XML 30 R11.htm IDEA: XBRL DOCUMENT
v3.23.2

Common Equity | 6 Months Ended
--- | ---
Jun. 30, 2023
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, 2023 | 251,134,966 |
At-the-market offering program | 1,221,775 |
Shareowner Direct Plan | 228,017 |
Equity-based compensation plans | 134,334 |
Shares outstanding, June 30, 2023 | 252,719,092 |
At-the-Market Offering Program - In December 2022, Alliant Energy filed a prospectus supplement under which it may sell up to $225 million of its common stock through an at-the-market offering program. As of June 30, 2023, Alliant Energy issued 1,221,775 shares of common stock through this program and received cash proceeds of $64 million, net of $1 million in commissions and fees. Alliant Energy also had commitments not recognized on its balance sheet at June 30, 2023 to sell 172,701 shares of common stock under sales transactions executed through this program in late June 2023. Subsequent to June 30, 2023, Alliant Energy issued shares to settle these transactions in exchange for net cash proceeds of $9 million. The proceeds from the issuances of common stock were used for general corporate purposes. 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 |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | Interest |  | Equity
Three Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2023 | $3 |  | $2,780 |  | $3,559 |  | ($1) |  | ($13) |  | $— |  | $6,328
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 160 |  |  |  |  |  |  |  | 160
Common stock dividends ($0.4525 per share) |  |  |  |  | (113) |  |  |  |  |  |  |  | (113)
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 70 |  |  |  |  |  |  |  |  |  | 70
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  | (1) |  |  |  | 3
Other comprehensive income, net of tax |  |  |  |  |  |  | 4 |  |  |  |  |  | 4
Ending balance, June 30, 2023 | $3 |  | $2,854 |  | $3,606 |  | $3 |  | ($14) |  | $— |  | $6,452
Three Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2022 | $3 |  | $2,750 |  | $3,336 |  | $— |  | ($12) |  | $— |  | $6,077
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 159 |  |  |  |  |  |  |  | 159
Common stock dividends ($0.4275 per share) |  |  |  |  | (108) |  |  |  |  |  |  |  | (108)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 3 |  |  |  |  |  |  |  |  |  | 3
Contributions from noncontrolling interest |  |  |  |  |  |  |  |  |  |  | 29 |  | 29
Ending balance, June 30, 2022 | $3 |  | $2,759 |  | $3,387 |  | $— |  | ($12) |  | $29 |  | $6,166
Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | Interest |  | Equity
Six Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $3 |  | $2,777 |  | $3,509 |  | $— |  | ($13) |  | $— |  | $6,276
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 323 |  |  |  |  |  |  |  | 323
Common stock dividends ($0.905 per share) |  |  |  |  | (226) |  |  |  |  |  |  |  | (226)
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 76 |  |  |  |  |  |  |  |  |  | 76
Equity-based compensation plans and other |  |  | 1 |  |  |  |  |  | (1) |  |  |  | —
Other comprehensive income, net of tax |  |  |  |  |  |  | 3 |  |  |  |  |  | 3
Ending balance, June 30, 2023 | $3 |  | $2,854 |  | $3,606 |  | $3 |  | ($14) |  | $— |  | $6,452
Six Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2021 | $3 |  | $2,749 |  | $3,250 |  | $— |  | ($12) |  | $— |  | $5,990
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 351 |  |  |  |  |  |  |  | 351
Common stock dividends ($0.855 per share) |  |  |  |  | (215) |  |  |  |  |  |  |  | (215)
Shareowner Direct Plan issuances |  |  | 13 |  |  |  |  |  |  |  |  |  | 13
Equity-based compensation plans and other |  |  | (3) |  | 1 |  |  |  |  |  |  |  | (2)
Contributions from noncontrolling interest |  |  |  |  |  |  |  |  |  |  | 29 |  | 29
Ending balance, June 30, 2022 | $3 |  | $2,759 |  | $3,387 |  | $— |  | ($12) |  | $29 |  | $6,166
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2023 | $33 |  | $2,807 |  | $970 |  |  |  | $3,810
Net income |  |  |  |  | 89 |  |  |  | 89
Common stock dividends |  |  |  |  | (70) |  |  |  | (70)
Capital contributions from parent |  |  | 40 |  |  |  |  |  | 40
Ending balance, June 30, 2023 | $33 |  | $2,847 |  | $989 |  |  |  | $3,869
Three Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2022 | $33 |  | $2,807 |  | $935 |  |  |  | $3,775
Net income |  |  |  |  | 87 |  |  |  | 87
Common stock dividends |  |  |  |  | (80) |  |  |  | (80)
Ending balance, June 30, 2022 | $33 |  | $2,807 |  | $942 |  |  |  | $3,782
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Six Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $33 |  | $2,807 |  | $968 |  |  |  | $3,808
Net income |  |  |  |  | 161 |  |  |  | 161
Common stock dividends |  |  |  |  | (140) |  |  |  | (140)
Capital contributions from parent |  |  | 40 |  |  |  |  |  | 40
Ending balance, June 30, 2023 | $33 |  | $2,847 |  | $989 |  |  |  | $3,869
Six Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2021 | $33 |  | $2,807 |  | $929 |  |  |  | $3,769
Net income |  |  |  |  | 173 |  |  |  | 173
Common stock dividends |  |  |  |  | (160) |  |  |  | (160)
Ending balance, June 30, 2022 | $33 |  | $2,807 |  | $942 |  |  |  | $3,782
WPL | Total WPL Common Equity |  |  |  |
|  |  | Additional |  |  |  |  |  |
| Common |  | Paid-In |  | Retained |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Interest |  | Equity
Three Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2023 | $66 |  | $2,413 |  | $1,234 |  | $— |  | $3,713
Net income |  |  |  |  | 72 |  |  |  | 72
Common stock dividends |  |  |  |  | (46) |  |  |  | (46)
Ending balance, June 30, 2023 | $66 |  | $2,413 |  | $1,260 |  | $— |  | $3,739
Three Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2022 | $66 |  | $1,884 |  | $1,101 |  | $— |  | $3,051
Net income |  |  |  |  | 63 |  |  |  | 63
Common stock dividends |  |  |  |  | (44) |  |  |  | (44)
Capital contributions from parent |  |  | 85 |  |  |  |  |  | 85
Contributions from noncontrolling interest |  |  |  |  |  |  | 29 |  | 29
Other |  |  | (1) |  |  |  |  |  | (1)
Ending balance, June 30, 2022 | $66 |  | $1,968 |  | $1,120 |  | $29 |  | $3,183
WPL | Total WPL Common Equity |  |  |  |
|  |  | Additional |  |  |  |  |  |
| Common |  | Paid-In |  | Retained |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Interest |  | Equity
Six Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $66 |  | $2,233 |  | $1,192 |  | $— |  | $3,491
Net income |  |  |  |  | 160 |  |  |  | 160
Common stock dividends |  |  |  |  | (92) |  |  |  | (92)
Capital contributions from parent |  |  | 180 |  |  |  |  |  | 180
Ending balance, June 30, 2023 | $66 |  | $2,413 |  | $1,260 |  | $— |  | $3,739
Six Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2021 | $66 |  | $1,704 |  | $1,053 |  | $— |  | $2,823
Net income |  |  |  |  | 156 |  |  |  | 156
Common stock dividends |  |  |  |  | (89) |  |  |  | (89)
Capital contributions from parent |  |  | 265 |  |  |  |  |  | 265
Contributions from noncontrolling interest |  |  |  |  |  |  | 29 |  | 29
Other |  |  | (1) |  |  |  |  |  | (1)
Ending balance, June 30, 2022 | $66 |  | $1,968 |  | $1,120 |  | $29 |  | $3,183
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, 2023 | 251,134,966 |
At-the-market offering program | 1,221,775 |
Shareowner Direct Plan | 228,017 |
Equity-based compensation plans | 134,334 |
Shares outstanding, June 30, 2023 | 252,719,092 |
At-the-Market Offering Program - In December 2022, Alliant Energy filed a prospectus supplement under which it may sell up to $225 million of its common stock through an at-the-market offering program. As of June 30, 2023, Alliant Energy issued 1,221,775 shares of common stock through this program and received cash proceeds of $64 million, net of $1 million in commissions and fees. Alliant Energy also had commitments not recognized on its balance sheet at June 30, 2023 to sell 172,701 shares of common stock under sales transactions executed through this program in late June 2023. Subsequent to June 30, 2023, Alliant Energy issued shares to settle these transactions in exchange for net cash proceeds of $9 million. The proceeds from the issuances of common stock were used for general corporate purposes. 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 |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | Interest |  | Equity
Three Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2023 | $3 |  | $2,780 |  | $3,559 |  | ($1) |  | ($13) |  | $— |  | $6,328
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 160 |  |  |  |  |  |  |  | 160
Common stock dividends ($0.4525 per share) |  |  |  |  | (113) |  |  |  |  |  |  |  | (113)
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 70 |  |  |  |  |  |  |  |  |  | 70
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  | (1) |  |  |  | 3
Other comprehensive income, net of tax |  |  |  |  |  |  | 4 |  |  |  |  |  | 4
Ending balance, June 30, 2023 | $3 |  | $2,854 |  | $3,606 |  | $3 |  | ($14) |  | $— |  | $6,452
Three Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2022 | $3 |  | $2,750 |  | $3,336 |  | $— |  | ($12) |  | $— |  | $6,077
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 159 |  |  |  |  |  |  |  | 159
Common stock dividends ($0.4275 per share) |  |  |  |  | (108) |  |  |  |  |  |  |  | (108)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 3 |  |  |  |  |  |  |  |  |  | 3
Contributions from noncontrolling interest |  |  |  |  |  |  |  |  |  |  | 29 |  | 29
Ending balance, June 30, 2022 | $3 |  | $2,759 |  | $3,387 |  | $— |  | ($12) |  | $29 |  | $6,166
Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | Interest |  | Equity
Six Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $3 |  | $2,777 |  | $3,509 |  | $— |  | ($13) |  | $— |  | $6,276
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 323 |  |  |  |  |  |  |  | 323
Common stock dividends ($0.905 per share) |  |  |  |  | (226) |  |  |  |  |  |  |  | (226)
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 76 |  |  |  |  |  |  |  |  |  | 76
Equity-based compensation plans and other |  |  | 1 |  |  |  |  |  | (1) |  |  |  | —
Other comprehensive income, net of tax |  |  |  |  |  |  | 3 |  |  |  |  |  | 3
Ending balance, June 30, 2023 | $3 |  | $2,854 |  | $3,606 |  | $3 |  | ($14) |  | $— |  | $6,452
Six Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2021 | $3 |  | $2,749 |  | $3,250 |  | $— |  | ($12) |  | $— |  | $5,990
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 351 |  |  |  |  |  |  |  | 351
Common stock dividends ($0.855 per share) |  |  |  |  | (215) |  |  |  |  |  |  |  | (215)
Shareowner Direct Plan issuances |  |  | 13 |  |  |  |  |  |  |  |  |  | 13
Equity-based compensation plans and other |  |  | (3) |  | 1 |  |  |  |  |  |  |  | (2)
Contributions from noncontrolling interest |  |  |  |  |  |  |  |  |  |  | 29 |  | 29
Ending balance, June 30, 2022 | $3 |  | $2,759 |  | $3,387 |  | $— |  | ($12) |  | $29 |  | $6,166
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2023 | $33 |  | $2,807 |  | $970 |  |  |  | $3,810
Net income |  |  |  |  | 89 |  |  |  | 89
Common stock dividends |  |  |  |  | (70) |  |  |  | (70)
Capital contributions from parent |  |  | 40 |  |  |  |  |  | 40
Ending balance, June 30, 2023 | $33 |  | $2,847 |  | $989 |  |  |  | $3,869
Three Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2022 | $33 |  | $2,807 |  | $935 |  |  |  | $3,775
Net income |  |  |  |  | 87 |  |  |  | 87
Common stock dividends |  |  |  |  | (80) |  |  |  | (80)
Ending balance, June 30, 2022 | $33 |  | $2,807 |  | $942 |  |  |  | $3,782
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Six Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $33 |  | $2,807 |  | $968 |  |  |  | $3,808
Net income |  |  |  |  | 161 |  |  |  | 161
Common stock dividends |  |  |  |  | (140) |  |  |  | (140)
Capital contributions from parent |  |  | 40 |  |  |  |  |  | 40
Ending balance, June 30, 2023 | $33 |  | $2,847 |  | $989 |  |  |  | $3,869
Six Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2021 | $33 |  | $2,807 |  | $929 |  |  |  | $3,769
Net income |  |  |  |  | 173 |  |  |  | 173
Common stock dividends |  |  |  |  | (160) |  |  |  | (160)
Ending balance, June 30, 2022 | $33 |  | $2,807 |  | $942 |  |  |  | $3,782
WPL | Total WPL Common Equity |  |  |  |
|  |  | Additional |  |  |  |  |  |
| Common |  | Paid-In |  | Retained |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Interest |  | Equity
Three Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2023 | $66 |  | $2,413 |  | $1,234 |  | $— |  | $3,713
Net income |  |  |  |  | 72 |  |  |  | 72
Common stock dividends |  |  |  |  | (46) |  |  |  | (46)
Ending balance, June 30, 2023 | $66 |  | $2,413 |  | $1,260 |  | $— |  | $3,739
Three Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2022 | $66 |  | $1,884 |  | $1,101 |  | $— |  | $3,051
Net income |  |  |  |  | 63 |  |  |  | 63
Common stock dividends |  |  |  |  | (44) |  |  |  | (44)
Capital contributions from parent |  |  | 85 |  |  |  |  |  | 85
Contributions from noncontrolling interest |  |  |  |  |  |  | 29 |  | 29
Other |  |  | (1) |  |  |  |  |  | (1)
Ending balance, June 30, 2022 | $66 |  | $1,968 |  | $1,120 |  | $29 |  | $3,183
WPL | Total WPL Common Equity |  |  |  |
|  |  | Additional |  |  |  |  |  |
| Common |  | Paid-In |  | Retained |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Interest |  | Equity
Six Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $66 |  | $2,233 |  | $1,192 |  | $— |  | $3,491
Net income |  |  |  |  | 160 |  |  |  | 160
Common stock dividends |  |  |  |  | (92) |  |  |  | (92)
Capital contributions from parent |  |  | 180 |  |  |  |  |  | 180
Ending balance, June 30, 2023 | $66 |  | $2,413 |  | $1,260 |  | $— |  | $3,739
Six Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2021 | $66 |  | $1,704 |  | $1,053 |  | $— |  | $2,823
Net income |  |  |  |  | 156 |  |  |  | 156
Common stock dividends |  |  |  |  | (89) |  |  |  | (89)
Capital contributions from parent |  |  | 265 |  |  |  |  |  | 265
Contributions from noncontrolling interest |  |  |  |  |  |  | 29 |  | 29
Other |  |  | (1) |  |  |  |  |  | (1)
Ending balance, June 30, 2022 | $66 |  | $1,968 |  | $1,120 |  | $29 |  | $3,183
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, 2023 | 251,134,966 |
At-the-market offering program | 1,221,775 |
Shareowner Direct Plan | 228,017 |
Equity-based compensation plans | 134,334 |
Shares outstanding, June 30, 2023 | 252,719,092 |
At-the-Market Offering Program - In December 2022, Alliant Energy filed a prospectus supplement under which it may sell up to $225 million of its common stock through an at-the-market offering program. As of June 30, 2023, Alliant Energy issued 1,221,775 shares of common stock through this program and received cash proceeds of $64 million, net of $1 million in commissions and fees. Alliant Energy also had commitments not recognized on its balance sheet at June 30, 2023 to sell 172,701 shares of common stock under sales transactions executed through this program in late June 2023. Subsequent to June 30, 2023, Alliant Energy issued shares to settle these transactions in exchange for net cash proceeds of $9 million. The proceeds from the issuances of common stock were used for general corporate purposes. 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 |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | Interest |  | Equity
Three Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2023 | $3 |  | $2,780 |  | $3,559 |  | ($1) |  | ($13) |  | $— |  | $6,328
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 160 |  |  |  |  |  |  |  | 160
Common stock dividends ($0.4525 per share) |  |  |  |  | (113) |  |  |  |  |  |  |  | (113)
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 70 |  |  |  |  |  |  |  |  |  | 70
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  | (1) |  |  |  | 3
Other comprehensive income, net of tax |  |  |  |  |  |  | 4 |  |  |  |  |  | 4
Ending balance, June 30, 2023 | $3 |  | $2,854 |  | $3,606 |  | $3 |  | ($14) |  | $— |  | $6,452
Three Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2022 | $3 |  | $2,750 |  | $3,336 |  | $— |  | ($12) |  | $— |  | $6,077
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 159 |  |  |  |  |  |  |  | 159
Common stock dividends ($0.4275 per share) |  |  |  |  | (108) |  |  |  |  |  |  |  | (108)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 3 |  |  |  |  |  |  |  |  |  | 3
Contributions from noncontrolling interest |  |  |  |  |  |  |  |  |  |  | 29 |  | 29
Ending balance, June 30, 2022 | $3 |  | $2,759 |  | $3,387 |  | $— |  | ($12) |  | $29 |  | $6,166
Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | Interest |  | Equity
Six Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $3 |  | $2,777 |  | $3,509 |  | $— |  | ($13) |  | $— |  | $6,276
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 323 |  |  |  |  |  |  |  | 323
Common stock dividends ($0.905 per share) |  |  |  |  | (226) |  |  |  |  |  |  |  | (226)
At-the-market offering program and Shareowner Direct Plan issuances |  |  | 76 |  |  |  |  |  |  |  |  |  | 76
Equity-based compensation plans and other |  |  | 1 |  |  |  |  |  | (1) |  |  |  | —
Other comprehensive income, net of tax |  |  |  |  |  |  | 3 |  |  |  |  |  | 3
Ending balance, June 30, 2023 | $3 |  | $2,854 |  | $3,606 |  | $3 |  | ($14) |  | $— |  | $6,452
Six Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2021 | $3 |  | $2,749 |  | $3,250 |  | $— |  | ($12) |  | $— |  | $5,990
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 351 |  |  |  |  |  |  |  | 351
Common stock dividends ($0.855 per share) |  |  |  |  | (215) |  |  |  |  |  |  |  | (215)
Shareowner Direct Plan issuances |  |  | 13 |  |  |  |  |  |  |  |  |  | 13
Equity-based compensation plans and other |  |  | (3) |  | 1 |  |  |  |  |  |  |  | (2)
Contributions from noncontrolling interest |  |  |  |  |  |  |  |  |  |  | 29 |  | 29
Ending balance, June 30, 2022 | $3 |  | $2,759 |  | $3,387 |  | $— |  | ($12) |  | $29 |  | $6,166
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2023 | $33 |  | $2,807 |  | $970 |  |  |  | $3,810
Net income |  |  |  |  | 89 |  |  |  | 89
Common stock dividends |  |  |  |  | (70) |  |  |  | (70)
Capital contributions from parent |  |  | 40 |  |  |  |  |  | 40
Ending balance, June 30, 2023 | $33 |  | $2,847 |  | $989 |  |  |  | $3,869
Three Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2022 | $33 |  | $2,807 |  | $935 |  |  |  | $3,775
Net income |  |  |  |  | 87 |  |  |  | 87
Common stock dividends |  |  |  |  | (80) |  |  |  | (80)
Ending balance, June 30, 2022 | $33 |  | $2,807 |  | $942 |  |  |  | $3,782
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Six Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $33 |  | $2,807 |  | $968 |  |  |  | $3,808
Net income |  |  |  |  | 161 |  |  |  | 161
Common stock dividends |  |  |  |  | (140) |  |  |  | (140)
Capital contributions from parent |  |  | 40 |  |  |  |  |  | 40
Ending balance, June 30, 2023 | $33 |  | $2,847 |  | $989 |  |  |  | $3,869
Six Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2021 | $33 |  | $2,807 |  | $929 |  |  |  | $3,769
Net income |  |  |  |  | 173 |  |  |  | 173
Common stock dividends |  |  |  |  | (160) |  |  |  | (160)
Ending balance, June 30, 2022 | $33 |  | $2,807 |  | $942 |  |  |  | $3,782
WPL | Total WPL Common Equity |  |  |  |
|  |  | Additional |  |  |  |  |  |
| Common |  | Paid-In |  | Retained |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Interest |  | Equity
Three Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2023 | $66 |  | $2,413 |  | $1,234 |  | $— |  | $3,713
Net income |  |  |  |  | 72 |  |  |  | 72
Common stock dividends |  |  |  |  | (46) |  |  |  | (46)
Ending balance, June 30, 2023 | $66 |  | $2,413 |  | $1,260 |  | $— |  | $3,739
Three Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, March 31, 2022 | $66 |  | $1,884 |  | $1,101 |  | $— |  | $3,051
Net income |  |  |  |  | 63 |  |  |  | 63
Common stock dividends |  |  |  |  | (44) |  |  |  | (44)
Capital contributions from parent |  |  | 85 |  |  |  |  |  | 85
Contributions from noncontrolling interest |  |  |  |  |  |  | 29 |  | 29
Other |  |  | (1) |  |  |  |  |  | (1)
Ending balance, June 30, 2022 | $66 |  | $1,968 |  | $1,120 |  | $29 |  | $3,183
WPL | Total WPL Common Equity |  |  |  |
|  |  | Additional |  |  |  |  |  |
| Common |  | Paid-In |  | Retained |  | Noncontrolling |  | Total
| Stock |  | Capital |  | Earnings |  | Interest |  | Equity
Six Months Ended June 30, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $66 |  | $2,233 |  | $1,192 |  | $— |  | $3,491
Net income |  |  |  |  | 160 |  |  |  | 160
Common stock dividends |  |  |  |  | (92) |  |  |  | (92)
Capital contributions from parent |  |  | 180 |  |  |  |  |  | 180
Ending balance, June 30, 2023 | $66 |  | $2,413 |  | $1,260 |  | $— |  | $3,739
Six Months Ended June 30, 2022 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2021 | $66 |  | $1,704 |  | $1,053 |  | $— |  | $2,823
Net income |  |  |  |  | 156 |  |  |  | 156
Common stock dividends |  |  |  |  | (89) |  |  |  | (89)
Capital contributions from parent |  |  | 265 |  |  |  |  |  | 265
Contributions from noncontrolling interest |  |  |  |  |  |  | 29 |  | 29
Other |  |  | (1) |  |  |  |  |  | (1)
Ending balance, June 30, 2022 | $66 |  | $1,968 |  | $1,120 |  | $29 |  | $3,183

X
- Definition Common Equity [Line Items] + References No definition available. + Details
Name: | lnt_CommonEquityLineItems
Namespace Prefix: | lnt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The entire disclosure for equity. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-13 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (h) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-13 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 14 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-14 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481062/946-235-50-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481062/946-235-50-2 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481004/946-505-50-6 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480237/815-40-50-6 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(e)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 505 -Name Accounting Standards Codification -Publisher FASB -URI https://asc.fasb.org//505/tableOfContent Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-13 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-13 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-13 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 14 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-14 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 14 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-14 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 16 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-16 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-18 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-18 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481112/505-10-50-18 + Details
Name: | us-gaap_StockholdersEquityNoteDisclosureTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=lnt_IplMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=lnt_WplMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |