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Discontinued Operations and Assets and Liabilities Held For Sale | 12 Months Ended
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Dec. 31, 2012
Discontinued Operations and Disposal Groups [Abstract] |
Discontinued Operations | DISCONTINUED OPERATIONS AND ASSETS AND LIABILITIES HELD FOR SALE In 2011, Alliant Energy sold its IEA business to narrow its strategic focus and risk profile and received net proceeds of $5 million. In 2011, RMT sold its environmental business unit and received net proceeds of $12 million. In January 2013, Alliant Energy sold the remainder of its RMT business in order to narrow its strategic focus and risk profile. The final gain or loss from the sale of RMT is subject to a working capital adjustment and potential contingent consideration. Alliant Energy does not currently believe the final gain or loss related to the sale of RMT will be material. The RMT business qualified as assets and liabilities held for sale as of December 31, 2012. The operating results of RMT and IEA have been separately classified and reported as discontinued operations in Alliant Energy’s Consolidated Statements of Income. A summary of the components of discontinued operations in Alliant Energy’s Consolidated Statements of Income was as follows (in millions):
| 2012 |  | 2011 |  | 2010
Operating revenues |  | $289.2 |  |  |  | $445.0 |  |  |  | $160.3 |
Operating expenses | 297.0 |  |  | 476.9 |  |  | 166.8 |
Interest expense and other | 0.7 |  |  | — |  |  | 1.0 |
Loss before income taxes | (8.5 | ) |  | (31.9 | ) |  | (7.5 | )
Income tax benefit | (3.4 | ) |  | (12.4 | ) |  | (3.6 | )
Loss from discontinued operations, net of tax |  | ($5.1 | ) |  |  | ($19.5 | ) |  |  | ($3.9 | )
A summary of the assets and liabilities held for sale on Alliant Energy’s Consolidated Balance Sheets as of December 31 was as follows (in millions):
| 2012 |  | 2011
Assets held for sale: |  |  |
Property, plant and equipment, net |  | $— |  |  |  | $3.8 |
Current assets | 27.9 |  |  | 115.5 |
Other assets | — |  |  | 0.3 |
Total assets held for sale | 27.9 |  |  | 119.6 |
Liabilities held for sale: |  |  |
Current liabilities | 31.4 |  |  | 62.0 |
Other long-term liabilities and deferred credits | — |  |  | 0.1 |
Total liabilities held for sale | 31.4 |  |  | 62.1 |
Net assets (liabilities) held for sale |  | ($3.5 | ) |  |  | $57.5 |
Based on the terms of the January 2013 sale of RMT, the fair value of the business, less costs to sell, was not less than the carrying amount.

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- Definition The entire disclosure for the facts and circumstances leading to the completed or expected disposal, manner and timing of disposal, the gain (loss) recognized in the income statement and the income statement caption that includes that gain (loss), amounts of revenues and pretax profit or loss reported in discontinued operations, the segment in which the disposal group was reported, and the classification (whether sold or classified as held for sale) and carrying value of the assets and liabilities comprising the disposal group. Includes all disposal groups, including those classified as components of the entity (discontinued operations). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1474-107760 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 43-48 -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. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2443-110228 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1012-107759 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1510-107760 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1020-107759 + Details
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