of each identified investment based on its quoted market price, if available. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 20 -Subparagraph a, b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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