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v3.20.2

Common Equity (Changes in Shareowners' Equity) (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance |  |  | $ 5,205 |
Beginning balance | $ 5,748 | $ 4,900 | 5,405 | $ 4,786
Net income attributable to common shareowners | 246 | 226 | 550 | 446
Net income | 249 | 229 | 558 | 454
Common stock dividends | (94) | (85) | (281) | (253)
Equity forward settlements and Shareowner Direct Plan issuances | 6 | 125 | 241 | 185
Equity-based compensation plans and other | 3 | 3 | 5 | 6
Adoption of new accounting standard, net of tax |  |  | (9) |
Other comprehensive loss, net of tax |  |  | (2) | (1)
Ending balance | 5,709 |  | 5,709 |
Ending balance | $ 5,909 | $ 5,169 | $ 5,909 | $ 5,169
Common stock dividends (in dollars per share) | $ 0.38 | $ 0.355 | $ 1.14 | $ 1.065
Common Stock [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | $ 2 | $ 2 | $ 2 | $ 2
Ending balance | 2 | 2 | 2 | 2
Additional Paid-in Capital [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 2,683 | 2,109 | 2,446 | 2,046
Equity forward settlements and Shareowner Direct Plan issuances | 6 | 125 | 241 | 185
Equity-based compensation plans and other | 4 | 3 | 6 | 6
Ending balance | 2,693 | 2,237 | 2,693 | 2,237
Retained Earnings [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 2,874 | 2,598 | 2,766 | 2,546
Net income attributable to common shareowners | 246 | 226 | 550 | 446
Common stock dividends | (94) | (85) | (281) | (253)
Ending balance | 3,026 | 2,739 | 3,026 | 2,739
Accumulated Other Comprehensive Income (Loss) [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | (1) | 1 | 1 | 2
Other comprehensive loss, net of tax |  |  | (2) | (1)
Ending balance | (1) | 1 | (1) | 1
Shares in Deferred Compensation Trust [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | (10) | (10) | (10) | (10)
Equity-based compensation plans and other | (1) |  | (1) |
Ending balance | (11) | (10) | (11) | (10)
Cumulative Preferred Stock [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 200 | 200 | 200 | 200
Ending balance | 200 | 200 | 200 | 200
IPL [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance |  |  | 3,272 |
Beginning balance | 3,671 | 3,345 | 3,472 | 3,231
Net income attributable to common shareowners | 148 | 141 | 290 | 239
Net income | 151 | 144 | 298 | 247
Common stock dividends | (59) | (42) | (177) | (126)
Capital contributions from parent | 170 |  | 345 | 100
Ending balance | 3,730 |  | 3,730 |
Ending balance | 3,930 | 3,444 | 3,930 | 3,444
IPL [Member] | Common Stock [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 33 | 33 | 33 | 33
Ending balance | 33 | 33 | 33 | 33
IPL [Member] | Additional Paid-in Capital [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 2,523 | 2,323 | 2,348 | 2,223
Capital contributions from parent | 170 |  | 345 | 100
Ending balance | 2,693 | 2,323 | 2,693 | 2,323
IPL [Member] | Retained Earnings [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 915 | 789 | 891 | 775
Net income attributable to common shareowners | 148 | 141 | 290 | 239
Common stock dividends | (59) | (42) | (177) | (126)
Ending balance | 1,004 | 888 | 1,004 | 888
IPL [Member] | Cumulative Preferred Stock [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 200 | 200 | 200 | 200
Ending balance | 200 | 200 | 200 | 200
WPL [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance |  |  | 2,364 |
Beginning balance | 2,452 | 2,185 | 2,364 | 2,150
Net income | 73 | 76 | 220 | 183
Common stock dividends | (43) | (36) | (127) | (108)
Capital contributions from parent |  | 100 | 25 | 100
Ending balance | 2,482 |  | 2,482 |
Ending balance | 2,482 | 2,325 | 2,482 | 2,325
WPL [Member] | Common Stock [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 66 | 66 | 66 | 66
Ending balance | 66 | 66 | 66 | 66
WPL [Member] | Additional Paid-in Capital [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 1,459 | 1,309 | 1,434 | 1,309
Capital contributions from parent |  | 100 | 25 | 100
Ending balance | 1,459 | 1,409 | 1,459 | 1,409
WPL [Member] | Retained Earnings [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Beginning balance | 927 | 810 | 864 | 775
Net income | 73 | 76 | 220 | 183
Common stock dividends | (43) | (36) | (127) | (108)
Ending balance | $ 957 | $ 850 | 957 | $ 850
Credit Losses ASU [Member] | Retained Earnings [Member] |  |  |  |
Changes in Shareowners' Equity Roll Forward [Line Items] |  |  |  |
Adoption of new accounting standard, net of tax |  |  | $ (9) |

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