v2.4.0.6

Segments Of Business (Tables) | 12 Months Ended
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Dec. 31, 2012
Segment Reporting Information [Line Items] |
Schedule of Segments of Business | Certain financial information relating to Alliant Energy’s business segments, products and services and geographic information was as follows (in millions):
| Utility |  | Non-Regulated, |  | Alliant Energy
2012 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,589.3 |  |  |  | $396.3 |  |  |  | $56.7 |  |  |  | $3,042.3 |  |  |  | $52.2 |  |  |  | $3,094.5 |
Depreciation and amortization | 299.3 |  |  | 29.1 |  |  | 1.4 |  |  | 329.8 |  |  | 2.6 |  |  | 332.4 |
Operating income | 426.2 |  |  | 51.5 |  |  | 7.4 |  |  | 485.1 |  |  | 34.6 |  |  | 519.7 |
Interest expense, net of AFUDC |  |  |  |  |  |  | 136.8 |  |  | (2.0 | ) |  | 134.8 |
Equity (income) loss from unconsolidated investments, net | (42.1 | ) |  | — |  |  | — |  |  | (42.1 | ) |  | 0.8 |  |  | (41.3 | )
Interest income and other |  |  |  |  |  |  | (0.3 | ) |  | (3.7 | ) |  | (4.0 | )
Income taxes |  |  |  |  |  |  | 74.8 |  |  | 14.6 |  |  | 89.4 |
Income from continuing operations, net of tax |  |  |  |  |  |  | 315.9 |  |  | 24.9 |  |  | 340.8 |
Loss from discontinued operations, net of tax |  |  |  |  |  |  | — |  |  | (5.1 | ) |  | (5.1 | )
Net income |  |  |  |  |  |  | 315.9 |  |  | 19.8 |  |  | 335.7 |
Preferred dividends |  |  |  |  |  |  | 15.9 |  |  | — |  |  | 15.9 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 300.0 |  |  | 19.8 |  |  | 319.8 |
Total assets | 8,438.8 |  |  | 814.8 |  |  | 966.0 |  |  | 10,219.6 |  |  | 565.9 |  |  | 10,785.5 |
Investments in equity method subsidiaries | 264.3 |  |  | — |  |  | — |  |  | 264.3 |  |  | 2.3 |  |  | 266.6 |
Construction and acquisition expenditures | 994.0 |  |  | 31.4 |  |  | 0.1 |  |  | 1,025.5 |  |  | 132.6 |  |  | 1,158.1 |
| Utility |  | Non-Regulated, |  | Alliant Energy
2011 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,635.8 |  |  |  | $476.7 |  |  |  | $62.0 |  |  |  | $3,174.5 |  |  |  | $46.9 |  |  |  | $3,221.4 |
Depreciation and amortization | 289.0 |  |  | 28.4 |  |  | 1.8 |  |  | 319.2 |  |  | 1.8 |  |  | 321.0 |
Operating income (loss) | 444.2 |  |  | 47.8 |  |  | (3.2 | ) |  | 488.8 |  |  | 24.5 |  |  | 513.3 |
Interest expense, net of AFUDC |  |  |  |  |  |  | 146.6 |  |  | (0.3 | ) |  | 146.3 |
Equity income from unconsolidated investments, net | (38.7 | ) |  | — |  |  | — |  |  | (38.7 | ) |  | (0.6 | ) |  | (39.3 | )
Interest income and other |  |  |  |  |  |  | (0.2 | ) |  | (4.1 | ) |  | (4.3 | )
Income tax expense (benefit) |  |  |  |  |  |  | 78.3 |  |  | (9.1 | ) |  | 69.2 |
Income from continuing operations, net of tax |  |  |  |  |  |  | 302.8 |  |  | 38.6 |  |  | 341.4 |
Loss from discontinued operations, net of tax |  |  |  |  |  |  | — |  |  | (19.5 | ) |  | (19.5 | )
Net income |  |  |  |  |  |  | 302.8 |  |  | 19.1 |  |  | 321.9 |
Preferred dividends |  |  |  |  |  |  | 18.3 |  |  | — |  |  | 18.3 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 284.5 |  |  | 19.1 |  |  | 303.6 |
Total assets | 7,524.5 |  |  | 831.9 |  |  | 781.1 |  |  | 9,137.5 |  |  | 550.4 |  |  | 9,687.9 |
Investments in equity method subsidiaries | 246.5 |  |  | — |  |  | — |  |  | 246.5 |  |  | 3.1 |  |  | 249.6 |
Construction and acquisition expenditures | 542.7 |  |  | 38.0 |  |  | 27.4 |  |  | 608.1 |  |  | 65.3 |  |  | 673.4 |
| Utility |  | Non-Regulated, |  | Alliant Energy
2010 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,674.2 |  |  |  | $480.6 |  |  |  | $64.6 |  |  |  | $3,219.4 |  |  |  | $42.7 |  |  |  | $3,262.1 |
Depreciation and amortization | 255.1 |  |  | 25.2 |  |  | 5.3 |  |  | 285.6 |  |  | 1.7 |  |  | 287.3 |
Operating income (loss) | 489.8 |  |  | 53.4 |  |  | (2.5 | ) |  | 540.7 |  |  | 19.3 |  |  | 560.0 |
Interest expense, net of AFUDC |  |  |  |  |  |  | 142.8 |  |  | 2.0 |  |  | 144.8 |
Equity income from unconsolidated investments, net | (37.8 | ) |  | — |  |  | — |  |  | (37.8 | ) |  | (0.3 | ) |  | (38.1 | )
Interest income and other |  |  |  |  |  |  | (0.6 | ) |  | (4.0 | ) |  | (4.6 | )
Income taxes |  |  |  |  |  |  | 140.6 |  |  | 7.1 |  |  | 147.7 |
Income from continuing operations, net of tax |  |  |  |  |  |  | 295.7 |  |  | 14.5 |  |  | 310.2 |
Loss from discontinued operations, net of tax |  |  |  |  |  |  | — |  |  | (3.9 | ) |  | (3.9 | )
Net income |  |  |  |  |  |  | 295.7 |  |  | 10.6 |  |  | 306.3 |
Preferred dividends |  |  |  |  |  |  | 18.7 |  |  | — |  |  | 18.7 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 277.0 |  |  | 10.6 |  |  | 287.6 |
Total assets | 7,227.2 |  |  | 817.6 |  |  | 782.4 |  |  | 8,827.2 |  |  | 455.7 |  |  | 9,282.9 |
Investments in equity method subsidiaries | 236.0 |  |  | — |  |  | — |  |  | 236.0 |  |  | 2.5 |  |  | 238.5 |
Construction and acquisition expenditures | 729.1 |  |  | 39.9 |  |  | 64.3 |  |  | 833.3 |  |  | 33.6 |  |  | 866.9 |
Schedule of Products and Services | Products and Services - Alliant Energy’s consolidated operating revenues by segment were as follows:
| 2012 |  | 2011 |  | 2010
Utility electric operations | 84 | % |  | 82 | % |  | 82 | %
Utility gas operations | 13 | % |  | 15 | % |  | 15 | %
Utility other | 2 | % |  | 2 | % |  | 2 | %
Other | 1 | % |  | 1 | % |  | 1 | %
| 100 | % |  | 100 | % |  | 100 | %
IPL [Member] |
Segment Reporting Information [Line Items] |
Schedule of Segments of Business | Certain financial information relating to IPL’s business segments was as follows (in millions):
2012 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,371.1 |  |  |  | $226.7 |  |  |  | $52.5 |  |  |  | $1,650.3 |
Depreciation and amortization | 171.2 |  |  | 16.3 |  |  | 1.4 |  |  | 188.9 |
Operating income | 166.2 |  |  | 24.2 |  |  | 9.9 |  |  | 200.3 |
Interest expense, net of AFUDC |  |  |  |  |  |  | 70.1 |
Interest income and other |  |  |  |  |  |  | (0.2 | )
Income tax benefit |  |  |  |  |  |  | (19.8 | )
Net income |  |  |  |  |  |  | 150.2 |
Preferred dividends |  |  |  |  |  |  | 12.6 |
Earnings available for common stock |  |  |  |  |  |  | 137.6 |
Total assets | 4,500.9 |  |  | 479.5 |  |  | 476.6 |  |  | 5,457.0 |
Construction and acquisition expenditures | 291.0 |  |  | 16.4 |  |  | 0.1 |  |  | 307.5 |
2011 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,408.3 |  |  |  | $276.3 |  |  |  | $55.5 |  |  |  | $1,740.1 |
Depreciation and amortization | 161.3 |  |  | 16.0 |  |  | 1.8 |  |  | 179.1 |
Operating income | 181.6 |  |  | 20.6 |  |  | 6.2 |  |  | 208.4 |
Interest expense, net of AFUDC |  |  |  |  |  |  | 72.9 |
Interest income and other |  |  |  |  |  |  | (0.2 | )
Income tax benefit |  |  |  |  |  |  | (3.6 | )
Net income |  |  |  |  |  |  | 139.3 |
Preferred dividends |  |  |  |  |  |  | 15.0 |
Earnings available for common stock |  |  |  |  |  |  | 124.3 |
Total assets | 4,208.2 |  |  | 471.1 |  |  | 414.2 |  |  | 5,093.5 |
Construction and acquisition expenditures | 245.6 |  |  | 21.2 |  |  | 26.9 |  |  | 293.7 |
2010 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,464.3 |  |  |  | $274.3 |  |  |  | $57.2 |  |  | $1,795.8
Depreciation and amortization | 157.1 |  |  | 14.6 |  |  | 5.3 |  |  | 177.0 |
Operating income (loss) | 239.7 |  |  | 23.6 |  |  | (1.4 | ) |  | 261.9 |
Interest expense, net of AFUDC |  |  |  |  |  |  | 76.7 |
Interest income and other |  |  |  |  |  |  | (0.5 | )
Income taxes |  |  |  |  |  |  | 42.3 |
Net income |  |  |  |  |  |  | 143.4 |
Preferred dividends |  |  |  |  |  |  | 15.4 |
Earnings available for common stock |  |  |  |  |  |  | 128.0 |
Total assets | 4,025.3 |  |  | 460.3 |  |  | 452.0 |  |  | 4,937.6 |
Construction and acquisition expenditures | 298.8 |  |  | 20.0 |  |  | 64.0 |  |  | 382.8 |
WPL [Member] |
Segment Reporting Information [Line Items] |
Schedule of Segments of Business | Certain financial information relating to WPL’s business segments was as follows (in millions):
2012 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,218.2 |  |  |  | $169.6 |  |  |  | $4.2 |  |  |  | $1,392.0 |
Depreciation and amortization | 128.1 |  |  | 12.8 |  |  | — |  |  | 140.9 |
Operating income (loss) | 260.0 |  |  | 27.3 |  |  | (2.5 | ) |  | 284.8 |
Interest expense, net of AFUDC |  |  |  |  |  |  | 66.7 |
Equity income from unconsolidated investments | (42.1 | ) |  | — |  |  | — |  |  | (42.1 | )
Interest income and other |  |  |  |  |  |  | (0.1 | )
Income taxes |  |  |  |  |  |  | 94.6 |
Net income |  |  |  |  |  |  | 165.7 |
Preferred dividends |  |  |  |  |  |  | 3.3 |
Earnings available for common stock |  |  |  |  |  |  | 162.4 |
Total assets | 3,937.9 |  |  | 335.3 |  |  | 489.4 |  |  | 4,762.6 |
Investments in equity method subsidiaries | 264.3 |  |  | — |  |  | — |  |  | 264.3 |
Construction and acquisition expenditures | 703.0 |  |  | 15.0 |  |  | — |  |  | 718.0 |
2011 | Electric |  | Gas |  | Other |  | Total
Operating revenues | $1,227.5 |  |  | $200.4 |  |  |  | $6.5 |  |  |  | $1,434.4 |
Depreciation and amortization | 127.7 |  | 12.4 |  | — |  | 140.1 |
Operating income (loss) | 262.6 |  | 27.2 |  | (9.4) |  | 280.4 |
Interest expense, net of AFUDC |  |  |  |  |  |  | 73.7 |
Equity income from unconsolidated investments | (38.7) |  | — |  | — |  | (38.7 | )
Income taxes |  |  |  |  |  |  | 81.9 |
Net income |  |  |  |  |  |  | 163.5 |
Preferred dividends |  |  |  |  |  |  | 3.3 |
Earnings available for common stock |  |  |  |  |  |  | 160.2 |
Total assets | 3,316.3 |  | 360.8 |  | 366.9 |  | 4,044.0 |
Investments in equity method subsidiaries | 246.5 |  | — |  | — |  | 246.5 |
Construction and acquisition expenditures | 297.1 |  | 16.8 |  | 0.5 |  | 314.4 |
2010 | Electric |  | Gas |  | Other |  | Total
Operating revenues | $1,209.9 |  |  | $206.3 |  |  |  | $7.4 |  |  |  | $1,423.6 |
Depreciation and amortization | 98.0 |  | 10.6 |  | — |  | 108.6 |
Operating income (loss) | 250.1 |  | 29.8 |  | (1.1) |  | 278.8 |
Interest expense, net of AFUDC |  |  |  |  |  |  | 66.1 |
Equity income from unconsolidated investments | (37.8) |  | — |  | — |  | (37.8 | )
Interest income and other |  |  |  |  |  |  | (0.1 | )
Income taxes |  |  |  |  |  |  | 98.3 |
Net income |  |  |  |  |  |  | 152.3 |
Preferred dividends |  |  |  |  |  |  | 3.3 |
Earnings available for common stock |  |  |  |  |  |  | 149.0 |
Total assets | 3,201.9 |  | 357.3 |  | 330.4 |  | 3,889.6 |
Investments in equity method subsidiaries | 236.0 |  | — |  | — |  | 236.0 |
Construction and acquisition expenditures | 430.3 |  | 19.9 |  |  | 0.3 |  |  | 450.5 |

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