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v3.3.1.900

Consolidated Statements of Common Equity - USD ($) $ in Millions | Total | IPL [Member] | WPL [Member] | Common Stock [Member] | Common Stock [Member] IPL [Member] | Common Stock [Member] WPL [Member] | Additional Paid-in Capital [Member] | Additional Paid-in Capital [Member] IPL [Member] | Additional Paid-in Capital [Member] WPL [Member] | Retained Earnings [Member] | Retained Earnings [Member] IPL [Member] | Retained Earnings [Member] WPL [Member] | Accumulated Other Comprehensive Income (Loss) [Member] | Shares in Deferred Compensation Trust [Member] | Noncontrolling Interest [Member] WPL [Member]
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Beginning balance at Dec. 31, 2012 | $ 3,134.9 | $ 1,486.4 |  | $ 1.1 | $ 33.4 | $ 66.2 | $ 1,511.2 | $ 1,037.8 | $ 959.2 | $ 1,630.7 | $ 415.2 | $ 565.9 | $ (0.8) | $ (7.3) | $ 0.0
Beginning balance at Dec. 31, 2012 |  |  | $ 1,591.3 |  |  |  |  |  |  |  |  |  |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) attributable to common shareowners | 358.3 | 172.0 | 177.5 |  |  |  |  |  |  | 358.3 | 172.0 | 177.5 |  |  |
Net income | 376.2 | 188.3 | 179.1 |  |  |  |  |  |  |  |  |  |  |  |
Common stock dividends | (208.3) | (128.1) | (116.3) |  |  |  |  |  |  | (208.3) | (128.1) | (116.3) |  |  |
Common stock issued, net | 0.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital contributions from parent |  | 120.0 |  |  |  |  |  | 120.0 |  |  |  |  |  |  |
Preferred stock issuance costs | (5.4) | (5.4) |  |  |  |  | (5.4) | (5.4) |  |  |  |  |  |  |
Other | 1.3 | 3.2 | (5.1) |  |  |  | 2.0 | 0.4 | (0.2) |  | 2.8 | (4.9) |  | (0.7) |
Other comprehensive income (loss), net of tax | 0.6 | 0.0 | 0.0 |  |  |  |  |  |  |  |  |  | 0.6 |  |
Ending balance at Dec. 31, 2013 | 3,281.4 | 1,648.1 |  | 1.1 | 33.4 | 66.2 | 1,507.8 | 1,152.8 | 959.0 | 1,780.7 | 461.9 | 622.2 | (0.2) | (8.0) | 0.0
Ending balance at Dec. 31, 2013 |  |  | 1,647.4 |  |  |  |  |  |  |  |  |  |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) attributable to common shareowners | 383.1 | 181.6 | 180.4 |  |  |  |  |  |  | 383.1 | 181.6 | 180.4 |  |  | 0.7
Net income | 393.3 | 191.8 | 181.1 |  |  |  |  |  |  |  |  |  |  |  |
Common stock dividends | (225.8) | (140.0) | (118.7) |  |  |  |  |  |  | (225.8) | (140.0) | (118.7) |  |  |
Common stock issued, net | 0.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital contributions from parent |  | 90.0 |  |  |  |  |  | 90.0 |  |  |  |  |  |  |
Contributions from noncontrolling interest |  |  | 8.6 |  |  |  |  |  |  |  |  |  |  |  | 8.6
Distributions to noncontrolling interest |  |  | (0.8) |  |  |  |  |  |  |  |  |  |  |  | (0.8)
Other | 0.4 | 4.6 | (2.2) |  |  |  | 1.3 |  |  |  | 4.6 | (2.2) |  | (0.9) |
Other comprehensive income (loss), net of tax | (0.4) | 0.0 | 0.0 |  |  |  |  |  |  |  |  |  | (0.4) |  |
Ending balance at Dec. 31, 2014 | 3,438.7 | 1,784.3 | 1,706.9 | 1.1 | 33.4 | 66.2 | 1,509.1 | 1,242.8 | 959.0 | 1,938.0 | 508.1 | 681.7 | (0.6) | (8.9) | 8.5
Ending balance at Dec. 31, 2014 | 3,640.5 | 1,984.3 | 1,715.4 |  |  |  |  |  |  |  |  |  |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) attributable to common shareowners | 378.2 | 186.0 | 176.3 |  |  |  |  |  |  | 378.2 | 186.0 | 176.3 |  |  | 1.3
Net income | 388.4 | 196.2 | 177.6 |  |  |  |  |  |  |  |  |  |  |  |
Common stock dividends | (247.3) | (140.0) | (126.9) |  |  |  |  |  |  | (247.3) | (140.0) | (126.9) |  |  |
Common stock issued, net | 151.2 |  |  |  |  |  | 151.2 |  |  |  |  |  |  |  |
Capital contributions from parent |  | 165.0 |  |  |  |  |  | 165.0 |  |  |  |  |  |  |
Contributions from noncontrolling interest |  |  | 3.4 |  |  |  |  |  |  |  |  |  |  |  | 3.4
Distributions to noncontrolling interest |  |  | (1.9) |  |  |  |  |  |  |  |  |  |  |  | (1.9)
Other | 3.1 |  |  |  |  |  | 2.7 |  |  |  |  |  |  | 0.4 |
Other comprehensive income (loss), net of tax | 0.2 | 0.0 | 0.0 |  |  |  |  |  |  |  |  |  | 0.2 |  |
Ending balance at Dec. 31, 2015 | 3,724.1 | 1,995.3 | 1,756.3 | $ 1.1 | $ 33.4 | $ 66.2 | $ 1,663.0 | $ 1,407.8 | $ 959.0 | $ 2,068.9 | $ 554.1 | $ 731.1 | $ (0.4) | $ (8.5) | $ 11.3
Ending balance at Dec. 31, 2015 | $ 3,924.1 | $ 2,195.3 | $ 1,767.6 |  |  |  |  |  |  |  |  |  |  |  |

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