v2.4.0.6

Selected Consolidated Quarterly Financial Data (Unaudited) (Tables) | 12 Months Ended
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Dec. 31, 2012
Components Of Selected Consolidated Quarterly Financial Data | Alliant Energy - All “per share” references refer to earnings per diluted share. Summation of the individual quarters may not equal annual totals due to rounding. Refer to Note 17 for additional information on discontinued operations.
| 2012 |  | 2011
| March 31 |  | June 30 |  | Sep. 30 |  | Dec. 31 |  | March 31 |  | June 30 |  | Sep. 30 |  | Dec. 31
| (in millions, except per share data)
Operating revenues |  | $765.7 |  |  |  | $690.3 |  |  |  | $887.6 |  |  |  | $750.9 |  |  |  | $877.2 |  |  |  | $712.5 |  |  |  | $870.9 |  |  |  | $760.8 |
Operating income | 95.6 |  |  | 108.8 |  |  | 213.7 |  |  | 101.6 |  |  | 127.3 |  |  | 70.6 |  |  | 209.4 |  |  | 106.0 |
Amounts attributable to Alliant Energy common shareowners: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income from continuing operations, net of tax | 39.3 |  |  | 65.5 |  |  | 149.0 |  |  | 71.1 |  |  | 72.0 |  |  | 50.3 |  |  | 136.9 |  |  | 63.9 |
Income (loss) from discontinued operations, net of tax | (4.4 | ) |  | 0.4 |  |  | 1.7 |  |  | (2.8 | ) |  | 1.5 |  |  | 0.8 |  |  | (14.9 | ) |  | (6.9 | )
Net income | 34.9 |  |  | 65.9 |  |  | 150.7 |  |  | 68.3 |  |  | 73.5 |  |  | 51.1 |  |  | 122.0 |  |  | 57.0 |
Earnings per weighted average common share attributable to Alliant Energy common shareowners: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income from continuing operations, net of tax | 0.36 |  |  | 0.60 |  |  | 1.34 |  |  | 0.64 |  |  | 0.65 |  |  | 0.45 |  |  | 1.23 |  |  | 0.58 |
Income (loss) from discontinued operations, net of tax | (0.04 | ) |  | — |  |  | 0.02 |  |  | (0.02 | ) |  | 0.01 |  |  | 0.01 |  |  | (0.13 | ) |  | (0.07 | )
Net income | 0.32 |  |  | 0.60 |  |  | 1.36 |  |  | 0.62 |  |  | 0.66 |  |  | 0.46 |  |  | 1.10 |  |  | 0.51 |
IPL [Member] |
Components Of Selected Consolidated Quarterly Financial Data | IPL - Earnings per share data is not disclosed for IPL given Alliant Energy is the sole shareowner of all shares of IPL’s common stock outstanding during the periods presented.
| 2012 |  | 2011
| March 31 |  | June 30 |  | Sep. 30 |  | Dec. 31 |  | March 31 |  | June 30 |  | Sep. 30 |  | Dec. 31
| (in millions)
Operating revenues |  | $398.7 |  |  |  | $360.7 |  |  |  | $497.7 |  |  |  | $393.2 |  |  |  | $477.5 |  |  |  | $374.1 |  |  |  | $484.5 |  |  |  | $404.0 |
Operating income | 23.9 |  |  | 35.4 |  |  | 112.0 |  |  | 29.0 |  |  | 47.1 |  |  | 18.5 |  |  | 116.5 |  |  | 26.3 |
Net income (loss) | (1.5 | ) |  | 19.6 |  |  | 106.5 |  |  | 25.6 |  |  | 27.1 |  |  | 1.0 |  |  | 101.4 |  |  | 9.8 |
Earnings available (loss) for common stock | (4.7 | ) |  | 16.6 |  |  | 103.3 |  |  | 22.4 |  |  | 21.7 |  |  | (2.3 | ) |  | 98.3 |  |  | 6.6 |
WPL [Member] |
Components Of Selected Consolidated Quarterly Financial Data | WPL - Earnings per share data is not disclosed for WPL given Alliant Energy is the sole shareowner of all shares of WPL’s common stock outstanding during the periods presented.
| 2012 |  | 2011
| March 31 |  | June 30 |  | Sep. 30 |  | Dec. 31 |  | March 31 |  | June 30 |  | Sep. 30 |  | Dec. 31
| (in millions)
Operating revenues |  | $354.5 |  |  |  | $315.7 |  |  |  | $376.6 |  |  |  | $345.2 |  |  |  | $388.5 |  |  |  | $326.8 |  |  |  | $374.6 |  |  |  | $344.5 |
Operating income | 64.6 |  |  | 61.5 |  |  | 93.4 |  |  | 65.3 |  |  | 74.8 |  |  | 45.5 |  |  | 86.9 |  |  | 73.2 |
Net income | 31.9 |  |  | 36.1 |  |  | 56.7 |  |  | 41.0 |  |  | 44.4 |  |  | 25.0 |  |  | 51.4 |  |  | 42.7 |
Earnings available for common stock | 31.1 |  |  | 35.2 |  |  | 55.9 |  |  | 40.2 |  |  | 43.6 |  |  | 24.1 |  |  | 50.6 |  |  | 41.9 |

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- Definition Tabular disclosure of the quarterly financial data in the annual financial statements. The disclosure includes financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income (loss) before extraordinary items and cumulative effect of a change in accounting principle and earnings per share data. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a)-(j) -URI http://asc.fasb.org/extlink&oid=20225539&loc=d3e1280-108306 + Details
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