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Common Equity | 3 Months Ended
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Mar. 31, 2018
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, 2018 | 231,348,646 |
Shareowner Direct Plan issuances | 166,527 |
Equity-based compensation plans (Note 10(b)) | 5,078 |
Other | (38,423 | )
Shares outstanding, March 31, 2018 | 231,481,828 |
Dividend Restrictions - As of March 31, 2018, IPL’s amount of retained earnings that were free of dividend restrictions was $683 million. As of March 31, 2018, WPL’s amount of retained earnings that were free of dividend restrictions was $105 million for the remainder of 2018. Restricted Net Assets of Subsidiaries - As of March 31, 2018, 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 $1.8 billion and $1.8 billion, respectively. Comprehensive Income - For the three months ended March 31, 2018 and 2017, 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, 2018 and 2017, 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, 2018 | 231,348,646 |
Shareowner Direct Plan issuances | 166,527 |
Equity-based compensation plans (Note 10(b)) | 5,078 |
Other | (38,423 | )
Shares outstanding, March 31, 2018 | 231,481,828 |
Dividend Restrictions - As of March 31, 2018, IPL’s amount of retained earnings that were free of dividend restrictions was $683 million. As of March 31, 2018, WPL’s amount of retained earnings that were free of dividend restrictions was $105 million for the remainder of 2018. Restricted Net Assets of Subsidiaries - As of March 31, 2018, 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 $1.8 billion and $1.8 billion, respectively. Comprehensive Income - For the three months ended March 31, 2018 and 2017, 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, 2018 and 2017, 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, 2018 | 231,348,646 |
Shareowner Direct Plan issuances | 166,527 |
Equity-based compensation plans (Note 10(b)) | 5,078 |
Other | (38,423 | )
Shares outstanding, March 31, 2018 | 231,481,828 |
Dividend Restrictions - As of March 31, 2018, IPL’s amount of retained earnings that were free of dividend restrictions was $683 million. As of March 31, 2018, WPL’s amount of retained earnings that were free of dividend restrictions was $105 million for the remainder of 2018. Restricted Net Assets of Subsidiaries - As of March 31, 2018, 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 $1.8 billion and $1.8 billion, respectively. Comprehensive Income - For the three months ended March 31, 2018 and 2017, 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, 2018 and 2017, 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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- Definition Common Equity [Line Items] + References No definition available. + Details
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- Definition The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -URI http://asc.fasb.org/topic&trid=2208762 + Details
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