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Common Equity (Tables) | 9 Months Ended
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Sep. 30, 2020
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, 2020 | 245,022,800 |
Equity forward agreements | 4,275,127 |
Shareowner Direct Plan | 364,531 |
Equity-based compensation plans | 98,205 |
Shares outstanding, September 30, 2020 | 249,760,663 |
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 September 30, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2020 |  | $2 |  |  |  | $2,683 |  |  |  | $2,874 |  |  |  | ($1 | ) |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,748 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 246 |  |  |  |  |  |  |  |  | 246 |
Common stock dividends ($0.38 per share) |  |  |  |  | (94 | ) |  |  |  |  |  |  |  | (94 | )
Shareowner Direct Plan issuances |  |  |  | 6 |  |  |  |  |  |  |  |  |  |  | 6 |
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  |  | (1 | ) |  |  |  | 3 |
Ending balance, September 30, 2020 |  | $2 |  |  |  | $2,693 |  |  |  | $3,026 |  |  |  | ($1 | ) |  |  | ($11 | ) |  |  | $200 |  |  |  | $5,909 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2019 |  | $2 |  |  |  | $2,109 |  |  |  | $2,598 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $4,900 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 226 |  |  |  |  |  |  |  |  | 226 |
Common stock dividends ($0.355 per share) |  |  |  |  | (85 | ) |  |  |  |  |  |  |  | (85 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 125 |  |  |  |  |  |  |  |  |  |  | 125 |
Equity-based compensation plans and other |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  | 3 |
Ending balance, September 30, 2019 |  | $2 |  |  |  | $2,237 |  |  |  | $2,739 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,169 |
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
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 |  | $2 |  |  |  | $2,446 |  |  |  | $2,766 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,405 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 550 |  |  |  |  |  |  |  |  | 550 |
Common stock dividends ($1.14 per share) |  |  |  |  | (281 | ) |  |  |  |  |  |  |  | (281 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 241 |  |  |  |  |  |  |  |  |  |  | 241 |
Equity-based compensation plans and other |  |  | 6 |  |  |  |  |  |  | (1 | ) |  |  |  | 5 |
Adoption of new accounting standard, net of tax (refer to Note 1(d)) |  |  |  |  | (9 | ) |  |  |  |  |  |  |  | (9 | )
Other comprehensive loss, net of tax |  |  |  |  |  |  | (2 | ) |  |  |  |  |  | (2 | )
Ending balance, September 30, 2020 |  | $2 |  |  |  | $2,693 |  |  |  | $3,026 |  |  |  | ($1 | ) |  |  | ($11 | ) |  |  | $200 |  |  |  | $5,909 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2018 |  | $2 |  |  |  | $2,046 |  |  |  | $2,546 |  |  |  | $2 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $4,786 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 446 |  |  |  |  |  |  |  |  | 446 |
Common stock dividends ($1.065 per share) |  |  |  |  | (253 | ) |  |  |  |  |  |  |  | (253 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  | 185 |  |  |  |  |  |  |  |  |  |  | 185 |
Equity-based compensation plans and other |  |  | 6 |  |  |  |  |  |  |  |  |  |  |  | 6 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1 | ) |  |  |  |  |  | (1 | )
Ending balance, September 30, 2019 |  | $2 |  |  |  | $2,237 |  |  |  | $2,739 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,169 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2020 |  | $33 |  |  |  | $2,523 |  |  |  | $915 |  |  |  | $200 |  |  |  | $3,671 |
Net income available for common stock |  |  |  |  | 148 |  |  |  |  | 148 |
Common stock dividends |  |  |  |  | (59 | ) |  |  |  | (59 | )
Capital contributions from parent |  |  | 170 |  |  |  |  |  |  | 170 |
Ending balance, September 30, 2020 |  | $33 |  |  |  | $2,693 |  |  |  | $1,004 |  |  |  | $200 |  |  |  | $3,930 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2019 |  | $33 |  |  |  | $2,323 |  |  |  | $789 |  |  |  | $200 |  |  |  | $3,345 |
Net income available for common stock |  |  |  |  | 141 |  |  |  |  | 141 |
Common stock dividends |  |  |  |  | (42 | ) |  |  |  | (42 | )
Ending balance, September 30, 2019 |  | $33 |  |  |  | $2,323 |  |  |  | $888 |  |  |  | $200 |  |  |  | $3,444 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 |  | $33 |  |  |  | $2,348 |  |  |  | $891 |  |  |  | $200 |  |  |  | $3,472 |
Net income available for common stock |  |  |  |  | 290 |  |  |  |  | 290 |
Common stock dividends |  |  |  |  | (177 | ) |  |  |  | (177 | )
Capital contributions from parent |  |  | 345 |  |  |  |  |  |  | 345 |
Ending balance, September 30, 2020 |  | $33 |  |  |  | $2,693 |  |  |  | $1,004 |  |  |  | $200 |  |  |  | $3,930 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2018 |  | $33 |  |  |  | $2,223 |  |  |  | $775 |  |  |  | $200 |  |  |  | $3,231 |
Net income available for common stock |  |  |  |  | 239 |  |  |  |  | 239 |
Common stock dividends |  |  |  |  | (126 | ) |  |  |  | (126 | )
Capital contributions from parent |  |  | 100 |  |  |  |  |  |  | 100 |
Ending balance, September 30, 2019 |  | $33 |  |  |  | $2,323 |  |  |  | $888 |  |  |  | $200 |  |  |  | $3,444 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended September 30, 2020 |  |  |  |  |  |  |
Beginning balance, June 30, 2020 |  | $66 |  |  |  | $1,459 |  |  |  | $927 |  |  |  | $2,452 |
Net income |  |  |  |  | 73 |  |  | 73 |
Common stock dividends |  |  |  |  | (43 | ) |  | (43 | )
Ending balance, September 30, 2020 |  | $66 |  |  |  | $1,459 |  |  |  | $957 |  |  |  | $2,482 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Beginning balance, June 30, 2019 |  | $66 |  |  |  | $1,309 |  |  |  | $810 |  |  |  | $2,185 |
Net income |  |  |  |  | 76 |  |  | 76 |
Common stock dividends |  |  |  |  | (36 | ) |  | (36 | )
Capital contributions from parent |  |  | 100 |  |  |  |  | 100 |
Ending balance, September 30, 2019 |  | $66 |  |  |  | $1,409 |  |  |  | $850 |  |  |  | $2,325 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |
Beginning balance, December 31, 2019 |  | $66 |  |  |  | $1,434 |  |  |  | $864 |  |  |  | $2,364 |
Net income |  |  |  |  | 220 |  |  | 220 |
Common stock dividends |  |  |  |  | (127 | ) |  | (127 | )
Capital contributions from parent |  |  | 25 |  |  |  |  | 25 |
Ending balance, September 30, 2020 |  | $66 |  |  |  | $1,459 |  |  |  | $957 |  |  |  | $2,482 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Beginning balance, December 31, 2018 |  | $66 |  |  |  | $1,309 |  |  |  | $775 |  |  |  | $2,150 |
Net income |  |  |  |  | 183 |  |  | 183 |
Common stock dividends |  |  |  |  | (108 | ) |  | (108 | )
Capital contributions from parent |  |  | 100 |  |  |  |  | 100 |
Ending balance, September 30, 2019 |  | $66 |  |  |  | $1,409 |  |  |  | $850 |  |  |  | $2,325 |
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 September 30, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2020 |  | $2 |  |  |  | $2,683 |  |  |  | $2,874 |  |  |  | ($1 | ) |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,748 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 246 |  |  |  |  |  |  |  |  | 246 |
Common stock dividends ($0.38 per share) |  |  |  |  | (94 | ) |  |  |  |  |  |  |  | (94 | )
Shareowner Direct Plan issuances |  |  |  | 6 |  |  |  |  |  |  |  |  |  |  | 6 |
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  |  | (1 | ) |  |  |  | 3 |
Ending balance, September 30, 2020 |  | $2 |  |  |  | $2,693 |  |  |  | $3,026 |  |  |  | ($1 | ) |  |  | ($11 | ) |  |  | $200 |  |  |  | $5,909 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2019 |  | $2 |  |  |  | $2,109 |  |  |  | $2,598 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $4,900 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 226 |  |  |  |  |  |  |  |  | 226 |
Common stock dividends ($0.355 per share) |  |  |  |  | (85 | ) |  |  |  |  |  |  |  | (85 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 125 |  |  |  |  |  |  |  |  |  |  | 125 |
Equity-based compensation plans and other |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  | 3 |
Ending balance, September 30, 2019 |  | $2 |  |  |  | $2,237 |  |  |  | $2,739 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,169 |
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
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 |  | $2 |  |  |  | $2,446 |  |  |  | $2,766 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,405 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 550 |  |  |  |  |  |  |  |  | 550 |
Common stock dividends ($1.14 per share) |  |  |  |  | (281 | ) |  |  |  |  |  |  |  | (281 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 241 |  |  |  |  |  |  |  |  |  |  | 241 |
Equity-based compensation plans and other |  |  | 6 |  |  |  |  |  |  | (1 | ) |  |  |  | 5 |
Adoption of new accounting standard, net of tax (refer to Note 1(d)) |  |  |  |  | (9 | ) |  |  |  |  |  |  |  | (9 | )
Other comprehensive loss, net of tax |  |  |  |  |  |  | (2 | ) |  |  |  |  |  | (2 | )
Ending balance, September 30, 2020 |  | $2 |  |  |  | $2,693 |  |  |  | $3,026 |  |  |  | ($1 | ) |  |  | ($11 | ) |  |  | $200 |  |  |  | $5,909 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2018 |  | $2 |  |  |  | $2,046 |  |  |  | $2,546 |  |  |  | $2 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $4,786 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 446 |  |  |  |  |  |  |  |  | 446 |
Common stock dividends ($1.065 per share) |  |  |  |  | (253 | ) |  |  |  |  |  |  |  | (253 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  | 185 |  |  |  |  |  |  |  |  |  |  | 185 |
Equity-based compensation plans and other |  |  | 6 |  |  |  |  |  |  |  |  |  |  |  | 6 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1 | ) |  |  |  |  |  | (1 | )
Ending balance, September 30, 2019 |  | $2 |  |  |  | $2,237 |  |  |  | $2,739 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,169 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2020 |  | $33 |  |  |  | $2,523 |  |  |  | $915 |  |  |  | $200 |  |  |  | $3,671 |
Net income available for common stock |  |  |  |  | 148 |  |  |  |  | 148 |
Common stock dividends |  |  |  |  | (59 | ) |  |  |  | (59 | )
Capital contributions from parent |  |  | 170 |  |  |  |  |  |  | 170 |
Ending balance, September 30, 2020 |  | $33 |  |  |  | $2,693 |  |  |  | $1,004 |  |  |  | $200 |  |  |  | $3,930 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2019 |  | $33 |  |  |  | $2,323 |  |  |  | $789 |  |  |  | $200 |  |  |  | $3,345 |
Net income available for common stock |  |  |  |  | 141 |  |  |  |  | 141 |
Common stock dividends |  |  |  |  | (42 | ) |  |  |  | (42 | )
Ending balance, September 30, 2019 |  | $33 |  |  |  | $2,323 |  |  |  | $888 |  |  |  | $200 |  |  |  | $3,444 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 |  | $33 |  |  |  | $2,348 |  |  |  | $891 |  |  |  | $200 |  |  |  | $3,472 |
Net income available for common stock |  |  |  |  | 290 |  |  |  |  | 290 |
Common stock dividends |  |  |  |  | (177 | ) |  |  |  | (177 | )
Capital contributions from parent |  |  | 345 |  |  |  |  |  |  | 345 |
Ending balance, September 30, 2020 |  | $33 |  |  |  | $2,693 |  |  |  | $1,004 |  |  |  | $200 |  |  |  | $3,930 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2018 |  | $33 |  |  |  | $2,223 |  |  |  | $775 |  |  |  | $200 |  |  |  | $3,231 |
Net income available for common stock |  |  |  |  | 239 |  |  |  |  | 239 |
Common stock dividends |  |  |  |  | (126 | ) |  |  |  | (126 | )
Capital contributions from parent |  |  | 100 |  |  |  |  |  |  | 100 |
Ending balance, September 30, 2019 |  | $33 |  |  |  | $2,323 |  |  |  | $888 |  |  |  | $200 |  |  |  | $3,444 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended September 30, 2020 |  |  |  |  |  |  |
Beginning balance, June 30, 2020 |  | $66 |  |  |  | $1,459 |  |  |  | $927 |  |  |  | $2,452 |
Net income |  |  |  |  | 73 |  |  | 73 |
Common stock dividends |  |  |  |  | (43 | ) |  | (43 | )
Ending balance, September 30, 2020 |  | $66 |  |  |  | $1,459 |  |  |  | $957 |  |  |  | $2,482 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Beginning balance, June 30, 2019 |  | $66 |  |  |  | $1,309 |  |  |  | $810 |  |  |  | $2,185 |
Net income |  |  |  |  | 76 |  |  | 76 |
Common stock dividends |  |  |  |  | (36 | ) |  | (36 | )
Capital contributions from parent |  |  | 100 |  |  |  |  | 100 |
Ending balance, September 30, 2019 |  | $66 |  |  |  | $1,409 |  |  |  | $850 |  |  |  | $2,325 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |
Beginning balance, December 31, 2019 |  | $66 |  |  |  | $1,434 |  |  |  | $864 |  |  |  | $2,364 |
Net income |  |  |  |  | 220 |  |  | 220 |
Common stock dividends |  |  |  |  | (127 | ) |  | (127 | )
Capital contributions from parent |  |  | 25 |  |  |  |  | 25 |
Ending balance, September 30, 2020 |  | $66 |  |  |  | $1,459 |  |  |  | $957 |  |  |  | $2,482 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Beginning balance, December 31, 2018 |  | $66 |  |  |  | $1,309 |  |  |  | $775 |  |  |  | $2,150 |
Net income |  |  |  |  | 183 |  |  | 183 |
Common stock dividends |  |  |  |  | (108 | ) |  | (108 | )
Capital contributions from parent |  |  | 100 |  |  |  |  | 100 |
Ending balance, September 30, 2019 |  | $66 |  |  |  | $1,409 |  |  |  | $850 |  |  |  | $2,325 |
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 September 30, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2020 |  | $2 |  |  |  | $2,683 |  |  |  | $2,874 |  |  |  | ($1 | ) |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,748 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 246 |  |  |  |  |  |  |  |  | 246 |
Common stock dividends ($0.38 per share) |  |  |  |  | (94 | ) |  |  |  |  |  |  |  | (94 | )
Shareowner Direct Plan issuances |  |  |  | 6 |  |  |  |  |  |  |  |  |  |  | 6 |
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  |  | (1 | ) |  |  |  | 3 |
Ending balance, September 30, 2020 |  | $2 |  |  |  | $2,693 |  |  |  | $3,026 |  |  |  | ($1 | ) |  |  | ($11 | ) |  |  | $200 |  |  |  | $5,909 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2019 |  | $2 |  |  |  | $2,109 |  |  |  | $2,598 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $4,900 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 226 |  |  |  |  |  |  |  |  | 226 |
Common stock dividends ($0.355 per share) |  |  |  |  | (85 | ) |  |  |  |  |  |  |  | (85 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 125 |  |  |  |  |  |  |  |  |  |  | 125 |
Equity-based compensation plans and other |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  | 3 |
Ending balance, September 30, 2019 |  | $2 |  |  |  | $2,237 |  |  |  | $2,739 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,169 |
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
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 |  | $2 |  |  |  | $2,446 |  |  |  | $2,766 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,405 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 550 |  |  |  |  |  |  |  |  | 550 |
Common stock dividends ($1.14 per share) |  |  |  |  | (281 | ) |  |  |  |  |  |  |  | (281 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 241 |  |  |  |  |  |  |  |  |  |  | 241 |
Equity-based compensation plans and other |  |  | 6 |  |  |  |  |  |  | (1 | ) |  |  |  | 5 |
Adoption of new accounting standard, net of tax (refer to Note 1(d)) |  |  |  |  | (9 | ) |  |  |  |  |  |  |  | (9 | )
Other comprehensive loss, net of tax |  |  |  |  |  |  | (2 | ) |  |  |  |  |  | (2 | )
Ending balance, September 30, 2020 |  | $2 |  |  |  | $2,693 |  |  |  | $3,026 |  |  |  | ($1 | ) |  |  | ($11 | ) |  |  | $200 |  |  |  | $5,909 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2018 |  | $2 |  |  |  | $2,046 |  |  |  | $2,546 |  |  |  | $2 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $4,786 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 446 |  |  |  |  |  |  |  |  | 446 |
Common stock dividends ($1.065 per share) |  |  |  |  | (253 | ) |  |  |  |  |  |  |  | (253 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  | 185 |  |  |  |  |  |  |  |  |  |  | 185 |
Equity-based compensation plans and other |  |  | 6 |  |  |  |  |  |  |  |  |  |  |  | 6 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1 | ) |  |  |  |  |  | (1 | )
Ending balance, September 30, 2019 |  | $2 |  |  |  | $2,237 |  |  |  | $2,739 |  |  |  | $1 |  |  |  | ($10 | ) |  |  | $200 |  |  |  | $5,169 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2020 |  | $33 |  |  |  | $2,523 |  |  |  | $915 |  |  |  | $200 |  |  |  | $3,671 |
Net income available for common stock |  |  |  |  | 148 |  |  |  |  | 148 |
Common stock dividends |  |  |  |  | (59 | ) |  |  |  | (59 | )
Capital contributions from parent |  |  | 170 |  |  |  |  |  |  | 170 |
Ending balance, September 30, 2020 |  | $33 |  |  |  | $2,693 |  |  |  | $1,004 |  |  |  | $200 |  |  |  | $3,930 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2019 |  | $33 |  |  |  | $2,323 |  |  |  | $789 |  |  |  | $200 |  |  |  | $3,345 |
Net income available for common stock |  |  |  |  | 141 |  |  |  |  | 141 |
Common stock dividends |  |  |  |  | (42 | ) |  |  |  | (42 | )
Ending balance, September 30, 2019 |  | $33 |  |  |  | $2,323 |  |  |  | $888 |  |  |  | $200 |  |  |  | $3,444 |
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 |  | $33 |  |  |  | $2,348 |  |  |  | $891 |  |  |  | $200 |  |  |  | $3,472 |
Net income available for common stock |  |  |  |  | 290 |  |  |  |  | 290 |
Common stock dividends |  |  |  |  | (177 | ) |  |  |  | (177 | )
Capital contributions from parent |  |  | 345 |  |  |  |  |  |  | 345 |
Ending balance, September 30, 2020 |  | $33 |  |  |  | $2,693 |  |  |  | $1,004 |  |  |  | $200 |  |  |  | $3,930 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2018 |  | $33 |  |  |  | $2,223 |  |  |  | $775 |  |  |  | $200 |  |  |  | $3,231 |
Net income available for common stock |  |  |  |  | 239 |  |  |  |  | 239 |
Common stock dividends |  |  |  |  | (126 | ) |  |  |  | (126 | )
Capital contributions from parent |  |  | 100 |  |  |  |  |  |  | 100 |
Ending balance, September 30, 2019 |  | $33 |  |  |  | $2,323 |  |  |  | $888 |  |  |  | $200 |  |  |  | $3,444 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended September 30, 2020 |  |  |  |  |  |  |
Beginning balance, June 30, 2020 |  | $66 |  |  |  | $1,459 |  |  |  | $927 |  |  |  | $2,452 |
Net income |  |  |  |  | 73 |  |  | 73 |
Common stock dividends |  |  |  |  | (43 | ) |  | (43 | )
Ending balance, September 30, 2020 |  | $66 |  |  |  | $1,459 |  |  |  | $957 |  |  |  | $2,482 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Beginning balance, June 30, 2019 |  | $66 |  |  |  | $1,309 |  |  |  | $810 |  |  |  | $2,185 |
Net income |  |  |  |  | 76 |  |  | 76 |
Common stock dividends |  |  |  |  | (36 | ) |  | (36 | )
Capital contributions from parent |  |  | 100 |  |  |  |  | 100 |
Ending balance, September 30, 2019 |  | $66 |  |  |  | $1,409 |  |  |  | $850 |  |  |  | $2,325 |
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |
Beginning balance, December 31, 2019 |  | $66 |  |  |  | $1,434 |  |  |  | $864 |  |  |  | $2,364 |
Net income |  |  |  |  | 220 |  |  | 220 |
Common stock dividends |  |  |  |  | (127 | ) |  | (127 | )
Capital contributions from parent |  |  | 25 |  |  |  |  | 25 |
Ending balance, September 30, 2020 |  | $66 |  |  |  | $1,459 |  |  |  | $957 |  |  |  | $2,482 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Beginning balance, December 31, 2018 |  | $66 |  |  |  | $1,309 |  |  |  | $775 |  |  |  | $2,150 |
Net income |  |  |  |  | 183 |  |  | 183 |
Common stock dividends |  |  |  |  | (108 | ) |  | (108 | )
Capital contributions from parent |  |  | 100 |  |  |  |  | 100 |
Ending balance, September 30, 2019 |  | $66 |  |  |  | $1,409 |  |  |  | $850 |  |  |  | $2,325 |

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