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Segments Of Business (Schedule Of Segments Of Business) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Segment Reporting Information [Line Items] |  |  |  |
Revenues | $ 894 | $ 912 | $ 1,925 | $ 1,990
Operating income (loss) | 130 | 217 | 352 | 439
Net income (loss) attributable to common shareowners | 87 | 160 | 245 | 323
Net income |  |  | 245 | 323
IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 453 | 487 | 966 | 1,037
Operating income (loss) | 16 | 110 | 101 | 206
Net income (loss) attributable to common shareowners | 18 | 89 | 81 | 161
Net income | 18 | 89 | 81 | 161
WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 415 | 402 | 911 | 908
Operating income (loss) | 100 | 99 | 231 | 220
Net income (loss) attributable to common shareowners | 64 | 72 | 156 | 160
Net income | 64 | 72 | 156 | 160
Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 789 | 799 | 1,580 | 1,567
Operating income (loss) | 131 | 200 | 295 | 363
Electric [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 404 | 431 | 795 | 819
Operating income (loss) | 34 | 105 | 91 | 171
Electric [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 385 | 368 | 785 | 748
Operating income (loss) | 97 | 95 | 204 | 192
Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 69 | 77 | 273 | 353
Operating income (loss) | 1 | 2 | 48 | 52
Gas [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 40 | 44 | 148 | 194
Operating income (loss) | (1) | 0 | 21 | 27
Gas [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 29 | 33 | 125 | 159
Operating income (loss) | 2 | 2 | 27 | 25
Other Utility [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 10 | 13 | 24 | 25
Operating income (loss) | (16) | 7 | (11) | 11
Other Utility [Member] | IPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 9 | 12 | 23 | 24
Operating income (loss) | (17) | 5 | (11) | 8
Other Utility [Member] | WPL [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 1 | 1 | 1 | 1
Operating income (loss) | 1 | 2 | 0 | 3
Non-utility and Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 26 | 23 | 48 | 45
Operating income (loss) | 14 | 8 | 20 | 13
Net income (loss) attributable to common shareowners | 5 | (1) | 8 | 2
Utility Business [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 868 | 889 | 1,877 | 1,945
Operating income (loss) | 116 | 209 | 332 | 426
Net income (loss) attributable to common shareowners | $ 82 | $ 161 | $ 237 | $ 321

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