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Common Equity (Tables) | 6 Months Ended
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Jun. 30, 2019
Schedule of Capitalization, Equity [Line Items] |
Common Share Activity | A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2019 | 236,063,279 |
Equity forward agreements | 1,090,300 |
Shareowner Direct Plan | 268,755 |
Equity-based compensation plans | 101,478 |
Other | (2,738 | )
Shares outstanding, June 30, 2019 | 237,521,074 |
Changes in Shareowners' Equity | A summary of changes in shareowners’ equity was as follows (in millions):
Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  | Cumulative |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  | Preferred |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Stock |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | of IPL |  | Equity
Three Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $2.4 |  |  |  | $2,100.0 |  |  |  | $2,587.3 |  |  |  | $2.4 |  |  |  | ($9.7 | ) |  |  | $200.0 |  |  |  | $4,882.4 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 94.6 |  |  |  |  |  |  |  |  | 94.6 |
Common stock dividends ($0.355 per share) |  |  |  |  | (84.1 | ) |  |  |  |  |  |  |  | (84.1 | )
Shareowner Direct Plan issuances |  |  |  | 6.0 |  |  |  |  |  |  |  |  |  |  | 6.0 |
Equity-based compensation plans and other |  |  | 2.4 |  |  |  |  |  |  | (0.3 | ) |  |  |  | 2.1 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1.4 | ) |  |  |  |  |  | (1.4 | )
Ending balance, June 30 |  | $2.4 |  |  |  | $2,108.4 |  |  |  | $2,597.8 |  |  |  | $1.0 |  |  |  | ($10.0 | ) |  |  | $200.0 |  |  |  | $4,899.6 |
Three Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $2.3 |  |  |  | $1,851.4 |  |  |  | $2,389.4 |  |  |  | ($0.5 | ) |  |  | ($11.1 | ) |  |  | $200.0 |  |  |  | $4,431.5 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 100.4 |  |  |  |  |  |  |  |  | 100.4 |
Common stock dividends ($0.335 per share) |  |  |  |  | (77.3 | ) |  |  |  |  |  |  |  | (77.3 | )
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 93.8 |  |  |  |  |  |  |  |  |  |  | 93.8 |
Equity-based compensation plans and other |  |  | 2.0 |  |  |  |  |  |  | (0.3 | ) |  |  |  | 1.7 |
Other comprehensive income, net of tax |  |  |  |  |  |  | 0.6 |  |  |  |  |  |  | 0.6 |
Ending balance, June 30 |  | $2.3 |  |  |  | $1,947.2 |  |  |  | $2,412.5 |  |  |  | $0.1 |  |  |  | ($11.4 | ) |  |  | $200.0 |  |  |  | $4,550.7 |
Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  | Cumulative |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  | Preferred |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Stock |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | of IPL |  | Equity
Six Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $2.4 |  |  |  | $2,045.5 |  |  |  | $2,545.9 |  |  |  | $1.7 |  |  |  | ($9.8 | ) |  |  | $200.0 |  |  |  | $4,785.7 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 219.7 |  |  |  |  |  |  |  |  | 219.7 |
Common stock dividends ($0.71 per share) |  |  |  |  | (167.8 | ) |  |  |  |  |  |  |  | (167.8 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 60.6 |  |  |  |  |  |  |  |  |  |  | 60.6 |
Equity-based compensation plans and other |  |  | 2.3 |  |  |  |  |  |  | (0.2 | ) |  |  |  | 2.1 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (0.7 | ) |  |  |  |  |  | (0.7 | )
Ending balance, June 30 |  | $2.4 |  |  |  | $2,108.4 |  |  |  | $2,597.8 |  |  |  | $1.0 |  |  |  | ($10.0 | ) |  |  | $200.0 |  |  |  | $4,899.6 |
Six Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $2.3 |  |  |  | $1,845.5 |  |  |  | $2,346.0 |  |  |  | ($0.5 | ) |  |  | ($11.1 | ) |  |  | $200.0 |  |  |  | $4,382.2 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 221.3 |  |  |  |  |  |  |  |  | 221.3 |
Common stock dividends ($0.67 per share) |  |  |  |  | (154.8 | ) |  |  |  |  |  |  |  | (154.8 | )
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 100.1 |  |  |  |  |  |  |  |  |  |  | 100.1 |
Equity-based compensation plans and other |  |  | 1.6 |  |  |  |  |  |  | (0.3 | ) |  |  |  | 1.3 |
Other comprehensive income, net of tax |  |  |  |  |  |  | 0.6 |  |  |  |  |  |  | 0.6 |
Ending balance, June 30 |  | $2.3 |  |  |  | $1,947.2 |  |  |  | $2,412.5 |  |  |  | $0.1 |  |  |  | ($11.4 | ) |  |  | $200.0 |  |  |  | $4,550.7 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $785.8 |  |  |  | $200.0 |  |  |  | $3,342.0 |
Earnings available for common stock |  |  |  |  | 45.0 |  |  |  |  | 45.0 |
Common stock dividends |  |  |  |  | (41.9 | ) |  |  |  | (41.9 | )
Ending balance, June 30 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $788.9 |  |  |  | $200.0 |  |  |  | $3,345.1 |
Three Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $33.4 |  |  |  | $1,797.8 |  |  |  | $683.3 |  |  |  | $200.0 |  |  |  | $2,714.5 |
Earnings available for common stock |  |  |  |  | 51.7 |  |  |  |  | 51.7 |
Common stock dividends |  |  |  |  | (42.1 | ) |  |  |  | (42.1 | )
Capital contributions from parent |  |  | 130.0 |  |  |  |  |  |  | 130.0 |
Ending balance, June 30 |  | $33.4 |  |  |  | $1,927.8 |  |  |  | $692.9 |  |  |  | $200.0 |  |  |  | $2,854.1 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Six Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $33.4 |  |  |  | $2,222.8 |  |  |  | $774.5 |  |  |  | $200.0 |  |  |  | $3,230.7 |
Earnings available for common stock |  |  |  |  | 98.3 |  |  |  |  | 98.3 |
Common stock dividends |  |  |  |  | (83.9 | ) |  |  |  | (83.9 | )
Capital contributions from parent |  |  | 100.0 |  |  |  |  |  |  | 100.0 |
Ending balance, June 30 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $788.9 |  |  |  | $200.0 |  |  |  | $3,345.1 |
Six Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $33.4 |  |  |  | $1,797.8 |  |  |  | $678.5 |  |  |  | $200.0 |  |  |  | $2,709.7 |
Earnings available for common stock |  |  |  |  | 98.4 |  |  |  |  | 98.4 |
Common stock dividends |  |  |  |  | (84.0 | ) |  |  |  | (84.0 | )
Capital contributions from parent |  |  | 130.0 |  |  |  |  |  |  | 130.0 |
Ending balance, June 30 |  | $33.4 |  |  |  | $1,927.8 |  |  |  | $692.9 |  |  |  | $200.0 |  |  |  | $2,854.1 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended June 30, 2019 |  |  |  |  |  |  |
Beginning balance, April 1 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $804.0 |  |  |  | $2,179.2 |
Earnings available for common stock |  |  |  |  | 42.0 |  |  | 42.0 |
Common stock dividends |  |  |  |  | (36.0 | ) |  | (36.0 | )
Ending balance, June 30 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $810.0 |  |  |  | $2,185.2 |
Three Months Ended June 30, 2018 |  |  |  |  |  |  |
Beginning balance, April 1 |  | $66.2 |  |  |  | $1,109.0 |  |  |  | $725.3 |  |  |  | $1,900.5 |
Earnings available for common stock |  |  |  |  | 39.8 |  |  | 39.8 |
Common stock dividends |  |  |  |  | (35.1 | ) |  | (35.1 | )
Capital contributions from parent |  |  | 150.0 |  |  |  |  | 150.0 |
Ending balance, June 30 |  | $66.2 |  |  |  | $1,259.0 |  |  |  | $730.0 |  |  |  | $2,055.2 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Six Months Ended June 30, 2019 |  |  |  |  |  |  |
Beginning balance, January 1 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $774.3 |  |  |  | $2,149.5 |
Earnings available for common stock |  |  |  |  | 107.7 |  |  | 107.7 |
Common stock dividends |  |  |  |  | (72.0 | ) |  | (72.0 | )
Ending balance, June 30 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $810.0 |  |  |  | $2,185.2 |
Six Months Ended June 30, 2018 |  |  |  |  |  |  |
Beginning balance, January 1 |  | $66.2 |  |  |  | $1,109.0 |  |  |  | $706.3 |  |  |  | $1,881.5 |
Earnings available for common stock |  |  |  |  | 93.8 |  |  | 93.8 |
Common stock dividends |  |  |  |  | (70.1 | ) |  | (70.1 | )
Capital contributions from parent |  |  | 150.0 |  |  |  |  | 150.0 |
Ending balance, June 30 |  | $66.2 |  |  |  | $1,259.0 |  |  |  | $730.0 |  |  |  | $2,055.2 |
IPL [Member] |
Schedule of Capitalization, Equity [Line Items] |
Changes in Shareowners' Equity | A summary of changes in shareowners’ equity was as follows (in millions):
Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  | Cumulative |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  | Preferred |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Stock |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | of IPL |  | Equity
Three Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $2.4 |  |  |  | $2,100.0 |  |  |  | $2,587.3 |  |  |  | $2.4 |  |  |  | ($9.7 | ) |  |  | $200.0 |  |  |  | $4,882.4 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 94.6 |  |  |  |  |  |  |  |  | 94.6 |
Common stock dividends ($0.355 per share) |  |  |  |  | (84.1 | ) |  |  |  |  |  |  |  | (84.1 | )
Shareowner Direct Plan issuances |  |  |  | 6.0 |  |  |  |  |  |  |  |  |  |  | 6.0 |
Equity-based compensation plans and other |  |  | 2.4 |  |  |  |  |  |  | (0.3 | ) |  |  |  | 2.1 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1.4 | ) |  |  |  |  |  | (1.4 | )
Ending balance, June 30 |  | $2.4 |  |  |  | $2,108.4 |  |  |  | $2,597.8 |  |  |  | $1.0 |  |  |  | ($10.0 | ) |  |  | $200.0 |  |  |  | $4,899.6 |
Three Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $2.3 |  |  |  | $1,851.4 |  |  |  | $2,389.4 |  |  |  | ($0.5 | ) |  |  | ($11.1 | ) |  |  | $200.0 |  |  |  | $4,431.5 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 100.4 |  |  |  |  |  |  |  |  | 100.4 |
Common stock dividends ($0.335 per share) |  |  |  |  | (77.3 | ) |  |  |  |  |  |  |  | (77.3 | )
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 93.8 |  |  |  |  |  |  |  |  |  |  | 93.8 |
Equity-based compensation plans and other |  |  | 2.0 |  |  |  |  |  |  | (0.3 | ) |  |  |  | 1.7 |
Other comprehensive income, net of tax |  |  |  |  |  |  | 0.6 |  |  |  |  |  |  | 0.6 |
Ending balance, June 30 |  | $2.3 |  |  |  | $1,947.2 |  |  |  | $2,412.5 |  |  |  | $0.1 |  |  |  | ($11.4 | ) |  |  | $200.0 |  |  |  | $4,550.7 |
Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  | Cumulative |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  | Preferred |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Stock |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | of IPL |  | Equity
Six Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $2.4 |  |  |  | $2,045.5 |  |  |  | $2,545.9 |  |  |  | $1.7 |  |  |  | ($9.8 | ) |  |  | $200.0 |  |  |  | $4,785.7 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 219.7 |  |  |  |  |  |  |  |  | 219.7 |
Common stock dividends ($0.71 per share) |  |  |  |  | (167.8 | ) |  |  |  |  |  |  |  | (167.8 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 60.6 |  |  |  |  |  |  |  |  |  |  | 60.6 |
Equity-based compensation plans and other |  |  | 2.3 |  |  |  |  |  |  | (0.2 | ) |  |  |  | 2.1 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (0.7 | ) |  |  |  |  |  | (0.7 | )
Ending balance, June 30 |  | $2.4 |  |  |  | $2,108.4 |  |  |  | $2,597.8 |  |  |  | $1.0 |  |  |  | ($10.0 | ) |  |  | $200.0 |  |  |  | $4,899.6 |
Six Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $2.3 |  |  |  | $1,845.5 |  |  |  | $2,346.0 |  |  |  | ($0.5 | ) |  |  | ($11.1 | ) |  |  | $200.0 |  |  |  | $4,382.2 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 221.3 |  |  |  |  |  |  |  |  | 221.3 |
Common stock dividends ($0.67 per share) |  |  |  |  | (154.8 | ) |  |  |  |  |  |  |  | (154.8 | )
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 100.1 |  |  |  |  |  |  |  |  |  |  | 100.1 |
Equity-based compensation plans and other |  |  | 1.6 |  |  |  |  |  |  | (0.3 | ) |  |  |  | 1.3 |
Other comprehensive income, net of tax |  |  |  |  |  |  | 0.6 |  |  |  |  |  |  | 0.6 |
Ending balance, June 30 |  | $2.3 |  |  |  | $1,947.2 |  |  |  | $2,412.5 |  |  |  | $0.1 |  |  |  | ($11.4 | ) |  |  | $200.0 |  |  |  | $4,550.7 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $785.8 |  |  |  | $200.0 |  |  |  | $3,342.0 |
Earnings available for common stock |  |  |  |  | 45.0 |  |  |  |  | 45.0 |
Common stock dividends |  |  |  |  | (41.9 | ) |  |  |  | (41.9 | )
Ending balance, June 30 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $788.9 |  |  |  | $200.0 |  |  |  | $3,345.1 |
Three Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $33.4 |  |  |  | $1,797.8 |  |  |  | $683.3 |  |  |  | $200.0 |  |  |  | $2,714.5 |
Earnings available for common stock |  |  |  |  | 51.7 |  |  |  |  | 51.7 |
Common stock dividends |  |  |  |  | (42.1 | ) |  |  |  | (42.1 | )
Capital contributions from parent |  |  | 130.0 |  |  |  |  |  |  | 130.0 |
Ending balance, June 30 |  | $33.4 |  |  |  | $1,927.8 |  |  |  | $692.9 |  |  |  | $200.0 |  |  |  | $2,854.1 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Six Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $33.4 |  |  |  | $2,222.8 |  |  |  | $774.5 |  |  |  | $200.0 |  |  |  | $3,230.7 |
Earnings available for common stock |  |  |  |  | 98.3 |  |  |  |  | 98.3 |
Common stock dividends |  |  |  |  | (83.9 | ) |  |  |  | (83.9 | )
Capital contributions from parent |  |  | 100.0 |  |  |  |  |  |  | 100.0 |
Ending balance, June 30 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $788.9 |  |  |  | $200.0 |  |  |  | $3,345.1 |
Six Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $33.4 |  |  |  | $1,797.8 |  |  |  | $678.5 |  |  |  | $200.0 |  |  |  | $2,709.7 |
Earnings available for common stock |  |  |  |  | 98.4 |  |  |  |  | 98.4 |
Common stock dividends |  |  |  |  | (84.0 | ) |  |  |  | (84.0 | )
Capital contributions from parent |  |  | 130.0 |  |  |  |  |  |  | 130.0 |
Ending balance, June 30 |  | $33.4 |  |  |  | $1,927.8 |  |  |  | $692.9 |  |  |  | $200.0 |  |  |  | $2,854.1 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended June 30, 2019 |  |  |  |  |  |  |
Beginning balance, April 1 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $804.0 |  |  |  | $2,179.2 |
Earnings available for common stock |  |  |  |  | 42.0 |  |  | 42.0 |
Common stock dividends |  |  |  |  | (36.0 | ) |  | (36.0 | )
Ending balance, June 30 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $810.0 |  |  |  | $2,185.2 |
Three Months Ended June 30, 2018 |  |  |  |  |  |  |
Beginning balance, April 1 |  | $66.2 |  |  |  | $1,109.0 |  |  |  | $725.3 |  |  |  | $1,900.5 |
Earnings available for common stock |  |  |  |  | 39.8 |  |  | 39.8 |
Common stock dividends |  |  |  |  | (35.1 | ) |  | (35.1 | )
Capital contributions from parent |  |  | 150.0 |  |  |  |  | 150.0 |
Ending balance, June 30 |  | $66.2 |  |  |  | $1,259.0 |  |  |  | $730.0 |  |  |  | $2,055.2 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Six Months Ended June 30, 2019 |  |  |  |  |  |  |
Beginning balance, January 1 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $774.3 |  |  |  | $2,149.5 |
Earnings available for common stock |  |  |  |  | 107.7 |  |  | 107.7 |
Common stock dividends |  |  |  |  | (72.0 | ) |  | (72.0 | )
Ending balance, June 30 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $810.0 |  |  |  | $2,185.2 |
Six Months Ended June 30, 2018 |  |  |  |  |  |  |
Beginning balance, January 1 |  | $66.2 |  |  |  | $1,109.0 |  |  |  | $706.3 |  |  |  | $1,881.5 |
Earnings available for common stock |  |  |  |  | 93.8 |  |  | 93.8 |
Common stock dividends |  |  |  |  | (70.1 | ) |  | (70.1 | )
Capital contributions from parent |  |  | 150.0 |  |  |  |  | 150.0 |
Ending balance, June 30 |  | $66.2 |  |  |  | $1,259.0 |  |  |  | $730.0 |  |  |  | $2,055.2 |
WPL [Member] |
Schedule of Capitalization, Equity [Line Items] |
Changes in Shareowners' Equity | A summary of changes in shareowners’ equity was as follows (in millions):
Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  | Cumulative |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  | Preferred |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Stock |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | of IPL |  | Equity
Three Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $2.4 |  |  |  | $2,100.0 |  |  |  | $2,587.3 |  |  |  | $2.4 |  |  |  | ($9.7 | ) |  |  | $200.0 |  |  |  | $4,882.4 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 94.6 |  |  |  |  |  |  |  |  | 94.6 |
Common stock dividends ($0.355 per share) |  |  |  |  | (84.1 | ) |  |  |  |  |  |  |  | (84.1 | )
Shareowner Direct Plan issuances |  |  |  | 6.0 |  |  |  |  |  |  |  |  |  |  | 6.0 |
Equity-based compensation plans and other |  |  | 2.4 |  |  |  |  |  |  | (0.3 | ) |  |  |  | 2.1 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1.4 | ) |  |  |  |  |  | (1.4 | )
Ending balance, June 30 |  | $2.4 |  |  |  | $2,108.4 |  |  |  | $2,597.8 |  |  |  | $1.0 |  |  |  | ($10.0 | ) |  |  | $200.0 |  |  |  | $4,899.6 |
Three Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $2.3 |  |  |  | $1,851.4 |  |  |  | $2,389.4 |  |  |  | ($0.5 | ) |  |  | ($11.1 | ) |  |  | $200.0 |  |  |  | $4,431.5 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 100.4 |  |  |  |  |  |  |  |  | 100.4 |
Common stock dividends ($0.335 per share) |  |  |  |  | (77.3 | ) |  |  |  |  |  |  |  | (77.3 | )
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 93.8 |  |  |  |  |  |  |  |  |  |  | 93.8 |
Equity-based compensation plans and other |  |  | 2.0 |  |  |  |  |  |  | (0.3 | ) |  |  |  | 1.7 |
Other comprehensive income, net of tax |  |  |  |  |  |  | 0.6 |  |  |  |  |  |  | 0.6 |
Ending balance, June 30 |  | $2.3 |  |  |  | $1,947.2 |  |  |  | $2,412.5 |  |  |  | $0.1 |  |  |  | ($11.4 | ) |  |  | $200.0 |  |  |  | $4,550.7 |
Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  | Cumulative |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  | Preferred |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Stock |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | of IPL |  | Equity
Six Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $2.4 |  |  |  | $2,045.5 |  |  |  | $2,545.9 |  |  |  | $1.7 |  |  |  | ($9.8 | ) |  |  | $200.0 |  |  |  | $4,785.7 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 219.7 |  |  |  |  |  |  |  |  | 219.7 |
Common stock dividends ($0.71 per share) |  |  |  |  | (167.8 | ) |  |  |  |  |  |  |  | (167.8 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 60.6 |  |  |  |  |  |  |  |  |  |  | 60.6 |
Equity-based compensation plans and other |  |  | 2.3 |  |  |  |  |  |  | (0.2 | ) |  |  |  | 2.1 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (0.7 | ) |  |  |  |  |  | (0.7 | )
Ending balance, June 30 |  | $2.4 |  |  |  | $2,108.4 |  |  |  | $2,597.8 |  |  |  | $1.0 |  |  |  | ($10.0 | ) |  |  | $200.0 |  |  |  | $4,899.6 |
Six Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $2.3 |  |  |  | $1,845.5 |  |  |  | $2,346.0 |  |  |  | ($0.5 | ) |  |  | ($11.1 | ) |  |  | $200.0 |  |  |  | $4,382.2 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 221.3 |  |  |  |  |  |  |  |  | 221.3 |
Common stock dividends ($0.67 per share) |  |  |  |  | (154.8 | ) |  |  |  |  |  |  |  | (154.8 | )
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 100.1 |  |  |  |  |  |  |  |  |  |  | 100.1 |
Equity-based compensation plans and other |  |  | 1.6 |  |  |  |  |  |  | (0.3 | ) |  |  |  | 1.3 |
Other comprehensive income, net of tax |  |  |  |  |  |  | 0.6 |  |  |  |  |  |  | 0.6 |
Ending balance, June 30 |  | $2.3 |  |  |  | $1,947.2 |  |  |  | $2,412.5 |  |  |  | $0.1 |  |  |  | ($11.4 | ) |  |  | $200.0 |  |  |  | $4,550.7 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $785.8 |  |  |  | $200.0 |  |  |  | $3,342.0 |
Earnings available for common stock |  |  |  |  | 45.0 |  |  |  |  | 45.0 |
Common stock dividends |  |  |  |  | (41.9 | ) |  |  |  | (41.9 | )
Ending balance, June 30 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $788.9 |  |  |  | $200.0 |  |  |  | $3,345.1 |
Three Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |
Beginning balance, April 1 |  | $33.4 |  |  |  | $1,797.8 |  |  |  | $683.3 |  |  |  | $200.0 |  |  |  | $2,714.5 |
Earnings available for common stock |  |  |  |  | 51.7 |  |  |  |  | 51.7 |
Common stock dividends |  |  |  |  | (42.1 | ) |  |  |  | (42.1 | )
Capital contributions from parent |  |  | 130.0 |  |  |  |  |  |  | 130.0 |
Ending balance, June 30 |  | $33.4 |  |  |  | $1,927.8 |  |  |  | $692.9 |  |  |  | $200.0 |  |  |  | $2,854.1 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Six Months Ended June 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $33.4 |  |  |  | $2,222.8 |  |  |  | $774.5 |  |  |  | $200.0 |  |  |  | $3,230.7 |
Earnings available for common stock |  |  |  |  | 98.3 |  |  |  |  | 98.3 |
Common stock dividends |  |  |  |  | (83.9 | ) |  |  |  | (83.9 | )
Capital contributions from parent |  |  | 100.0 |  |  |  |  |  |  | 100.0 |
Ending balance, June 30 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $788.9 |  |  |  | $200.0 |  |  |  | $3,345.1 |
Six Months Ended June 30, 2018 |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $33.4 |  |  |  | $1,797.8 |  |  |  | $678.5 |  |  |  | $200.0 |  |  |  | $2,709.7 |
Earnings available for common stock |  |  |  |  | 98.4 |  |  |  |  | 98.4 |
Common stock dividends |  |  |  |  | (84.0 | ) |  |  |  | (84.0 | )
Capital contributions from parent |  |  | 130.0 |  |  |  |  |  |  | 130.0 |
Ending balance, June 30 |  | $33.4 |  |  |  | $1,927.8 |  |  |  | $692.9 |  |  |  | $200.0 |  |  |  | $2,854.1 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended June 30, 2019 |  |  |  |  |  |  |
Beginning balance, April 1 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $804.0 |  |  |  | $2,179.2 |
Earnings available for common stock |  |  |  |  | 42.0 |  |  | 42.0 |
Common stock dividends |  |  |  |  | (36.0 | ) |  | (36.0 | )
Ending balance, June 30 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $810.0 |  |  |  | $2,185.2 |
Three Months Ended June 30, 2018 |  |  |  |  |  |  |
Beginning balance, April 1 |  | $66.2 |  |  |  | $1,109.0 |  |  |  | $725.3 |  |  |  | $1,900.5 |
Earnings available for common stock |  |  |  |  | 39.8 |  |  | 39.8 |
Common stock dividends |  |  |  |  | (35.1 | ) |  | (35.1 | )
Capital contributions from parent |  |  | 150.0 |  |  |  |  | 150.0 |
Ending balance, June 30 |  | $66.2 |  |  |  | $1,259.0 |  |  |  | $730.0 |  |  |  | $2,055.2 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Six Months Ended June 30, 2019 |  |  |  |  |  |  |
Beginning balance, January 1 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $774.3 |  |  |  | $2,149.5 |
Earnings available for common stock |  |  |  |  | 107.7 |  |  | 107.7 |
Common stock dividends |  |  |  |  | (72.0 | ) |  | (72.0 | )
Ending balance, June 30 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $810.0 |  |  |  | $2,185.2 |
Six Months Ended June 30, 2018 |  |  |  |  |  |  |
Beginning balance, January 1 |  | $66.2 |  |  |  | $1,109.0 |  |  |  | $706.3 |  |  |  | $1,881.5 |
Earnings available for common stock |  |  |  |  | 93.8 |  |  | 93.8 |
Common stock dividends |  |  |  |  | (70.1 | ) |  | (70.1 | )
Capital contributions from parent |  |  | 150.0 |  |  |  |  | 150.0 |
Ending balance, June 30 |  | $66.2 |  |  |  | $1,259.0 |  |  |  | $730.0 |  |  |  | $2,055.2 |

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