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Property, Plant and Equipment (Property, Plant and Equipment) (Details) $ in Millions | Dec. 31, 2023 USD ($) MW | Dec. 31, 2022 USD ($)
--- | --- | ---
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | $ 1,629 | $ 2,103
Total electric plant | 18,690 | 17,618
Gas plant in service | 1,791 | 1,705
Other plant in service | 653 | 624
Accumulated depreciation | (5,924) | (5,690)
Net plant | 15,210 | 14,257
Leased land for solar generation, net | 172 | 133
Construction work in progress | 1,245 | 1,357
Other, net | 7 | 6
Total utility | 16,634 | 15,753
Non-utility Generation, net | 68 | 71
Corporate Services and other, net | 455 | 423
Total non-utility and other | 523 | 494
Total property, plant and equipment | 17,157 | 16,247
Non-utility Generation, accumulated depreciation | 75 | 71
Corporate Services and other, accumulated depreciation | 275 | 269
Generation [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 9,180 | 8,060
Distribution [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 7,314 | 6,912
Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 567 | 543
IPL [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 0 | 491
Total electric plant | 9,472 | 9,683
Gas plant in service | 951 | 910
Other plant in service | 411 | 402
Accumulated depreciation | (3,180) | (3,149)
Net plant | 7,654 | 7,846
Leased land for solar generation, net | 33 | 0
Construction work in progress | 605 | 194
Other, net | 6 | 6
Total utility | 8,298 | 8,046
Total property, plant and equipment | $ 8,298 | 8,046
Electric capacity of solar project | MW | 400 |
Construction project cost target | $ 1,650 |
Construction project cost target exceedance, percentage | 10.00% |
IPL [Member] | Generation [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | $ 5,025 | 4,962
IPL [Member] | Distribution [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 4,091 | 3,876
IPL [Member] | Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 356 | 354
WPL [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 1,629 | 1,612
Total electric plant | 9,218 | 7,935
Gas plant in service | 840 | 795
Other plant in service | 242 | 222
Accumulated depreciation | (2,744) | (2,541)
Net plant | 7,556 | 6,411
Leased Sheboygan Falls Energy Facility, net | 79 | 15
Leased land for solar generation, net | 139 | 133
Construction work in progress | 640 | 1,163
Other, net | 1 | 0
Total utility | 8,415 | 7,722
Total property, plant and equipment | $ 8,415 | 7,722
Electric capacity of solar project | MW | 1,100 |
Construction project cost target exceedance | $ 180 |
Leased Sheboygan Falls Energy Facility, accumulated depreciation | 112 | 106
WPL [Member] | Edgewater Unit 5 [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 504 |
WPL [Member] | Columbia Units 1-2 [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 428 |
WPL [Member] | Generation [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 4,155 | 3,098
WPL [Member] | Distribution [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 3,223 | 3,036
WPL [Member] | Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | $ 211 | $ 189

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