v2.4.0.6

Discontinued Operations and Assets and Liabilities Held for Sale (Tables) | 12 Months Ended
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Dec. 31, 2012
Discontinued Operations and Disposal Groups [Abstract] |
Components Of Discontinued Operations In 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 | )
Assets and Liabilities Held For Sale on Consolidated Balance Sheets | 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 |

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- Definition Tabular disclosure of disposal groups, which may include 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 classification and carrying value of the assets and liabilities comprising the disposal group, and the segment in which the disposal group was reported. Also may include the amount of adjustments to amounts previously reported in discontinued operations such as resolution of contingencies arising from the disposal transaction or the operations of the component prior to disposal. + 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 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2443-110228 Reference 3: 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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 43, 44, 45, 47, 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 5: 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 6: 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 + Details
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