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Common Equity | 3 Months Ended
--- | ---
Mar. 31, 2021
Common Equity [Line Items] |
Common Equity | COMMON EQUITY 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 | 152,588 |
Equity-based compensation plans | 113,549 |
Shares outstanding, March 31, 2021 | 250,134,552 |
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 March 31, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $2 |  | $2,704 |  | $2,994 |  | ($1) |  | ($11) |  | $200 |  | $5,888
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 171 |  |  |  |  |  |  |  | 171
Common stock dividends ($0.4025 per share) |  |  |  |  | (102) |  |  |  |  |  |  |  | (102)
Shareowner Direct Plan issuances | 1 |  | 7 |  |  |  |  |  |  |  |  |  | 8
Equity-based compensation plans and other |  |  | 1 |  |  |  |  |  |  |  |  |  | 1
Ending balance, March 31, 2021 | $3 |  | $2,712 |  | $3,063 |  | ($1) |  | ($11) |  | $200 |  | $5,966
Three Months Ended March 31, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $2 |  | $2,446 |  | $2,766 |  | $1 |  | ($10) |  | $200 |  | $5,405
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 170 |  |  |  |  |  |  |  | 170
Common stock dividends ($0.38 per share) |  |  |  |  | (93) |  |  |  |  |  |  |  | (93)
Equity forward settlements and Shareowner Direct Plan issuances |  |  | 228 |  |  |  |  |  |  |  |  |  | 228
Adoption of new accounting standard, net of tax |  |  |  |  | (9) |  |  |  |  |  |  |  | (9)
Other comprehensive income, net of tax |  |  |  |  |  |  | 1 |  |  |  |  |  | 1
Ending balance, March 31, 2020 | $2 |  | $2,674 |  | $2,834 |  | $2 |  | ($10) |  | $200 |  | $5,702
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended March 31, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $33 |  | $2,752 |  | $979 |  | $200 |  | $3,964
Net income available for common stock |  |  |  |  | 79 |  |  |  | 79
Common stock dividends |  |  |  |  | (101) |  |  |  | (101)
Ending balance, March 31, 2021 | $33 |  | $2,752 |  | $957 |  | $200 |  | $3,942
Three Months Ended March 31, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $33 |  | $2,348 |  | $891 |  | $200 |  | $3,472
Net income available for common stock |  |  |  |  | 83 |  |  |  | 83
Common stock dividends |  |  |  |  | (60) |  |  |  | (60)
Capital contributions from parent |  |  | 100 |  |  |  |  |  | 100
Ending balance, March 31, 2020 | $33 |  | $2,448 |  | $914 |  | $200 |  | $3,595
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended March 31, 2021 |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $66 |  | $1,459 |  | $953 |  | $2,478
Net income |  |  |  |  | 84 |  | 84
Common stock dividends |  |  |  |  | (42) |  | (42)
Capital contributions from parent |  |  | 125 |  |  |  | 125
Ending balance, March 31, 2021 | $66 |  | $1,584 |  | $995 |  | $2,645
Three Months Ended March 31, 2020 |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $66 |  | $1,434 |  | $864 |  | $2,364
Net income |  |  |  |  | 90 |  | 90
Common stock dividends |  |  |  |  | (43) |  | (43)
Capital contributions from parent |  |  | 25 |  |  |  | 25
Ending balance, March 31, 2020 | $66 |  | $1,459 |  | $911 |  | $2,436
IPL [Member] |
Common Equity [Line Items] |
Common Equity | COMMON EQUITY 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 | 152,588 |
Equity-based compensation plans | 113,549 |
Shares outstanding, March 31, 2021 | 250,134,552 |
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 March 31, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $2 |  | $2,704 |  | $2,994 |  | ($1) |  | ($11) |  | $200 |  | $5,888
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 171 |  |  |  |  |  |  |  | 171
Common stock dividends ($0.4025 per share) |  |  |  |  | (102) |  |  |  |  |  |  |  | (102)
Shareowner Direct Plan issuances | 1 |  | 7 |  |  |  |  |  |  |  |  |  | 8
Equity-based compensation plans and other |  |  | 1 |  |  |  |  |  |  |  |  |  | 1
Ending balance, March 31, 2021 | $3 |  | $2,712 |  | $3,063 |  | ($1) |  | ($11) |  | $200 |  | $5,966
Three Months Ended March 31, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $2 |  | $2,446 |  | $2,766 |  | $1 |  | ($10) |  | $200 |  | $5,405
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 170 |  |  |  |  |  |  |  | 170
Common stock dividends ($0.38 per share) |  |  |  |  | (93) |  |  |  |  |  |  |  | (93)
Equity forward settlements and Shareowner Direct Plan issuances |  |  | 228 |  |  |  |  |  |  |  |  |  | 228
Adoption of new accounting standard, net of tax |  |  |  |  | (9) |  |  |  |  |  |  |  | (9)
Other comprehensive income, net of tax |  |  |  |  |  |  | 1 |  |  |  |  |  | 1
Ending balance, March 31, 2020 | $2 |  | $2,674 |  | $2,834 |  | $2 |  | ($10) |  | $200 |  | $5,702
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended March 31, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $33 |  | $2,752 |  | $979 |  | $200 |  | $3,964
Net income available for common stock |  |  |  |  | 79 |  |  |  | 79
Common stock dividends |  |  |  |  | (101) |  |  |  | (101)
Ending balance, March 31, 2021 | $33 |  | $2,752 |  | $957 |  | $200 |  | $3,942
Three Months Ended March 31, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $33 |  | $2,348 |  | $891 |  | $200 |  | $3,472
Net income available for common stock |  |  |  |  | 83 |  |  |  | 83
Common stock dividends |  |  |  |  | (60) |  |  |  | (60)
Capital contributions from parent |  |  | 100 |  |  |  |  |  | 100
Ending balance, March 31, 2020 | $33 |  | $2,448 |  | $914 |  | $200 |  | $3,595
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended March 31, 2021 |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $66 |  | $1,459 |  | $953 |  | $2,478
Net income |  |  |  |  | 84 |  | 84
Common stock dividends |  |  |  |  | (42) |  | (42)
Capital contributions from parent |  |  | 125 |  |  |  | 125
Ending balance, March 31, 2021 | $66 |  | $1,584 |  | $995 |  | $2,645
Three Months Ended March 31, 2020 |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $66 |  | $1,434 |  | $864 |  | $2,364
Net income |  |  |  |  | 90 |  | 90
Common stock dividends |  |  |  |  | (43) |  | (43)
Capital contributions from parent |  |  | 25 |  |  |  | 25
Ending balance, March 31, 2020 | $66 |  | $1,459 |  | $911 |  | $2,436
WPL [Member] |
Common Equity [Line Items] |
Common Equity | COMMON EQUITY 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 | 152,588 |
Equity-based compensation plans | 113,549 |
Shares outstanding, March 31, 2021 | 250,134,552 |
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 March 31, 2021 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $2 |  | $2,704 |  | $2,994 |  | ($1) |  | ($11) |  | $200 |  | $5,888
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 171 |  |  |  |  |  |  |  | 171
Common stock dividends ($0.4025 per share) |  |  |  |  | (102) |  |  |  |  |  |  |  | (102)
Shareowner Direct Plan issuances | 1 |  | 7 |  |  |  |  |  |  |  |  |  | 8
Equity-based compensation plans and other |  |  | 1 |  |  |  |  |  |  |  |  |  | 1
Ending balance, March 31, 2021 | $3 |  | $2,712 |  | $3,063 |  | ($1) |  | ($11) |  | $200 |  | $5,966
Three Months Ended March 31, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $2 |  | $2,446 |  | $2,766 |  | $1 |  | ($10) |  | $200 |  | $5,405
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 170 |  |  |  |  |  |  |  | 170
Common stock dividends ($0.38 per share) |  |  |  |  | (93) |  |  |  |  |  |  |  | (93)
Equity forward settlements and Shareowner Direct Plan issuances |  |  | 228 |  |  |  |  |  |  |  |  |  | 228
Adoption of new accounting standard, net of tax |  |  |  |  | (9) |  |  |  |  |  |  |  | (9)
Other comprehensive income, net of tax |  |  |  |  |  |  | 1 |  |  |  |  |  | 1
Ending balance, March 31, 2020 | $2 |  | $2,674 |  | $2,834 |  | $2 |  | ($10) |  | $200 |  | $5,702
IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended March 31, 2021 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $33 |  | $2,752 |  | $979 |  | $200 |  | $3,964
Net income available for common stock |  |  |  |  | 79 |  |  |  | 79
Common stock dividends |  |  |  |  | (101) |  |  |  | (101)
Ending balance, March 31, 2021 | $33 |  | $2,752 |  | $957 |  | $200 |  | $3,942
Three Months Ended March 31, 2020 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $33 |  | $2,348 |  | $891 |  | $200 |  | $3,472
Net income available for common stock |  |  |  |  | 83 |  |  |  | 83
Common stock dividends |  |  |  |  | (60) |  |  |  | (60)
Capital contributions from parent |  |  | 100 |  |  |  |  |  | 100
Ending balance, March 31, 2020 | $33 |  | $2,448 |  | $914 |  | $200 |  | $3,595
WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended March 31, 2021 |  |  |  |  |  |  |
Beginning balance, December 31, 2020 | $66 |  | $1,459 |  | $953 |  | $2,478
Net income |  |  |  |  | 84 |  | 84
Common stock dividends |  |  |  |  | (42) |  | (42)
Capital contributions from parent |  |  | 125 |  |  |  | 125
Ending balance, March 31, 2021 | $66 |  | $1,584 |  | $995 |  | $2,645
Three Months Ended March 31, 2020 |  |  |  |  |  |  |
Beginning balance, December 31, 2019 | $66 |  | $1,434 |  | $864 |  | $2,364
Net income |  |  |  |  | 90 |  | 90
Common stock dividends |  |  |  |  | (43) |  | (43)
Capital contributions from parent |  |  | 25 |  |  |  | 25
Ending balance, March 31, 2020 | $66 |  | $1,459 |  | $911 |  | $2,436

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- Definition The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 14 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 18 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644 Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -URI http://asc.fasb.org/topic&trid=2208762 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 18 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 18 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 16 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496180-112644 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(e)(1)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 + Details
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