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Segments Of Business (Schedule Of Segment Of Business) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Segment Reporting Information [Line Items] |  |  |
Revenues | $ 4,205 | $ 3,669 | $ 3,416
Depreciation and amortization | 671 | 657 | 615
Operating income (loss) | 928 | 795 | 740
Interest expense | 325 | 277 | 275
Equity income from unconsolidated investments, net | (51) | (62) | (61)
Income tax expense (benefit) | 22 | (74) | (57)
Net income attributable to common shareowners | 686 | 659 | 614
Total assets | 20,163 | 18,553 | 17,710
Investments in equity method subsidiaries | 542 | 508 | 476
Construction and acquisition expenditures | 1,484 | 1,169 | 1,366
IPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 2,256 | 2,063 | 1,947
Operating income (loss) | 453 | 460 | 410
Interest expense | 148 | 139 | 139
Income tax expense (benefit) | (50) | (36) | (47)
Net income attributable to common shareowners | 360 | 350 | 324
Total assets | 10,075 | 9,996 |
WPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 1,856 | 1,523 | 1,395
Operating income (loss) | 452 | 308 | 306
Interest expense | 121 | 105 | 104
Income tax expense (benefit) | 66 | (51) | (19)
Total assets | 8,987 | 7,518 |
Electric [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 3,421 | 3,081 | 2,920
Depreciation and amortization | 601 | 591 | 556
Operating income (loss) | 805 | 716 | 643
Equity income from unconsolidated investments, net | (1) | (2) | (2)
Total assets | 16,571 | 14,924 | 14,358
Investments in equity method subsidiaries | 20 | 17 | 11
Construction and acquisition expenditures | 1,318 | 980 | 1,109
Electric [Member] | IPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 1,859 | 1,752 | 1,695
Depreciation and amortization | 342 | 338 | 321
Operating income (loss) | 397 | 420 | 358
Total assets | 8,686 | 8,602 | 8,518
Construction and acquisition expenditures | 336 | 342 | 626
Electric [Member] | WPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 1,562 | 1,329 | 1,225
Depreciation and amortization | 259 | 253 | 235
Operating income (loss) | 408 | 296 | 285
Total assets | 7,885 | 6,322 | 5,840
Construction and acquisition expenditures | 982 | 638 | 483
Gas [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 642 | 456 | 373
Depreciation and amortization | 56 | 54 | 49
Operating income (loss) | 97 | 63 | 74
Equity income from unconsolidated investments, net | 0 | 0 | 0
Total assets | 1,631 | 1,487 | 1,413
Investments in equity method subsidiaries | 0 | 0 | 0
Construction and acquisition expenditures | 74 | 90 | 182
Gas [Member] | IPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 351 | 265 | 208
Depreciation and amortization | 32 | 31 | 30
Operating income (loss) | 53 | 43 | 50
Total assets | 872 | 819 | 766
Construction and acquisition expenditures | 36 | 42 | 59
Gas [Member] | WPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 291 | 191 | 165
Depreciation and amortization | 24 | 23 | 19
Operating income (loss) | 44 | 20 | 24
Total assets | 759 | 668 | 647
Construction and acquisition expenditures | 38 | 48 | 123
Other Utility [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 49 | 49 | 49
Depreciation and amortization | 7 | 6 | 5
Operating income (loss) | 3 | (11) | (1)
Equity income from unconsolidated investments, net | 0 | 0 | 0
Total assets | 860 | 1,103 | 990
Investments in equity method subsidiaries | 0 | 0 | 0
Construction and acquisition expenditures | 0 | 0 | 2
Other Utility [Member] | IPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 46 | 46 | 44
Depreciation and amortization | 7 | 6 | 5
Operating income (loss) | 3 | (3) | 2
Total assets | 517 | 575 | 565
Construction and acquisition expenditures | 0 | 0 | 2
Other Utility [Member] | WPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 3 | 3 | 5
Depreciation and amortization | 0 | 0 | 0
Operating income (loss) | 0 | (8) | (3)
Total assets | 343 | 528 | 425
Construction and acquisition expenditures | 0 | 0 | 0
Utility Business [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 4,112 | 3,586 | 3,342
Depreciation and amortization | 664 | 651 | 610
Operating income (loss) | 905 | 768 | 716
Interest expense | 269 | 244 | 243
Equity income from unconsolidated investments, net | (1) | (2) | (2)
Income tax expense (benefit) | 16 | (87) | (66)
Net income attributable to common shareowners | 675 | 618 | 573
Total assets | 19,062 | 17,514 | 16,761
Investments in equity method subsidiaries | 20 | 17 | 11
Construction and acquisition expenditures | 1,392 | 1,070 | 1,293
Utility Business [Member] | IPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 2,256 | 2,063 | 1,947
Depreciation and amortization | 381 | 375 | 356
Operating income (loss) | 453 | 460 | 410
Interest expense | 148 | 139 | 139
Income tax expense (benefit) | (50) | (36) | (47)
Net income attributable to common shareowners | 360 | 350 | 324
Total assets | 10,075 | 9,996 | 9,849
Construction and acquisition expenditures | 372 | 384 | 687
Utility Business [Member] | WPL [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 1,856 | 1,523 | 1,395
Depreciation and amortization | 283 | 276 | 254
Operating income (loss) | 452 | 308 | 306
Interest expense | 121 | 105 | 104
Income tax expense (benefit) | 66 | (51) | (19)
Net income attributable to common shareowners | 315 | 268 | 249
Total assets | 8,987 | 7,518 | 6,912
Construction and acquisition expenditures | 1,020 | 686 | 606
Non-Utility [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 93 | 83 | 74
Depreciation and amortization | 7 | 6 | 5
Operating income (loss) | 23 | 27 | 24
Interest expense | 56 | 33 | 32
Equity income from unconsolidated investments, net | (50) | (60) | (59)
Income tax expense (benefit) | 6 | 13 | 9
Net income attributable to common shareowners | 11 | 41 | 41
Total assets | 1,101 | 1,039 | 949
Investments in equity method subsidiaries | 522 | 491 | 465
Construction and acquisition expenditures | $ 92 | $ 99 | $ 73

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