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Property, Plant and Equipment (Property, Plant and Equipment) (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | $ 2,094 | $ 1,269
Total electric plant | 16,710 | 16,243
Gas plant in service | 1,636 | 1,563
Other plant in service | 621 | 534
Accumulated depreciation | (5,263) | (4,868)
Net plant | 13,704 | 13,472
Leased land for solar generation, net | 11 | 0
Construction work in progress | 778 | 405
Other, net | 7 | 7
Total utility | 14,500 | 13,884
Non-utility Generation, net | 75 | 79
Corporate Services and other, net | 412 | 373
Total non-utility and other | 487 | 452
Total property, plant and equipment | 14,987 | 14,336
Non-utility Generation, accumulated depreciation | 67 | 63
Corporate Services and other, accumulated depreciation | 245 | 210
Generation [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 7,539 | 8,222
Distribution [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 6,537 | 6,216
Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 540 | 536
IPL [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 487 | 459
Total electric plant | 9,424 | 9,171
Gas plant in service | 878 | 844
Other plant in service | 398 | 354
Accumulated depreciation | (2,897) | (2,671)
Net plant | 7,803 | 7,698
Construction work in progress | 174 | 185
Other, net | 6 | 6
Total utility | 7,983 | 7,889
Total property, plant and equipment | 7,983 | 7,889
IPL [Member] | Lansing [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 245 |
IPL [Member] | Generation [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 4,922 | 4,884
IPL [Member] | Distribution [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 3,652 | 3,470
IPL [Member] | Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 363 | 358
WPL [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 1,607 | 810
Total electric plant | 7,286 | 7,072
Gas plant in service | 758 | 719
Other plant in service | 223 | 180
Accumulated depreciation | (2,366) | (2,197)
Net plant | 5,901 | 5,774
Leased Sheboygan Falls Energy Facility, net | 21 | 27
Leased land for solar generation, net | 11 | 0
Construction work in progress | 604 | 220
Other, net | 1 | 1
Total utility | 6,538 | 6,022
Total property, plant and equipment | 6,538 | 6,022
Leased Sheboygan Falls Energy Facility, accumulated depreciation | 100 | 95
WPL [Member] | Edgewater Unit 5 [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 527 |
WPL [Member] | Columbia Units 1 And 2 [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant anticipated to be retired early | 460 |
WPL [Member] | Generation [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 2,617 | 3,338
WPL [Member] | Distribution [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | 2,885 | 2,746
WPL [Member] | Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Electric plant in service | $ 177 | $ 178

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