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v3.6.0.2

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, 2013 |  | $ 3,281.4 | [1] | $ 1,648.1 |  | $ 2.2 | [1] | $ 33.4 | $ 66.2 | $ 1,506.7 | [1] | $ 1,152.8 | $ 959.0 | $ 1,780.7 | [1] | $ 461.9 | $ 622.2 | $ (0.2) | [1] | $ (8.0) | [1] | $ 0.0
Beginning 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) | [1] | (140.0) | (118.7) |  |  |  |  |  |  |  |  | (225.8) | [1] | (140.0) | (118.7) |  |  |  |  |
Common stock issued, net |  | 0.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital contributions from parent |  |  |  | 90.0 | 0.0 |  |  |  |  |  |  | 90.0 |  |  |  |  |  |  |  |  |  |
Contributions from noncontrolling interest |  |  |  |  | 8.6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8.6
Distributions to noncontrolling interest |  |  |  |  | (0.8) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (0.8)
Transfer of investment in ATC to ATI |  |  |  |  | 0.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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] | 1,784.3 |  | 2.2 | [1] | 33.4 | 66.2 | 1,508.0 | [1] | 1,242.8 | 959.0 | 1,938.0 | [1] | 508.1 | 681.7 | (0.6) | [1] | (8.9) | [1] | 8.5
Ending balance at Dec. 31, 2014 |  |  |  |  | 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) | [1] | (140.0) | (126.9) |  |  |  |  |  |  |  |  | (247.3) | [1] | (140.0) | (126.9) |  |  |  |  |
Common stock issued, net | [1] | 151.2 |  |  |  | 0.1 |  |  |  | 151.1 |  |  |  |  |  |  |  |  |  |  |  |
Capital contributions from parent |  |  |  | 165.0 | 0.0 |  |  |  |  |  |  | 165.0 |  |  |  |  |  |  |  |  |  |
Contributions from noncontrolling interest |  |  |  |  | 3.4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.4
Distributions to noncontrolling interest |  |  |  |  | (1.9) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (1.9)
Transfer of investment in ATC to ATI |  |  |  |  | 0.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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] | 1,995.3 | 1,756.3 | 2.3 | [1] | 33.4 | 66.2 | 1,661.8 | [1] | 1,407.8 | 959.0 | 2,068.9 | [1] | 554.1 | 731.1 | (0.4) | [1] | (8.5) | [1] | 11.3
Ending balance at Dec. 31, 2015 |  | 3,924.1 |  | 2,195.3 | 1,767.6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) attributable to common shareowners |  | 371.5 |  | 215.6 | 190.4 |  |  |  |  |  |  |  |  | 371.5 |  | 215.6 | 190.4 |  |  |  |  | 2.4
Net income |  | 381.7 |  | 225.8 | 192.8 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock dividends |  | (266.5) | [1] | (151.9) | (135.0) |  |  |  |  |  |  |  |  | (266.5) | [1] | (151.9) | (135.0) |  |  |  |  |
Common stock issued, net |  | 26.6 |  |  |  |  |  |  |  | 26.6 |  |  |  |  |  |  |  |  |  |  |  |
Capital contributions from parent |  |  |  | 190.0 | 60.0 |  |  |  |  |  |  | 190.0 | 60.0 |  |  |  |  |  |  |  |  |
Contributions from noncontrolling interest |  |  |  |  | 11.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11.5
Distributions to noncontrolling interest |  |  |  |  | (2.5) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (2.5)
Transfer of investment in ATC to ATI |  |  |  |  | (163.6) |  |  |  |  |  |  |  |  |  |  |  | (140.9) |  |  |  |  | (22.7)
Other |  | 6.3 |  |  |  |  |  |  |  | 4.7 |  |  |  | 3.1 |  |  |  |  |  | (1.5) |  |
Other comprehensive income (loss), net of tax |  | 0.0 |  | 0.0 | 0.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ending balance at Dec. 31, 2016 |  | 3,862.0 |  | 2,249.0 | 1,730.8 | $ 2.3 |  | $ 33.4 | $ 66.2 | $ 1,693.1 |  | $ 1,597.8 | $ 1,019.0 | $ 2,177.0 |  | $ 617.8 | $ 645.6 | $ (0.4) |  | $ (10.0) |  | $ 0.0
Ending balance at Dec. 31, 2016 |  | $ 4,062.0 |  | $ 2,449.0 | $ 1,730.8 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
[1] | Amounts reflect the effects of a two-for-one common stock split distributed in May 2016.

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