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Common Equity (Tables) | 6 Months Ended
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Jun. 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 | 275,892 |
Equity-based compensation plans | 113,549 |
Shares outstanding, June 30, 2021 | 250,257,856 |
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2021 | $3 |  | $2,712 |  | $3,063 |  | ($1) |  | ($11) |  | $200 |  | $5,966
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 144 |  |  |  |  |  |  |  | 144
Common stock dividends ($0.4025 per share) |  |  |  |  | (101) |  |  |  |  |  |  |  | (101)
Shareowner Direct Plan issuances |  |  | 7 |  |  |  |  |  |  |  |  |  | 7
Equity-based compensation plans and other |  |  | 3 |  |  |  |  |  |  |  |  |  | 3
Ending balance, June 30, 2021 | $3 |  | $2,722 |  | $3,106 |  | ($1) |  | ($11) |  | $200 |  | $6,019
Three Months Ended June 30, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2020 | $2 |  | $2,674 |  | $2,834 |  | $2 |  | ($10) |  | $200 |  | $5,702
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 134 |  |  |  |  |  |  |  | 134
Common stock dividends ($0.38 per share) |  |  |  |  | (94) |  |  |  |  |  |  |  | (94)
Shareowner Direct Plan issuances |  |  | 7 |  |  |  |  |  |  |  |  |  | 7
Equity-based compensation plans and other |  |  | 2 |  |  |  |  |  |  |  |  |  | 2
Other comprehensive loss, net of tax |  |  |  |  |  |  | (3) |  |  |  |  |  | (3)
Ending balance, June 30, 2020 | $2 |  | $2,683 |  | $2,874 |  | ($1) |  | ($10) |  | $200 |  | $5,748
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $2 |  | $2,704 |  | $2,994 |  | ($1) |  | ($11) |  | $200 |  | $5,888
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 315 |  |  |  |  |  |  |  | 315
Common stock dividends ($0.805 per share) |  |  |  |  | (203) |  |  |  |  |  |  |  | (203)
Shareowner Direct Plan issuances | 1 |  | 14 |  |  |  |  |  |  |  |  |  | 15
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  |  |  |  |  | 4
Ending balance, June 30, 2021 | $3 |  | $2,722 |  | $3,106 |  | ($1) |  | ($11) |  | $200 |  | $6,019
Six Months Ended June 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 |  |  |  |  | 304 |  |  |  |  |  |  |  | 304
Common stock dividends ($0.76 per share) |  |  |  |  | (187) |  |  |  |  |  |  |  | (187)
Equity forward settlements and Shareowner Direct Plan issuances |  |  | 235 |  |  |  |  |  |  |  |  |  | 235
Equity-based compensation plans and other |  |  | 2 |  |  |  |  |  |  |  |  |  | 2
Adoption of new accounting standard, net of tax |  |  |  |  | (9) |  |  |  |  |  |  |  | (9)
Other comprehensive loss, net of tax |  |  |  |  |  |  | (2) |  |  |  |  |  | (2)
Ending balance, June 30, 2020 | $2 |  | $2,683 |  | $2,874 |  | ($1) |  | ($10) |  | $200 |  | $5,748
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended June 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2021 | $33 |  | $2,752 |  | $957 |  | $200 |  | $3,942
Net income available for common stock |  |  |  |  | 86 |  |  |  | 86
Common stock dividends |  |  |  |  | (99) |  |  |  | (99)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, June 30, 2021 | $33 |  | $2,802 |  | $944 |  | $200 |  | $3,979
Three Months Ended June 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2020 | $33 |  | $2,448 |  | $914 |  | $200 |  | $3,595
Net income available for common stock |  |  |  |  | 60 |  |  |  | 60
Common stock dividends |  |  |  |  | (59) |  |  |  | (59)
Capital contributions from parent |  |  | 75 |  |  |  |  |  | 75
Ending balance, June 30, 2020 | $33 |  | $2,523 |  | $915 |  | $200 |  | $3,671
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Six Months Ended June 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $33 |  | $2,752 |  | $979 |  | $200 |  | $3,964
Net income available for common stock |  |  |  |  | 165 |  |  |  | 165
Common stock dividends |  |  |  |  | (200) |  |  |  | (200)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, June 30, 2021 | $33 |  | $2,802 |  | $944 |  | $200 |  | $3,979
Six Months Ended June 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $33 |  | $2,348 |  | $891 |  | $200 |  | $3,472
Net income available for common stock |  |  |  |  | 142 |  |  |  | 142
Common stock dividends |  |  |  |  | (118) |  |  |  | (118)
Capital contributions from parent |  |  | 175 |  |  |  |  |  | 175
Ending balance, June 30, 2020 | $33 |  | $2,523 |  | $915 |  | $200 |  | $3,671
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended June 30, 2021 |  |  |  |  |  |  |
Beginning balance, March 31, 2021 | $66 |  | $1,584 |  | $995 |  | $2,645
Net income |  |  |  |  | 38 |  | 38
Common stock dividends |  |  |  |  | (43) |  | (43)
Capital contributions from parent |  |  | 85 |  |  |  | 85
Ending balance, June 30, 2021 | $66 |  | $1,669 |  | $990 |  | $2,725
Three Months Ended June 30, 2020 |  |  |  |  |  |  |
Beginning balance, March 31, 2020 | $66 |  | $1,459 |  | $911 |  | $2,436
Net income |  |  |  |  | 58 |  | 58
Common stock dividends |  |  |  |  | (42) |  | (42)
Ending balance, June 30, 2020 | $66 |  | $1,459 |  | $927 |  | $2,452
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Six Months Ended June 30, 2021 |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $66 |  | $1,459 |  | $953 |  | $2,478
Net income |  |  |  |  | 122 |  | 122
Common stock dividends |  |  |  |  | (85) |  | (85)
Capital contributions from parent |  |  | 210 |  |  |  | 210
Ending balance, June 30, 2021 | $66 |  | $1,669 |  | $990 |  | $2,725
Six Months Ended June 30, 2020 |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $66 |  | $1,434 |  | $864 |  | $2,364
Net income |  |  |  |  | 147 |  | 147
Common stock dividends |  |  |  |  | (84) |  | (84)
Capital contributions from parent |  |  | 25 |  |  |  | 25
Ending balance, June 30, 2020 | $66 |  | $1,459 |  | $927 |  | $2,452
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2021 | $3 |  | $2,712 |  | $3,063 |  | ($1) |  | ($11) |  | $200 |  | $5,966
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 144 |  |  |  |  |  |  |  | 144
Common stock dividends ($0.4025 per share) |  |  |  |  | (101) |  |  |  |  |  |  |  | (101)
Shareowner Direct Plan issuances |  |  | 7 |  |  |  |  |  |  |  |  |  | 7
Equity-based compensation plans and other |  |  | 3 |  |  |  |  |  |  |  |  |  | 3
Ending balance, June 30, 2021 | $3 |  | $2,722 |  | $3,106 |  | ($1) |  | ($11) |  | $200 |  | $6,019
Three Months Ended June 30, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2020 | $2 |  | $2,674 |  | $2,834 |  | $2 |  | ($10) |  | $200 |  | $5,702
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 134 |  |  |  |  |  |  |  | 134
Common stock dividends ($0.38 per share) |  |  |  |  | (94) |  |  |  |  |  |  |  | (94)
Shareowner Direct Plan issuances |  |  | 7 |  |  |  |  |  |  |  |  |  | 7
Equity-based compensation plans and other |  |  | 2 |  |  |  |  |  |  |  |  |  | 2
Other comprehensive loss, net of tax |  |  |  |  |  |  | (3) |  |  |  |  |  | (3)
Ending balance, June 30, 2020 | $2 |  | $2,683 |  | $2,874 |  | ($1) |  | ($10) |  | $200 |  | $5,748
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $2 |  | $2,704 |  | $2,994 |  | ($1) |  | ($11) |  | $200 |  | $5,888
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 315 |  |  |  |  |  |  |  | 315
Common stock dividends ($0.805 per share) |  |  |  |  | (203) |  |  |  |  |  |  |  | (203)
Shareowner Direct Plan issuances | 1 |  | 14 |  |  |  |  |  |  |  |  |  | 15
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  |  |  |  |  | 4
Ending balance, June 30, 2021 | $3 |  | $2,722 |  | $3,106 |  | ($1) |  | ($11) |  | $200 |  | $6,019
Six Months Ended June 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 |  |  |  |  | 304 |  |  |  |  |  |  |  | 304
Common stock dividends ($0.76 per share) |  |  |  |  | (187) |  |  |  |  |  |  |  | (187)
Equity forward settlements and Shareowner Direct Plan issuances |  |  | 235 |  |  |  |  |  |  |  |  |  | 235
Equity-based compensation plans and other |  |  | 2 |  |  |  |  |  |  |  |  |  | 2
Adoption of new accounting standard, net of tax |  |  |  |  | (9) |  |  |  |  |  |  |  | (9)
Other comprehensive loss, net of tax |  |  |  |  |  |  | (2) |  |  |  |  |  | (2)
Ending balance, June 30, 2020 | $2 |  | $2,683 |  | $2,874 |  | ($1) |  | ($10) |  | $200 |  | $5,748
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended June 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2021 | $33 |  | $2,752 |  | $957 |  | $200 |  | $3,942
Net income available for common stock |  |  |  |  | 86 |  |  |  | 86
Common stock dividends |  |  |  |  | (99) |  |  |  | (99)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, June 30, 2021 | $33 |  | $2,802 |  | $944 |  | $200 |  | $3,979
Three Months Ended June 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2020 | $33 |  | $2,448 |  | $914 |  | $200 |  | $3,595
Net income available for common stock |  |  |  |  | 60 |  |  |  | 60
Common stock dividends |  |  |  |  | (59) |  |  |  | (59)
Capital contributions from parent |  |  | 75 |  |  |  |  |  | 75
Ending balance, June 30, 2020 | $33 |  | $2,523 |  | $915 |  | $200 |  | $3,671
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Six Months Ended June 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $33 |  | $2,752 |  | $979 |  | $200 |  | $3,964
Net income available for common stock |  |  |  |  | 165 |  |  |  | 165
Common stock dividends |  |  |  |  | (200) |  |  |  | (200)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, June 30, 2021 | $33 |  | $2,802 |  | $944 |  | $200 |  | $3,979
Six Months Ended June 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $33 |  | $2,348 |  | $891 |  | $200 |  | $3,472
Net income available for common stock |  |  |  |  | 142 |  |  |  | 142
Common stock dividends |  |  |  |  | (118) |  |  |  | (118)
Capital contributions from parent |  |  | 175 |  |  |  |  |  | 175
Ending balance, June 30, 2020 | $33 |  | $2,523 |  | $915 |  | $200 |  | $3,671
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended June 30, 2021 |  |  |  |  |  |  |
Beginning balance, March 31, 2021 | $66 |  | $1,584 |  | $995 |  | $2,645
Net income |  |  |  |  | 38 |  | 38
Common stock dividends |  |  |  |  | (43) |  | (43)
Capital contributions from parent |  |  | 85 |  |  |  | 85
Ending balance, June 30, 2021 | $66 |  | $1,669 |  | $990 |  | $2,725
Three Months Ended June 30, 2020 |  |  |  |  |  |  |
Beginning balance, March 31, 2020 | $66 |  | $1,459 |  | $911 |  | $2,436
Net income |  |  |  |  | 58 |  | 58
Common stock dividends |  |  |  |  | (42) |  | (42)
Ending balance, June 30, 2020 | $66 |  | $1,459 |  | $927 |  | $2,452
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Six Months Ended June 30, 2021 |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $66 |  | $1,459 |  | $953 |  | $2,478
Net income |  |  |  |  | 122 |  | 122
Common stock dividends |  |  |  |  | (85) |  | (85)
Capital contributions from parent |  |  | 210 |  |  |  | 210
Ending balance, June 30, 2021 | $66 |  | $1,669 |  | $990 |  | $2,725
Six Months Ended June 30, 2020 |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $66 |  | $1,434 |  | $864 |  | $2,364
Net income |  |  |  |  | 147 |  | 147
Common stock dividends |  |  |  |  | (84) |  | (84)
Capital contributions from parent |  |  | 25 |  |  |  | 25
Ending balance, June 30, 2020 | $66 |  | $1,459 |  | $927 |  | $2,452
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2021 | $3 |  | $2,712 |  | $3,063 |  | ($1) |  | ($11) |  | $200 |  | $5,966
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 144 |  |  |  |  |  |  |  | 144
Common stock dividends ($0.4025 per share) |  |  |  |  | (101) |  |  |  |  |  |  |  | (101)
Shareowner Direct Plan issuances |  |  | 7 |  |  |  |  |  |  |  |  |  | 7
Equity-based compensation plans and other |  |  | 3 |  |  |  |  |  |  |  |  |  | 3
Ending balance, June 30, 2021 | $3 |  | $2,722 |  | $3,106 |  | ($1) |  | ($11) |  | $200 |  | $6,019
Three Months Ended June 30, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2020 | $2 |  | $2,674 |  | $2,834 |  | $2 |  | ($10) |  | $200 |  | $5,702
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 134 |  |  |  |  |  |  |  | 134
Common stock dividends ($0.38 per share) |  |  |  |  | (94) |  |  |  |  |  |  |  | (94)
Shareowner Direct Plan issuances |  |  | 7 |  |  |  |  |  |  |  |  |  | 7
Equity-based compensation plans and other |  |  | 2 |  |  |  |  |  |  |  |  |  | 2
Other comprehensive loss, net of tax |  |  |  |  |  |  | (3) |  |  |  |  |  | (3)
Ending balance, June 30, 2020 | $2 |  | $2,683 |  | $2,874 |  | ($1) |  | ($10) |  | $200 |  | $5,748
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, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $2 |  | $2,704 |  | $2,994 |  | ($1) |  | ($11) |  | $200 |  | $5,888
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 315 |  |  |  |  |  |  |  | 315
Common stock dividends ($0.805 per share) |  |  |  |  | (203) |  |  |  |  |  |  |  | (203)
Shareowner Direct Plan issuances | 1 |  | 14 |  |  |  |  |  |  |  |  |  | 15
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  |  |  |  |  | 4
Ending balance, June 30, 2021 | $3 |  | $2,722 |  | $3,106 |  | ($1) |  | ($11) |  | $200 |  | $6,019
Six Months Ended June 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 |  |  |  |  | 304 |  |  |  |  |  |  |  | 304
Common stock dividends ($0.76 per share) |  |  |  |  | (187) |  |  |  |  |  |  |  | (187)
Equity forward settlements and Shareowner Direct Plan issuances |  |  | 235 |  |  |  |  |  |  |  |  |  | 235
Equity-based compensation plans and other |  |  | 2 |  |  |  |  |  |  |  |  |  | 2
Adoption of new accounting standard, net of tax |  |  |  |  | (9) |  |  |  |  |  |  |  | (9)
Other comprehensive loss, net of tax |  |  |  |  |  |  | (2) |  |  |  |  |  | (2)
Ending balance, June 30, 2020 | $2 |  | $2,683 |  | $2,874 |  | ($1) |  | ($10) |  | $200 |  | $5,748
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended June 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2021 | $33 |  | $2,752 |  | $957 |  | $200 |  | $3,942
Net income available for common stock |  |  |  |  | 86 |  |  |  | 86
Common stock dividends |  |  |  |  | (99) |  |  |  | (99)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, June 30, 2021 | $33 |  | $2,802 |  | $944 |  | $200 |  | $3,979
Three Months Ended June 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2020 | $33 |  | $2,448 |  | $914 |  | $200 |  | $3,595
Net income available for common stock |  |  |  |  | 60 |  |  |  | 60
Common stock dividends |  |  |  |  | (59) |  |  |  | (59)
Capital contributions from parent |  |  | 75 |  |  |  |  |  | 75
Ending balance, June 30, 2020 | $33 |  | $2,523 |  | $915 |  | $200 |  | $3,671
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Six Months Ended June 30, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $33 |  | $2,752 |  | $979 |  | $200 |  | $3,964
Net income available for common stock |  |  |  |  | 165 |  |  |  | 165
Common stock dividends |  |  |  |  | (200) |  |  |  | (200)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, June 30, 2021 | $33 |  | $2,802 |  | $944 |  | $200 |  | $3,979
Six Months Ended June 30, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $33 |  | $2,348 |  | $891 |  | $200 |  | $3,472
Net income available for common stock |  |  |  |  | 142 |  |  |  | 142
Common stock dividends |  |  |  |  | (118) |  |  |  | (118)
Capital contributions from parent |  |  | 175 |  |  |  |  |  | 175
Ending balance, June 30, 2020 | $33 |  | $2,523 |  | $915 |  | $200 |  | $3,671
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended June 30, 2021 |  |  |  |  |  |  |
Beginning balance, March 31, 2021 | $66 |  | $1,584 |  | $995 |  | $2,645
Net income |  |  |  |  | 38 |  | 38
Common stock dividends |  |  |  |  | (43) |  | (43)
Capital contributions from parent |  |  | 85 |  |  |  | 85
Ending balance, June 30, 2021 | $66 |  | $1,669 |  | $990 |  | $2,725
Three Months Ended June 30, 2020 |  |  |  |  |  |  |
Beginning balance, March 31, 2020 | $66 |  | $1,459 |  | $911 |  | $2,436
Net income |  |  |  |  | 58 |  | 58
Common stock dividends |  |  |  |  | (42) |  | (42)
Ending balance, June 30, 2020 | $66 |  | $1,459 |  | $927 |  | $2,452
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Six Months Ended June 30, 2021 |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $66 |  | $1,459 |  | $953 |  | $2,478
Net income |  |  |  |  | 122 |  | 122
Common stock dividends |  |  |  |  | (85) |  | (85)
Capital contributions from parent |  |  | 210 |  |  |  | 210
Ending balance, June 30, 2021 | $66 |  | $1,669 |  | $990 |  | $2,725
Six Months Ended June 30, 2020 |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $66 |  | $1,434 |  | $864 |  | $2,364
Net income |  |  |  |  | 147 |  | 147
Common stock dividends |  |  |  |  | (84) |  | (84)
Capital contributions from parent |  |  | 25 |  |  |  | 25
Ending balance, June 30, 2020 | $66 |  | $1,459 |  | $927 |  | $2,452

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