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Common Equity | 12 Months Ended
--- | ---
Dec. 31, 2015
Schedule of Common Equity [Line Items] |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
| 2015 |  | 2014 |  | 2013
Shares outstanding, January 1 | 110,935,680 |  |  | 110,943,669 |  |  | 110,987,400 |
At-the-market offering program | 2,186,617 |  |  | — |  |  | — |
Shareowner Direct Plan issuances | 303,005 |  |  | — |  |  | — |
Equity-based compensation plans (Note 12(b)) | 56,378 |  |  | 35,547 |  |  | (23,374 | )
Other | (22,464 | ) |  | (43,536 | ) |  | (20,357 | )
Shares outstanding, December 31 | 113,459,216 |  |  | 110,935,680 |  |  | 110,943,669 |
At December 31, 2015, Alliant Energy had a total of 7.3 million shares available for issuance in the aggregate, pursuant to its Amended and Restated OIP, Shareowner Direct Plan and 401(k) Savings Plan. 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 December 31, 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. Shareowner Direct Plan - Beginning in 2015, Alliant Energy satisfied its requirements under the Shareowner Direct Plan (dividend reinvestment and stock purchase plan) by acquiring Alliant Energy common stock through original issue, rather than on the open market. Shareowner Rights Agreement - Alliant Energy has established an amended and restated Shareowner Rights Agreement. The rights under this agreement will only become exercisable if a person or group has acquired, or announced an intention to acquire, 15% or more of Alliant Energy’s outstanding common stock. Each right will initially entitle registered shareowners to purchase from Alliant Energy one-half of one share of Alliant Energy’s common stock. The rights will be exercisable at an initial price of $110.00 per full share, subject to adjustment. If any shareowner acquires 15% or more of the outstanding common stock of Alliant Energy, each right (subject to limitations) will entitle its holder to purchase, at the right’s then current exercise price, a number of common shares of Alliant Energy or of the acquirer having a market value at the time of twice the right’s per full share exercise price. Alliant Energy’s Board of Directors is authorized to reduce the 15% ownership threshold to not less than 10%. The amended and restated Shareowner Rights Agreement expires in December 2018. Dividend Restrictions - Alliant Energy does not have any significant common stock dividend restrictions. IPL and WPL each have common stock dividend restrictions based on applicable regulatory limitations. IPL also has common stock dividend restrictions based on the terms of its outstanding preferred stock. As of December 31, 2015, IPL and WPL were in compliance with all such dividend restrictions. IPL is restricted from paying common stock dividends to its parent company, Alliant Energy, if for any past or current dividend period, dividends on its preferred stock have not been paid, or declared and set apart for payment. IPL has paid all dividends on its preferred stock through 2015. Under the Federal Power Act, IPL may not pay dividends to its parent company in excess of the current amount of its retained earnings. As of December 31, 2015, IPL’s amount of retained earnings that were free of dividend restrictions was $554 million. If IPL’s actual 13-month average common equity ratio (calculated on a financial basis consistent with IPL’s rate cases) falls below 42% of total capitalization, IPL is required to notify the IUB. Currently, WPL has a regulatory limitation on distributions to its parent company from an order issued by the PSCW in July 2014. The order prohibits WPL from paying annual common stock dividends to its parent company in excess of $135 million in 2016 if WPL’s actual 13-month average common equity ratio (calculated on a financial basis consistent with WPL’s rate cases) would fall below 52.25% for 2016. As of December 31, 2015, WPL’s amount of retained earnings that were free of dividend restrictions was $135 million for 2016. Restricted Net Assets of Subsidiaries - IPL and WPL do not have regulatory authority to lend or advance any amounts to their parent company. As of December 31, 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 as follows (in billions):
| 2015 |  | 2014
IPL |  | $1.4 |  |  |  | $1.3 |
WPL | 1.6 |  |  | 1.6 |
Capital Transactions With Subsidiaries - IPL, WPL and Resources paid common stock dividends and repayments of capital to their parent company, Alliant Energy, as follows (in millions):
| IPL |  | WPL |  | Resources
| 2015 |  | 2014 |  | 2013 |  | 2015 |  | 2014 |  | 2013 |  | 2015 |  | 2014 |  | 2013
Common stock dividends |  | $140.0 |  |  |  | $140.0 |  |  |  | $128.1 |  |  |  | $126.9 |  |  |  | $118.7 |  |  |  | $116.3 |  |  |  | $— |  |  |  | $— |  |  |  | $— |
Repayments of capital | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 50.0 |  |  | 95.0 |
Total distributions from common equity |  | $140.0 |  |  |  | $140.0 |  |  |  | $128.1 |  |  |  | $126.9 |  |  |  | $118.7 |  |  |  | $116.3 |  |  |  | $— |  |  |  | $50.0 |  |  |  | $95.0 |
IPL received capital contributions from its parent company, Alliant Energy, as follows (in millions):
2015 |  | 2014 |  | 2013
| $165.0 |  |  |  | $90.0 |  |  |  | $120.0 |
Comprehensive Income - In 2015, 2014 and 2013, Alliant Energy’s other comprehensive income (loss) was $0.2 million, ($0.4) million and $0.6 million, respectively; therefore, its comprehensive income was substantially equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was substantially equal to its net income attributable to Alliant Energy common shareowners for such periods. In 2015, 2014 and 2013, 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] |
Schedule of Common Equity [Line Items] |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
| 2015 |  | 2014 |  | 2013
Shares outstanding, January 1 | 110,935,680 |  |  | 110,943,669 |  |  | 110,987,400 |
At-the-market offering program | 2,186,617 |  |  | — |  |  | — |
Shareowner Direct Plan issuances | 303,005 |  |  | — |  |  | — |
Equity-based compensation plans (Note 12(b)) | 56,378 |  |  | 35,547 |  |  | (23,374 | )
Other | (22,464 | ) |  | (43,536 | ) |  | (20,357 | )
Shares outstanding, December 31 | 113,459,216 |  |  | 110,935,680 |  |  | 110,943,669 |
At December 31, 2015, Alliant Energy had a total of 7.3 million shares available for issuance in the aggregate, pursuant to its Amended and Restated OIP, Shareowner Direct Plan and 401(k) Savings Plan. 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 December 31, 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. Shareowner Direct Plan - Beginning in 2015, Alliant Energy satisfied its requirements under the Shareowner Direct Plan (dividend reinvestment and stock purchase plan) by acquiring Alliant Energy common stock through original issue, rather than on the open market. Shareowner Rights Agreement - Alliant Energy has established an amended and restated Shareowner Rights Agreement. The rights under this agreement will only become exercisable if a person or group has acquired, or announced an intention to acquire, 15% or more of Alliant Energy’s outstanding common stock. Each right will initially entitle registered shareowners to purchase from Alliant Energy one-half of one share of Alliant Energy’s common stock. The rights will be exercisable at an initial price of $110.00 per full share, subject to adjustment. If any shareowner acquires 15% or more of the outstanding common stock of Alliant Energy, each right (subject to limitations) will entitle its holder to purchase, at the right’s then current exercise price, a number of common shares of Alliant Energy or of the acquirer having a market value at the time of twice the right’s per full share exercise price. Alliant Energy’s Board of Directors is authorized to reduce the 15% ownership threshold to not less than 10%. The amended and restated Shareowner Rights Agreement expires in December 2018. Dividend Restrictions - Alliant Energy does not have any significant common stock dividend restrictions. IPL and WPL each have common stock dividend restrictions based on applicable regulatory limitations. IPL also has common stock dividend restrictions based on the terms of its outstanding preferred stock. As of December 31, 2015, IPL and WPL were in compliance with all such dividend restrictions. IPL is restricted from paying common stock dividends to its parent company, Alliant Energy, if for any past or current dividend period, dividends on its preferred stock have not been paid, or declared and set apart for payment. IPL has paid all dividends on its preferred stock through 2015. Under the Federal Power Act, IPL may not pay dividends to its parent company in excess of the current amount of its retained earnings. As of December 31, 2015, IPL’s amount of retained earnings that were free of dividend restrictions was $554 million. If IPL’s actual 13-month average common equity ratio (calculated on a financial basis consistent with IPL’s rate cases) falls below 42% of total capitalization, IPL is required to notify the IUB. Currently, WPL has a regulatory limitation on distributions to its parent company from an order issued by the PSCW in July 2014. The order prohibits WPL from paying annual common stock dividends to its parent company in excess of $135 million in 2016 if WPL’s actual 13-month average common equity ratio (calculated on a financial basis consistent with WPL’s rate cases) would fall below 52.25% for 2016. As of December 31, 2015, WPL’s amount of retained earnings that were free of dividend restrictions was $135 million for 2016. Restricted Net Assets of Subsidiaries - IPL and WPL do not have regulatory authority to lend or advance any amounts to their parent company. As of December 31, 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 as follows (in billions):
| 2015 |  | 2014
IPL |  | $1.4 |  |  |  | $1.3 |
WPL | 1.6 |  |  | 1.6 |
Capital Transactions With Subsidiaries - IPL, WPL and Resources paid common stock dividends and repayments of capital to their parent company, Alliant Energy, as follows (in millions):
| IPL |  | WPL |  | Resources
| 2015 |  | 2014 |  | 2013 |  | 2015 |  | 2014 |  | 2013 |  | 2015 |  | 2014 |  | 2013
Common stock dividends |  | $140.0 |  |  |  | $140.0 |  |  |  | $128.1 |  |  |  | $126.9 |  |  |  | $118.7 |  |  |  | $116.3 |  |  |  | $— |  |  |  | $— |  |  |  | $— |
Repayments of capital | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 50.0 |  |  | 95.0 |
Total distributions from common equity |  | $140.0 |  |  |  | $140.0 |  |  |  | $128.1 |  |  |  | $126.9 |  |  |  | $118.7 |  |  |  | $116.3 |  |  |  | $— |  |  |  | $50.0 |  |  |  | $95.0 |
IPL received capital contributions from its parent company, Alliant Energy, as follows (in millions):
2015 |  | 2014 |  | 2013
| $165.0 |  |  |  | $90.0 |  |  |  | $120.0 |
Comprehensive Income - In 2015, 2014 and 2013, Alliant Energy’s other comprehensive income (loss) was $0.2 million, ($0.4) million and $0.6 million, respectively; therefore, its comprehensive income was substantially equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was substantially equal to its net income attributable to Alliant Energy common shareowners for such periods. In 2015, 2014 and 2013, 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] |
Schedule of Common Equity [Line Items] |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
| 2015 |  | 2014 |  | 2013
Shares outstanding, January 1 | 110,935,680 |  |  | 110,943,669 |  |  | 110,987,400 |
At-the-market offering program | 2,186,617 |  |  | — |  |  | — |
Shareowner Direct Plan issuances | 303,005 |  |  | — |  |  | — |
Equity-based compensation plans (Note 12(b)) | 56,378 |  |  | 35,547 |  |  | (23,374 | )
Other | (22,464 | ) |  | (43,536 | ) |  | (20,357 | )
Shares outstanding, December 31 | 113,459,216 |  |  | 110,935,680 |  |  | 110,943,669 |
At December 31, 2015, Alliant Energy had a total of 7.3 million shares available for issuance in the aggregate, pursuant to its Amended and Restated OIP, Shareowner Direct Plan and 401(k) Savings Plan. 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 December 31, 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. Shareowner Direct Plan - Beginning in 2015, Alliant Energy satisfied its requirements under the Shareowner Direct Plan (dividend reinvestment and stock purchase plan) by acquiring Alliant Energy common stock through original issue, rather than on the open market. Shareowner Rights Agreement - Alliant Energy has established an amended and restated Shareowner Rights Agreement. The rights under this agreement will only become exercisable if a person or group has acquired, or announced an intention to acquire, 15% or more of Alliant Energy’s outstanding common stock. Each right will initially entitle registered shareowners to purchase from Alliant Energy one-half of one share of Alliant Energy’s common stock. The rights will be exercisable at an initial price of $110.00 per full share, subject to adjustment. If any shareowner acquires 15% or more of the outstanding common stock of Alliant Energy, each right (subject to limitations) will entitle its holder to purchase, at the right’s then current exercise price, a number of common shares of Alliant Energy or of the acquirer having a market value at the time of twice the right’s per full share exercise price. Alliant Energy’s Board of Directors is authorized to reduce the 15% ownership threshold to not less than 10%. The amended and restated Shareowner Rights Agreement expires in December 2018. Dividend Restrictions - Alliant Energy does not have any significant common stock dividend restrictions. IPL and WPL each have common stock dividend restrictions based on applicable regulatory limitations. IPL also has common stock dividend restrictions based on the terms of its outstanding preferred stock. As of December 31, 2015, IPL and WPL were in compliance with all such dividend restrictions. IPL is restricted from paying common stock dividends to its parent company, Alliant Energy, if for any past or current dividend period, dividends on its preferred stock have not been paid, or declared and set apart for payment. IPL has paid all dividends on its preferred stock through 2015. Under the Federal Power Act, IPL may not pay dividends to its parent company in excess of the current amount of its retained earnings. As of December 31, 2015, IPL’s amount of retained earnings that were free of dividend restrictions was $554 million. If IPL’s actual 13-month average common equity ratio (calculated on a financial basis consistent with IPL’s rate cases) falls below 42% of total capitalization, IPL is required to notify the IUB. Currently, WPL has a regulatory limitation on distributions to its parent company from an order issued by the PSCW in July 2014. The order prohibits WPL from paying annual common stock dividends to its parent company in excess of $135 million in 2016 if WPL’s actual 13-month average common equity ratio (calculated on a financial basis consistent with WPL’s rate cases) would fall below 52.25% for 2016. As of December 31, 2015, WPL’s amount of retained earnings that were free of dividend restrictions was $135 million for 2016. Restricted Net Assets of Subsidiaries - IPL and WPL do not have regulatory authority to lend or advance any amounts to their parent company. As of December 31, 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 as follows (in billions):
| 2015 |  | 2014
IPL |  | $1.4 |  |  |  | $1.3 |
WPL | 1.6 |  |  | 1.6 |
Capital Transactions With Subsidiaries - IPL, WPL and Resources paid common stock dividends and repayments of capital to their parent company, Alliant Energy, as follows (in millions):
| IPL |  | WPL |  | Resources
| 2015 |  | 2014 |  | 2013 |  | 2015 |  | 2014 |  | 2013 |  | 2015 |  | 2014 |  | 2013
Common stock dividends |  | $140.0 |  |  |  | $140.0 |  |  |  | $128.1 |  |  |  | $126.9 |  |  |  | $118.7 |  |  |  | $116.3 |  |  |  | $— |  |  |  | $— |  |  |  | $— |
Repayments of capital | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 50.0 |  |  | 95.0 |
Total distributions from common equity |  | $140.0 |  |  |  | $140.0 |  |  |  | $128.1 |  |  |  | $126.9 |  |  |  | $118.7 |  |  |  | $116.3 |  |  |  | $— |  |  |  | $50.0 |  |  |  | $95.0 |
IPL received capital contributions from its parent company, Alliant Energy, as follows (in millions):
2015 |  | 2014 |  | 2013
| $165.0 |  |  |  | $90.0 |  |  |  | $120.0 |
Comprehensive Income - In 2015, 2014 and 2013, Alliant Energy’s other comprehensive income (loss) was $0.2 million, ($0.4) million and $0.6 million, respectively; therefore, its comprehensive income was substantially equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was substantially equal to its net income attributable to Alliant Energy common shareowners for such periods. In 2015, 2014 and 2013, 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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