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Common Equity | 9 Months Ended
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Sep. 30, 2015
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, 2015 | 110,935,680 |
At-the-market offering program | 2,186,617 |
Shareowner Direct Plan | 204,213 |
Equity-based compensation plans (Note 9(b)) | 56,378 |
Other | (22,463 | )
Shares outstanding, September 30, 2015 | 113,360,425 |
At-the-Market Offering Program - In March 2015, Alliant Energy filed a prospectus supplement under which it may sell up to $150 million of its common stock through an at-the-market offering program. As of September 30, 2015, Alliant Energy issued 2,186,617 shares of common stock through this program and received cash proceeds of $133 million, net of $2 million in fees and commissions. 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 the at-the-market offering program. Dividend Restrictions - As of September 30, 2015, IPL’s amount of retained earnings that were free of dividend restrictions was $615 million. As of September 30, 2015, WPL’s amount of retained earnings that were free of dividend restrictions was $32 million for the remainder of 2015. Restricted Net Assets of Subsidiaries - As of September 30, 2015, 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 $1.4 billion and $1.7 billion, respectively. Capital Transactions with Subsidiaries - For the nine months ended September 30, 2015, IPL received capital contributions of $100.0 million from its parent company. For the nine months ended September 30, 2015, IPL and WPL each paid common stock dividends of $105.0 million and $95.3 million, respectively, to its parent company. Comprehensive Income - For the three and nine months ended September 30, 2015 and 2014, 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, 2015 and 2014, 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, 2015 | 110,935,680 |
At-the-market offering program | 2,186,617 |
Shareowner Direct Plan | 204,213 |
Equity-based compensation plans (Note 9(b)) | 56,378 |
Other | (22,463 | )
Shares outstanding, September 30, 2015 | 113,360,425 |
At-the-Market Offering Program - In March 2015, Alliant Energy filed a prospectus supplement under which it may sell up to $150 million of its common stock through an at-the-market offering program. As of September 30, 2015, Alliant Energy issued 2,186,617 shares of common stock through this program and received cash proceeds of $133 million, net of $2 million in fees and commissions. 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 the at-the-market offering program. Dividend Restrictions - As of September 30, 2015, IPL’s amount of retained earnings that were free of dividend restrictions was $615 million. As of September 30, 2015, WPL’s amount of retained earnings that were free of dividend restrictions was $32 million for the remainder of 2015. Restricted Net Assets of Subsidiaries - As of September 30, 2015, 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 $1.4 billion and $1.7 billion, respectively. Capital Transactions with Subsidiaries - For the nine months ended September 30, 2015, IPL received capital contributions of $100.0 million from its parent company. For the nine months ended September 30, 2015, IPL and WPL each paid common stock dividends of $105.0 million and $95.3 million, respectively, to its parent company. Comprehensive Income - For the three and nine months ended September 30, 2015 and 2014, 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, 2015 and 2014, 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, 2015 | 110,935,680 |
At-the-market offering program | 2,186,617 |
Shareowner Direct Plan | 204,213 |
Equity-based compensation plans (Note 9(b)) | 56,378 |
Other | (22,463 | )
Shares outstanding, September 30, 2015 | 113,360,425 |
At-the-Market Offering Program - In March 2015, Alliant Energy filed a prospectus supplement under which it may sell up to $150 million of its common stock through an at-the-market offering program. As of September 30, 2015, Alliant Energy issued 2,186,617 shares of common stock through this program and received cash proceeds of $133 million, net of $2 million in fees and commissions. 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 the at-the-market offering program. Dividend Restrictions - As of September 30, 2015, IPL’s amount of retained earnings that were free of dividend restrictions was $615 million. As of September 30, 2015, WPL’s amount of retained earnings that were free of dividend restrictions was $32 million for the remainder of 2015. Restricted Net Assets of Subsidiaries - As of September 30, 2015, 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 $1.4 billion and $1.7 billion, respectively. Capital Transactions with Subsidiaries - For the nine months ended September 30, 2015, IPL received capital contributions of $100.0 million from its parent company. For the nine months ended September 30, 2015, IPL and WPL each paid common stock dividends of $105.0 million and $95.3 million, respectively, to its parent company. Comprehensive Income - For the three and nine months ended September 30, 2015 and 2014, 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, 2015 and 2014, 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 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 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(d),(e)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB TOPIC 4.E) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29-31) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB TOPIC 4.C) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Preferred Stock -URI http://asc.fasb.org/extlink&oid=6521494 Reference 12: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 13: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644 Reference 14: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph d -Article 4 Reference 15: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 Reference 16: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section E Reference 17: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Article 4 Reference 18: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section C Reference 19: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 + Details
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