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Common Equity | 3 Months Ended
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Mar. 31, 2016
Common Equity [Line Items] |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2016 | 113,459,216 |
Shareowner Direct Plan issuances | 92,231 |
Equity-based compensation plans (Note 9(b)) | 11,204 |
Shares outstanding, March 31, 2016 | 113,562,651 |
Common Stock Split - On April 20, 2016, Alliant Energy’s Board of Directors approved a two-for-one common stock split and a proportionate increase in the number of shares of common stock of Alliant Energy from 240 million shares to 480 million shares to implement the stock split. Alliant Energy shareowners of record at the close of business on May 4, 2016 will receive one additional share of Alliant Energy common stock for each share held on that date. The proportionate interest that a shareowner owns in Alliant Energy will not change as a result of the stock split. The additional shares are expected to be distributed on May 19, 2016 and post-split trading is expected to begin on May 20, 2016. Based on common shares outstanding as of March 31, 2016, upon the completion of the stock split, Alliant Energy will have approximately 227 million shares of common stock outstanding. Except as disclosed in the pro forma EPS information below, all share and per share amounts for the three months ended March 31, 2016 and 2015 in this report have been reflected on a pre-split basis. The stock split will require all historical common stock shares and EPS data to be recast in the second quarter of 2016. For the three months ended March 31, pro forma basic and diluted EPS attributable to Alliant Energy common shareowners to reflect the two-for-one common stock split is as follows:
| 2016 |  | 2015
Basic and diluted EPS: |  |  |
As reported |  | $0.85 |  |  |  | $0.87 |
Pro forma | 0.43 |  |  | 0.43 |
Dividend Restrictions - As of March 31, 2016, IPL’s amount of retained earnings that were free of dividend restrictions was $562 million. As of March 31, 2016, WPL’s amount of retained earnings that were free of dividend restrictions was $101 million for the remainder of 2016. Restricted Net Assets of Subsidiaries - As of March 31, 2016, the amount of net assets of IPL and WPL that were not available to be transferred to their parent company, Alliant Energy, in the form of loans, advances or cash dividends without the consent of IPL’s and WPL’s regulatory authorities was $1.5 billion and $1.7 billion, respectively. Capital Transactions with Subsidiaries - For the three months ended March 31, 2016, IPL received capital contributions of $40.0 million from its parent company. For the three months ended March 31, 2016, IPL and WPL paid common stock dividends of $38.1 million and $33.8 million, respectively, to their parent company. Comprehensive Income - For the three months ended March 31, 2016 and 2015, Alliant Energy had no other comprehensive income; therefore, its comprehensive income was equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was equal to its net income attributable to Alliant Energy common shareowners for such periods. For the three months ended March 31, 2016 and 2015, IPL and WPL had no other comprehensive income; therefore, their comprehensive income was equal to their net income and their comprehensive income available for common stock was equal to their earnings available for common stock for such periods.
IPL [Member] |
Common Equity [Line Items] |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2016 | 113,459,216 |
Shareowner Direct Plan issuances | 92,231 |
Equity-based compensation plans (Note 9(b)) | 11,204 |
Shares outstanding, March 31, 2016 | 113,562,651 |
Common Stock Split - On April 20, 2016, Alliant Energy’s Board of Directors approved a two-for-one common stock split and a proportionate increase in the number of shares of common stock of Alliant Energy from 240 million shares to 480 million shares to implement the stock split. Alliant Energy shareowners of record at the close of business on May 4, 2016 will receive one additional share of Alliant Energy common stock for each share held on that date. The proportionate interest that a shareowner owns in Alliant Energy will not change as a result of the stock split. The additional shares are expected to be distributed on May 19, 2016 and post-split trading is expected to begin on May 20, 2016. Based on common shares outstanding as of March 31, 2016, upon the completion of the stock split, Alliant Energy will have approximately 227 million shares of common stock outstanding. Except as disclosed in the pro forma EPS information below, all share and per share amounts for the three months ended March 31, 2016 and 2015 in this report have been reflected on a pre-split basis. The stock split will require all historical common stock shares and EPS data to be recast in the second quarter of 2016. For the three months ended March 31, pro forma basic and diluted EPS attributable to Alliant Energy common shareowners to reflect the two-for-one common stock split is as follows:
| 2016 |  | 2015
Basic and diluted EPS: |  |  |
As reported |  | $0.85 |  |  |  | $0.87 |
Pro forma | 0.43 |  |  | 0.43 |
Dividend Restrictions - As of March 31, 2016, IPL’s amount of retained earnings that were free of dividend restrictions was $562 million. As of March 31, 2016, WPL’s amount of retained earnings that were free of dividend restrictions was $101 million for the remainder of 2016. Restricted Net Assets of Subsidiaries - As of March 31, 2016, the amount of net assets of IPL and WPL that were not available to be transferred to their parent company, Alliant Energy, in the form of loans, advances or cash dividends without the consent of IPL’s and WPL’s regulatory authorities was $1.5 billion and $1.7 billion, respectively. Capital Transactions with Subsidiaries - For the three months ended March 31, 2016, IPL received capital contributions of $40.0 million from its parent company. For the three months ended March 31, 2016, IPL and WPL paid common stock dividends of $38.1 million and $33.8 million, respectively, to their parent company. Comprehensive Income - For the three months ended March 31, 2016 and 2015, Alliant Energy had no other comprehensive income; therefore, its comprehensive income was equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was equal to its net income attributable to Alliant Energy common shareowners for such periods. For the three months ended March 31, 2016 and 2015, IPL and WPL had no other comprehensive income; therefore, their comprehensive income was equal to their net income and their comprehensive income available for common stock was equal to their earnings available for common stock for such periods.
WPL [Member] |
Common Equity [Line Items] |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2016 | 113,459,216 |
Shareowner Direct Plan issuances | 92,231 |
Equity-based compensation plans (Note 9(b)) | 11,204 |
Shares outstanding, March 31, 2016 | 113,562,651 |
Common Stock Split - On April 20, 2016, Alliant Energy’s Board of Directors approved a two-for-one common stock split and a proportionate increase in the number of shares of common stock of Alliant Energy from 240 million shares to 480 million shares to implement the stock split. Alliant Energy shareowners of record at the close of business on May 4, 2016 will receive one additional share of Alliant Energy common stock for each share held on that date. The proportionate interest that a shareowner owns in Alliant Energy will not change as a result of the stock split. The additional shares are expected to be distributed on May 19, 2016 and post-split trading is expected to begin on May 20, 2016. Based on common shares outstanding as of March 31, 2016, upon the completion of the stock split, Alliant Energy will have approximately 227 million shares of common stock outstanding. Except as disclosed in the pro forma EPS information below, all share and per share amounts for the three months ended March 31, 2016 and 2015 in this report have been reflected on a pre-split basis. The stock split will require all historical common stock shares and EPS data to be recast in the second quarter of 2016. For the three months ended March 31, pro forma basic and diluted EPS attributable to Alliant Energy common shareowners to reflect the two-for-one common stock split is as follows:
| 2016 |  | 2015
Basic and diluted EPS: |  |  |
As reported |  | $0.85 |  |  |  | $0.87 |
Pro forma | 0.43 |  |  | 0.43 |
Dividend Restrictions - As of March 31, 2016, IPL’s amount of retained earnings that were free of dividend restrictions was $562 million. As of March 31, 2016, WPL’s amount of retained earnings that were free of dividend restrictions was $101 million for the remainder of 2016. Restricted Net Assets of Subsidiaries - As of March 31, 2016, the amount of net assets of IPL and WPL that were not available to be transferred to their parent company, Alliant Energy, in the form of loans, advances or cash dividends without the consent of IPL’s and WPL’s regulatory authorities was $1.5 billion and $1.7 billion, respectively. Capital Transactions with Subsidiaries - For the three months ended March 31, 2016, IPL received capital contributions of $40.0 million from its parent company. For the three months ended March 31, 2016, IPL and WPL paid common stock dividends of $38.1 million and $33.8 million, respectively, to their parent company. Comprehensive Income - For the three months ended March 31, 2016 and 2015, Alliant Energy had no other comprehensive income; therefore, its comprehensive income was equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was equal to its net income attributable to Alliant Energy common shareowners for such periods. For the three months ended March 31, 2016 and 2015, IPL and WPL had no other comprehensive income; therefore, their comprehensive income was equal to their net income and their comprehensive income available for common stock was equal to their earnings available for common stock for such periods.

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