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Common Equity | 9 Months Ended
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Sep. 30, 2017
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, 2017 | 227,673,654 |
At-the-market offering program | 3,074,931 |
Shareowner Direct Plan issuances | 496,437 |
Equity-based compensation plans (Note 9(b)) | 5,185 |
Other | (45,847 | )
Shares outstanding, September 30, 2017 | 231,204,360 |
At-the-Market Offering Program - In May 2017, Alliant Energy filed a prospectus supplement under which it could sell up to $125 million of its common stock through an at-the-market offering program. As of September 30, 2017, Alliant Energy issued 3,074,931 shares of common stock through this program and received cash proceeds of $124 million, net of $1 million in commissions and fees. The proceeds from the issuances of common stock were used for general corporate purposes. Alliant Energy currently has no plans to issue any additional common stock through this at-the-market offering program. Dividend Restrictions - As of September 30, 2017, IPL’s amount of retained earnings that were free of dividend restrictions was $701 million. As of September 30, 2017, WPL’s amount of retained earnings that were free of dividend restrictions was $32 million for the remainder of 2017. Restricted Net Assets of Subsidiaries - As of September 30, 2017, the amount of IPL’s and WPL’s net assets 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 $1.7 billion and $1.8 billion, respectively. Comprehensive Income - For the three and nine months ended September 30, 2017 and 2016, 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 and nine months ended September 30, 2017 and 2016, 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, 2017 | 227,673,654 |
At-the-market offering program | 3,074,931 |
Shareowner Direct Plan issuances | 496,437 |
Equity-based compensation plans (Note 9(b)) | 5,185 |
Other | (45,847 | )
Shares outstanding, September 30, 2017 | 231,204,360 |
At-the-Market Offering Program - In May 2017, Alliant Energy filed a prospectus supplement under which it could sell up to $125 million of its common stock through an at-the-market offering program. As of September 30, 2017, Alliant Energy issued 3,074,931 shares of common stock through this program and received cash proceeds of $124 million, net of $1 million in commissions and fees. The proceeds from the issuances of common stock were used for general corporate purposes. Alliant Energy currently has no plans to issue any additional common stock through this at-the-market offering program. Dividend Restrictions - As of September 30, 2017, IPL’s amount of retained earnings that were free of dividend restrictions was $701 million. As of September 30, 2017, WPL’s amount of retained earnings that were free of dividend restrictions was $32 million for the remainder of 2017. Restricted Net Assets of Subsidiaries - As of September 30, 2017, the amount of IPL’s and WPL’s net assets 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 $1.7 billion and $1.8 billion, respectively. Comprehensive Income - For the three and nine months ended September 30, 2017 and 2016, 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 and nine months ended September 30, 2017 and 2016, 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, 2017 | 227,673,654 |
At-the-market offering program | 3,074,931 |
Shareowner Direct Plan issuances | 496,437 |
Equity-based compensation plans (Note 9(b)) | 5,185 |
Other | (45,847 | )
Shares outstanding, September 30, 2017 | 231,204,360 |
At-the-Market Offering Program - In May 2017, Alliant Energy filed a prospectus supplement under which it could sell up to $125 million of its common stock through an at-the-market offering program. As of September 30, 2017, Alliant Energy issued 3,074,931 shares of common stock through this program and received cash proceeds of $124 million, net of $1 million in commissions and fees. The proceeds from the issuances of common stock were used for general corporate purposes. Alliant Energy currently has no plans to issue any additional common stock through this at-the-market offering program. Dividend Restrictions - As of September 30, 2017, IPL’s amount of retained earnings that were free of dividend restrictions was $701 million. As of September 30, 2017, WPL’s amount of retained earnings that were free of dividend restrictions was $32 million for the remainder of 2017. Restricted Net Assets of Subsidiaries - As of September 30, 2017, the amount of IPL’s and WPL’s net assets 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 $1.7 billion and $1.8 billion, respectively. Comprehensive Income - For the three and nine months ended September 30, 2017 and 2016, 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 and nine months ended September 30, 2017 and 2016, 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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