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Assets And Liabilities Held for Sale (Tables) | 3 Months Ended
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Mar. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |
Assets And Liabilities Held For Sale on Balance Sheets | Alliant Energy’s and IPL’s balance sheets included assets held for sale recorded in “Other current assets” and liabilities held for sale recorded in “Other current liabilities” as follows (in millions):
| March 31, 2015 |  | December 31, 2014
Assets held for sale: |  |  |
Current assets |  | $2.3 |  |  |  | $1.1 |
Property, plant and equipment, net | 11.0 |  |  | 11.0 |
Other assets | 6.4 |  |  | 7.0 |
Total assets held for sale | 19.7 |  |  | 19.1 |
Liabilities held for sale: |  |  |
Current liabilities | 0.2 |  |  | 1.0 |
Other liabilities | 6.8 |  |  | 7.1 |
Total liabilities held for sale | 7.0 |  |  | 8.1 |
Net assets held for sale |  | $12.7 |  |  |  | $11.0 |
IPL [Member] |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |
Assets And Liabilities Held For Sale on Balance Sheets | Alliant Energy’s and IPL’s balance sheets included assets held for sale recorded in “Other current assets” and liabilities held for sale recorded in “Other current liabilities” as follows (in millions):
| March 31, 2015 |  | December 31, 2014
Assets held for sale: |  |  |
Current assets |  | $2.3 |  |  |  | $1.1 |
Property, plant and equipment, net | 11.0 |  |  | 11.0 |
Other assets | 6.4 |  |  | 7.0 |
Total assets held for sale | 19.7 |  |  | 19.1 |
Liabilities held for sale: |  |  |
Current liabilities | 0.2 |  |  | 1.0 |
Other liabilities | 6.8 |  |  | 7.1 |
Total liabilities held for sale | 7.0 |  |  | 8.1 |
Net assets held for sale |  | $12.7 |  |  |  | $11.0 |

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