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v3.23.2

Segments Of Business (Schedule Of Segments Of Business) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Segment Reporting Information [Line Items] |  |  |  |
Revenues | $ 912 | $ 943 | $ 1,990 | $ 2,012
Operating income | 217 | 212 | 439 | 460
Net income (loss) attributable to common shareowners | 160 | 159 | 323 | 351
Net income |  |  | 323 | 351
IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 487 | 506 | 1,037 | 1,056
Operating income | 110 | 109 | 206 | 218
Net income | 89 | 87 | 161 | 173
WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 402 | 413 | 908 | 909
Operating income | 99 | 95 | 220 | 227
Net income | 72 | 63 | 160 | 156
Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 799 | 812 | 1,567 | 1,586
Operating income | 200 | 195 | 363 | 376
Electric [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 431 | 442 | 819 | 843
Operating income | 105 | 104 | 171 | 179
Electric [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 368 | 370 | 748 | 743
Operating income | 95 | 91 | 192 | 197
Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 77 | 94 | 353 | 356
Operating income | 2 | 8 | 52 | 65
Gas [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 44 | 52 | 194 | 191
Operating income | 0 | 4 | 27 | 36
Gas [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 33 | 42 | 159 | 165
Operating income | 2 | 4 | 25 | 29
Other Utility [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 13 | 13 | 25 | 23
Operating income | 7 | 1 | 11 | 4
Other Utility [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 12 | 12 | 24 | 22
Operating income | 5 | 1 | 8 | 3
Other Utility [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 1 | 1 | 1 | 1
Operating income | 2 | 0 | 3 | 1
Utility Business [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 889 | 919 | 1,945 | 1,965
Operating income | 209 | 204 | 426 | 445
Net income (loss) attributable to common shareowners | 161 | 150 | 321 | 329
ATC Holdings, Non-Utility, Parent and Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 23 | 24 | 45 | 47
Operating income | 8 | 8 | 13 | 15
Net income (loss) attributable to common shareowners | $ (1) | $ 9 | $ 2 | $ 22

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