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Property, Plant and Equipment (Property, Plant and Equipment) (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | $ 2,103 | $ 2,094
Total electric plant | 17,618 | 16,710
Gas plant in service | 1,705 | 1,636
Other plant in service | 624 | 621
Accumulated depreciation | (5,690) | (5,263)
Net plant | 14,257 | 13,704
Leased land for solar generation, net | 133 | 11
Construction work in progress | 1,357 | 778
Other, net | 6 | 7
Total utility | 15,753 | 14,500
Non-utility Generation, net | 71 | 75
Corporate Services and other, net | 423 | 412
Total non-utility and other | 494 | 487
Total property, plant and equipment | 16,247 | 14,987
Non-utility Generation, accumulated depreciation | 71 | 67
Corporate Services and other, accumulated depreciation | 269 | 245
Generation [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 8,060 | 7,539
Distribution [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 6,912 | 6,537
Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 543 | 540
IPL [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 491 | 487
Total electric plant | 9,683 | 9,424
Gas plant in service | 910 | 878
Other plant in service | 402 | 398
Accumulated depreciation | (3,149) | (2,897)
Net plant | 7,846 | 7,803
Leased land for solar generation, net | 0 | 0
Construction work in progress | 194 | 174
Other, net | 6 | 6
Total utility | 8,046 | 7,983
Total property, plant and equipment | 8,046 | 7,983
IPL [Member] | Lansing [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 233 |
IPL [Member] | Generation [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 4,962 | 4,922
IPL [Member] | Distribution [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 3,876 | 3,652
IPL [Member] | Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 354 | 363
WPL [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 1,612 | 1,607
Total electric plant | 7,935 | 7,286
Gas plant in service | 795 | 758
Other plant in service | 222 | 223
Accumulated depreciation | (2,541) | (2,366)
Net plant | 6,411 | 5,901
Leased Sheboygan Falls Energy Facility, net | 15 | 21
Leased land for solar generation, net | 133 | 11
Construction work in progress | 1,163 | 604
Other, net | 0 | 1
Total utility | 7,722 | 6,538
Total property, plant and equipment | 7,722 | 6,538
Leased Sheboygan Falls Energy Facility, accumulated depreciation | 106 | 100
WPL [Member] | Edgewater Unit 5 [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 511 |
WPL [Member] | Columbia Units 1-2 [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 440 |
WPL [Member] | Generation [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 3,098 | 2,617
WPL [Member] | Distribution [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 3,036 | 2,885
WPL [Member] | Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | $ 189 | $ 177

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