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v3.22.2

Segments Of Business (Schedule Of Segments Of Business) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Segment Reporting Information [Line Items] |  |  |  |
Revenues | $ 943 | $ 817 | $ 2,012 | $ 1,718
Operating income (loss) | 212 | 176 | 460 | 374
Net income attributable to common shareowners | 159 | 144 | 351 | 315
Net income | 159 | 146 | 351 | 320
IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 506 | 455 | 1,056 | 944
Operating income (loss) | 109 | 111 | 218 | 214
Net income attributable to common shareowners | 87 | 86 | 173 | 165
Net income | 87 | 88 | 173 | 170
WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 413 | 341 | 909 | 736
Operating income (loss) | 95 | 55 | 227 | 145
Net income | 63 | 38 | 156 | 122
Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 812 | 717 | 1,586 | 1,418
Operating income (loss) | 195 | 164 | 376 | 311
Electric [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 442 | 402 | 843 | 788
Operating income (loss) | 104 | 107 | 179 | 179
Electric [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 370 | 315 | 743 | 630
Operating income (loss) | 91 | 57 | 197 | 132
Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 94 | 69 | 356 | 239
Operating income (loss) | 8 | 3 | 65 | 47
Gas [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 52 | 43 | 191 | 134
Operating income (loss) | 4 | 3 | 36 | 33
Gas [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 42 | 26 | 165 | 105
Operating income (loss) | 4 | 0 | 29 | 14
Other Utility [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 13 | 10 | 23 | 23
Operating income (loss) | 1 | (1) | 4 | 1
Other Utility [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 12 | 10 | 22 | 22
Operating income (loss) | 1 | 1 | 3 | 2
Other Utility [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 1 | 0 | 1 | 1
Operating income (loss) | 0 | (2) | 1 | (1)
Utility Business [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 919 | 796 | 1,965 | 1,680
Operating income (loss) | 204 | 166 | 445 | 359
Net income attributable to common shareowners | 150 | 124 | 329 | 287
ATC Holdings, Non-Utility, Parent and Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 24 | 21 | 47 | 38
Operating income (loss) | 8 | 10 | 15 | 15
Net income attributable to common shareowners | $ 9 | $ 20 | $ 22 | $ 28

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