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v3.22.2.2

Segments Of Business (Schedule Of Segments Of Business) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Segment Reporting Information [Line Items] |  |  |  |
Revenues | $ 1,135 | $ 1,024 | $ 3,147 | $ 2,742
Operating income (loss) | 309 | 289 | 769 | 663
Net income (loss) attributable to common shareowners | 227 | 256 | 579 | 571
Net income | 227 | 259 | 579 | 579
IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 640 | 599 | 1,696 | 1,543
Operating income (loss) | 171 | 180 | 389 | 394
Net income (loss) attributable to common shareowners | 154 | 157 | 327 | 322
Net income | 154 | 160 | 327 | 330
WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 472 | 403 | 1,381 | 1,139
Operating income (loss) | 131 | 100 | 357 | 245
Net income | 91 | 93 | 247 | 215
Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 1,039 | 939 | 2,624 | 2,357
Operating income (loss) | 304 | 290 | 680 | 601
Electric [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 596 | 555 | 1,438 | 1,343
Operating income (loss) | 174 | 186 | 353 | 365
Electric [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 443 | 384 | 1,186 | 1,014
Operating income (loss) | 130 | 104 | 327 | 236
Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 62 | 50 | 418 | 289
Operating income (loss) | (3) | (5) | 62 | 42
Gas [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 33 | 31 | 224 | 165
Operating income (loss) | (3) | (3) | 33 | 30
Gas [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 29 | 19 | 194 | 124
Operating income (loss) | 0 | (2) | 29 | 12
Other Utility [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 11 | 13 | 35 | 36
Operating income (loss) | 1 | (5) | 4 | (4)
Other Utility [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 11 | 13 | 34 | 35
Operating income (loss) | 0 | (3) | 3 | (1)
Other Utility [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 0 | 0 | 1 | 1
Operating income (loss) | 1 | (2) | 1 | (3)
Utility Business [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 1,112 | 1,002 | 3,077 | 2,682
Operating income (loss) | 302 | 280 | 746 | 639
Net income (loss) attributable to common shareowners | 245 | 250 | 574 | 537
ATC Holdings, Non-Utility, Parent and Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 23 | 22 | 70 | 60
Operating income (loss) | 7 | 9 | 23 | 24
Net income (loss) attributable to common shareowners | $ (18) | $ 6 | $ 5 | $ 34

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