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Common Equity (Tables) | 9 Months Ended
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Sep. 30, 2021
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, 2021 | 249,868,415 |
Shareowner Direct Plan | 378,823 |
Equity-based compensation plans | 113,549 |
Shares outstanding, September 30, 2021 | 250,360,787 |
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2021 | $3 |  | $2,722 |  | $3,106 |  | ($1) |  | ($11) |  | $200 |  | $6,019
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 256 |  |  |  |  |  |  |  | 256
Common stock dividends ($0.4025 per share) |  |  |  |  | (101) |  |  |  |  |  |  |  | (101)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 5 |  |  |  |  |  |  |  |  |  | 5
Ending balance, September 30, 2021 | $3 |  | $2,733 |  | $3,261 |  | ($1) |  | ($11) |  | $200 |  | $6,185
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
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $2 |  | $2,704 |  | $2,994 |  | ($1) |  | ($11) |  | $200 |  | $5,888
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 571 |  |  |  |  |  |  |  | 571
Common stock dividends ($1.2075 per share) |  |  |  |  | (304) |  |  |  |  |  |  |  | (304)
Shareowner Direct Plan issuances | 1 |  | 21 |  |  |  |  |  |  |  |  |  | 22
Equity-based compensation plans and other |  |  | 8 |  |  |  |  |  |  |  |  |  | 8
Ending balance, September 30, 2021 | $3 |  | $2,733 |  | $3,261 |  | ($1) |  | ($11) |  | $200 |  | $6,185
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 |  |  |  |  | (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
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended September 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2021 | $33 |  | $2,802 |  | $944 |  | $200 |  | $3,979
Net income available for common stock |  |  |  |  | 157 |  |  |  | 157
Common stock dividends |  |  |  |  | (101) |  |  |  | (101)
Ending balance, September 30, 2021 | $33 |  | $2,802 |  | $1,000 |  | $200 |  | $4,035
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
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Nine Months Ended September 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $33 |  | $2,752 |  | $979 |  | $200 |  | $3,964
Net income available for common stock |  |  |  |  | 322 |  |  |  | 322
Common stock dividends |  |  |  |  | (301) |  |  |  | (301)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, September 30, 2021 | $33 |  | $2,802 |  | $1,000 |  | $200 |  | $4,035
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
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended September 30, 2021 |  |  |  |  |  |  |
Beginning balance, June 30, 2021 | $66 |  | $1,669 |  | $990 |  | $2,725
Net income |  |  |  |  | 93 |  | 93
Common stock dividends |  |  |  |  | (41) |  | (41)
Capital contributions from parent |  |  | 35 |  |  |  | 35
Ending balance, September 30, 2021 | $66 |  | $1,704 |  | $1,042 |  | $2,812
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
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Nine Months Ended September 30, 2021 |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $66 |  | $1,459 |  | $953 |  | $2,478
Net income |  |  |  |  | 215 |  | 215
Common stock dividends |  |  |  |  | (126) |  | (126)
Capital contributions from parent |  |  | 245 |  |  |  | 245
Ending balance, September 30, 2021 | $66 |  | $1,704 |  | $1,042 |  | $2,812
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
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2021 | $3 |  | $2,722 |  | $3,106 |  | ($1) |  | ($11) |  | $200 |  | $6,019
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 256 |  |  |  |  |  |  |  | 256
Common stock dividends ($0.4025 per share) |  |  |  |  | (101) |  |  |  |  |  |  |  | (101)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 5 |  |  |  |  |  |  |  |  |  | 5
Ending balance, September 30, 2021 | $3 |  | $2,733 |  | $3,261 |  | ($1) |  | ($11) |  | $200 |  | $6,185
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
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $2 |  | $2,704 |  | $2,994 |  | ($1) |  | ($11) |  | $200 |  | $5,888
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 571 |  |  |  |  |  |  |  | 571
Common stock dividends ($1.2075 per share) |  |  |  |  | (304) |  |  |  |  |  |  |  | (304)
Shareowner Direct Plan issuances | 1 |  | 21 |  |  |  |  |  |  |  |  |  | 22
Equity-based compensation plans and other |  |  | 8 |  |  |  |  |  |  |  |  |  | 8
Ending balance, September 30, 2021 | $3 |  | $2,733 |  | $3,261 |  | ($1) |  | ($11) |  | $200 |  | $6,185
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 |  |  |  |  | (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
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended September 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2021 | $33 |  | $2,802 |  | $944 |  | $200 |  | $3,979
Net income available for common stock |  |  |  |  | 157 |  |  |  | 157
Common stock dividends |  |  |  |  | (101) |  |  |  | (101)
Ending balance, September 30, 2021 | $33 |  | $2,802 |  | $1,000 |  | $200 |  | $4,035
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
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Nine Months Ended September 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $33 |  | $2,752 |  | $979 |  | $200 |  | $3,964
Net income available for common stock |  |  |  |  | 322 |  |  |  | 322
Common stock dividends |  |  |  |  | (301) |  |  |  | (301)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, September 30, 2021 | $33 |  | $2,802 |  | $1,000 |  | $200 |  | $4,035
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
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended September 30, 2021 |  |  |  |  |  |  |
Beginning balance, June 30, 2021 | $66 |  | $1,669 |  | $990 |  | $2,725
Net income |  |  |  |  | 93 |  | 93
Common stock dividends |  |  |  |  | (41) |  | (41)
Capital contributions from parent |  |  | 35 |  |  |  | 35
Ending balance, September 30, 2021 | $66 |  | $1,704 |  | $1,042 |  | $2,812
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
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Nine Months Ended September 30, 2021 |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $66 |  | $1,459 |  | $953 |  | $2,478
Net income |  |  |  |  | 215 |  | 215
Common stock dividends |  |  |  |  | (126) |  | (126)
Capital contributions from parent |  |  | 245 |  |  |  | 245
Ending balance, September 30, 2021 | $66 |  | $1,704 |  | $1,042 |  | $2,812
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
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2021 | $3 |  | $2,722 |  | $3,106 |  | ($1) |  | ($11) |  | $200 |  | $6,019
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 256 |  |  |  |  |  |  |  | 256
Common stock dividends ($0.4025 per share) |  |  |  |  | (101) |  |  |  |  |  |  |  | (101)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 5 |  |  |  |  |  |  |  |  |  | 5
Ending balance, September 30, 2021 | $3 |  | $2,733 |  | $3,261 |  | ($1) |  | ($11) |  | $200 |  | $6,185
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
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $2 |  | $2,704 |  | $2,994 |  | ($1) |  | ($11) |  | $200 |  | $5,888
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 571 |  |  |  |  |  |  |  | 571
Common stock dividends ($1.2075 per share) |  |  |  |  | (304) |  |  |  |  |  |  |  | (304)
Shareowner Direct Plan issuances | 1 |  | 21 |  |  |  |  |  |  |  |  |  | 22
Equity-based compensation plans and other |  |  | 8 |  |  |  |  |  |  |  |  |  | 8
Ending balance, September 30, 2021 | $3 |  | $2,733 |  | $3,261 |  | ($1) |  | ($11) |  | $200 |  | $6,185
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 |  |  |  |  | (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
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended September 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2021 | $33 |  | $2,802 |  | $944 |  | $200 |  | $3,979
Net income available for common stock |  |  |  |  | 157 |  |  |  | 157
Common stock dividends |  |  |  |  | (101) |  |  |  | (101)
Ending balance, September 30, 2021 | $33 |  | $2,802 |  | $1,000 |  | $200 |  | $4,035
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
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Nine Months Ended September 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $33 |  | $2,752 |  | $979 |  | $200 |  | $3,964
Net income available for common stock |  |  |  |  | 322 |  |  |  | 322
Common stock dividends |  |  |  |  | (301) |  |  |  | (301)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, September 30, 2021 | $33 |  | $2,802 |  | $1,000 |  | $200 |  | $4,035
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
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended September 30, 2021 |  |  |  |  |  |  |
Beginning balance, June 30, 2021 | $66 |  | $1,669 |  | $990 |  | $2,725
Net income |  |  |  |  | 93 |  | 93
Common stock dividends |  |  |  |  | (41) |  | (41)
Capital contributions from parent |  |  | 35 |  |  |  | 35
Ending balance, September 30, 2021 | $66 |  | $1,704 |  | $1,042 |  | $2,812
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
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Nine Months Ended September 30, 2021 |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $66 |  | $1,459 |  | $953 |  | $2,478
Net income |  |  |  |  | 215 |  | 215
Common stock dividends |  |  |  |  | (126) |  | (126)
Capital contributions from parent |  |  | 245 |  |  |  | 245
Ending balance, September 30, 2021 | $66 |  | $1,704 |  | $1,042 |  | $2,812
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

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