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v3.19.3.a.u2

Segment Information (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 USD ($) | Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Sep. 30, 2018 USD ($) | Jun. 30, 2018 USD ($) | Mar. 31, 2018 USD ($) | Dec. 31, 2019 USD ($) segment | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Segment information |  |  |  |  |  |  |  |  |  |  |
Number of reportable segments | segment |  |  |  |  |  |  |  |  | 6 |  |
Revenues | $ 1,947.5 | $ 1,608.0 | $ 1,590.2 | $ 2,377.4 | $ 2,076.8 | $ 1,643.7 | $ 1,672.5 | $ 2,286.5 | $ 7,523.1 | $ 7,679.5 | $ 7,648.5
Other operation and maintenance |  |  |  |  |  |  |  |  | 2,184.8 | 2,270.5 | 2,056.1
Depreciation and amortization |  |  |  |  |  |  |  |  | 926.3 | 845.8 | 798.6
Operating income (loss) | 363.1 | $ 310.9 | $ 314.6 | $ 542.8 | 289.8 | $ 302.7 | $ 330.8 | $ 545.1 | 1,531.4 | 1,468.4 | 1,776.1
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | 127.6 | 136.7 | 154.3
Interest expense |  |  |  |  |  |  |  |  | 501.5 | 445.1 | 415.7
Capital expenditures and asset acquisitions |  |  |  |  |  |  |  |  | 2,529.0 | 2,417.1 | 1,959.5
Total assets | 34,951.8 |  |  |  | 33,475.8 |  |  |  | 34,951.8 | 33,475.8 | 31,590.5
Wisconsin |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 5,647.1 | 5,794.7 |
Illinois |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 1,357.1 | 1,400.0 |
Other States |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 426.0 | 438.2 |
Electric transmission |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Other operation and maintenance |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Depreciation and amortization |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Operating income (loss) |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | 127.6 | 136.7 | 154.3
Interest expense |  |  |  |  |  |  |  |  | 13.1 | 0.3 | 0.0
Capital expenditures and asset acquisitions |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Total assets | 1,723.1 |  |  |  | 1,665.3 |  |  |  | $ 1,723.1 | 1,665.3 | 1,593.4
Non-Utility Energy Infrastructure |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Natural gas storage needs provided to Wisconsin utilities |  |  |  |  |  |  |  |  | 33.00% |  |
Revenues |  |  |  |  |  |  |  |  | $ 495.9 | 468.4 |
Other operation and maintenance |  |  |  |  |  |  |  |  | 19.7 | 12.6 | 7.3
Depreciation and amortization |  |  |  |  |  |  |  |  | 92.0 | 75.7 | 71.4
Operating income (loss) |  |  |  |  |  |  |  |  | 366.6 | 365.8 | 400.5
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Interest expense |  |  |  |  |  |  |  |  | 62.1 | 63.7 | 62.8
Capital expenditures and asset acquisitions |  |  |  |  |  |  |  |  | 389.9 | 260.6 | 35.4
Total assets | 3,654.1 |  |  |  | 3,227.2 |  |  |  | 3,654.1 | 3,227.2 | 2,992.8
Corporate and other |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 4.4 | 8.7 |
Other operation and maintenance |  |  |  |  |  |  |  |  | 14.0 | 1.8 | 1.4
Depreciation and amortization |  |  |  |  |  |  |  |  | 24.3 | 29.1 | 25.9
Operating income (loss) |  |  |  |  |  |  |  |  | (34.4) | (22.2) | (13.9)
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Interest expense |  |  |  |  |  |  |  |  | 140.9 | 125.8 | 107.3
Capital expenditures and asset acquisitions |  |  |  |  |  |  |  |  | 26.5 | 39.7 | 152.1
Total assets | 814.0 |  |  |  | 959.6 |  |  |  | 814.0 | 959.6 | 953.6
Reconciling eliminations |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Other operation and maintenance |  |  |  |  |  |  |  |  | 0.2 | (393.3) | (441.1)
Depreciation and amortization |  |  |  |  |  |  |  |  | (15.8) | 0.0 | 0.0
Operating income (loss) |  |  |  |  |  |  |  |  | (347.6) | 0.0 | 0.0
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Interest expense |  |  |  |  |  |  |  |  | (354.1) | (5.3) | (1.8)
Capital expenditures and asset acquisitions |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Total assets | (3,344.5) |  |  |  | (3,414.5) |  |  |  | (3,344.5) | (3,414.5) | (3,398.9)
Reconciling eliminations | WE |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Total assets | $ 1,896.7 |  |  |  | 1,968.5 |  |  |  | $ 1,896.7 | 1,968.5 | 2,038.1
ATC |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership interest (as a percent) | 60.00% |  |  |  |  |  |  |  | 60.00% |  |
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | $ 132.8 | 139.6 | 166.0
ATC | Electric transmission |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership interest (as a percent) | 60.00% |  |  |  |  |  |  |  | 60.00% |  |
ATC HoldCo |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership interest (as a percent) | 75.00% |  |  |  |  |  |  |  | 75.00% |  |
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | $ (5.2) | (2.9) | (11.7)
ATC HoldCo | Electric transmission |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership interest (as a percent) | 75.00% |  |  |  |  |  |  |  | 75.00% |  |
Bishop Hill III Wind Energy Center | Non-Utility Energy Infrastructure |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
WEC's ownership interest in Bishop Hill III Wind Energy Center | 90.00% |  |  |  |  |  |  |  | 90.00% |  |
Coyote Ridge | Non-Utility Energy Infrastructure |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
WEC's ownership interest in Coyote Ridge Wind, LLC | 80.00% |  |  |  |  |  |  |  | 80.00% |  |
Upstream | Non-Utility Energy Infrastructure |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
WEC's ownership interest in Upstream Wind Energy Center | 80.00% |  |  |  |  |  |  |  | 80.00% |  |
Public Utilities |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Other operation and maintenance |  |  |  |  |  |  |  |  | $ 2,150.9 | 2,649.4 | 2,488.5
Depreciation and amortization |  |  |  |  |  |  |  |  | 825.8 | 741.0 | 701.3
Operating income (loss) |  |  |  |  |  |  |  |  | 1,546.8 | 1,124.8 | 1,389.5
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Interest expense |  |  |  |  |  |  |  |  | 639.5 | 260.6 | 247.4
Capital expenditures and asset acquisitions |  |  |  |  |  |  |  |  | 2,112.6 | 2,116.8 | 1,772.0
Total assets | $ 32,105.1 |  |  |  | 31,038.2 |  |  |  | 32,105.1 | 31,038.2 | 29,449.6
Public Utilities | Wisconsin |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Other operation and maintenance |  |  |  |  |  |  |  |  | 1,591.3 | 2,076.1 | 1,923.2
Depreciation and amortization |  |  |  |  |  |  |  |  | 617.0 | 546.6 | 523.9
Operating income (loss) |  |  |  |  |  |  |  |  | 1,189.6 | 800.2 | 1,055.2
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Interest expense |  |  |  |  |  |  |  |  | 572.0 | 200.7 | 193.7
Capital expenditures and asset acquisitions |  |  |  |  |  |  |  |  | 1,378.6 | 1,466.1 | 1,152.3
Total assets | 23,934.8 |  |  |  | 23,407.0 |  |  |  | 23,934.8 | 23,407.0 | 22,237.1
Public Utilities | Illinois |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Other operation and maintenance |  |  |  |  |  |  |  |  | 461.1 | 472.3 | 464.2
Depreciation and amortization |  |  |  |  |  |  |  |  | 181.3 | 170.3 | 152.6
Operating income (loss) |  |  |  |  |  |  |  |  | 291.9 | 255.8 | 279.9
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Interest expense |  |  |  |  |  |  |  |  | 59.0 | 51.2 | 45.0
Capital expenditures and asset acquisitions |  |  |  |  |  |  |  |  | 624.9 | 547.1 | 545.2
Total assets | 6,932.5 |  |  |  | 6,483.3 |  |  |  | 6,932.5 | 6,483.3 | 6,144.7
Public Utilities | Other States |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Other operation and maintenance |  |  |  |  |  |  |  |  | 98.5 | 101.0 | 101.1
Depreciation and amortization |  |  |  |  |  |  |  |  | 27.5 | 24.1 | 24.8
Operating income (loss) |  |  |  |  |  |  |  |  | 65.3 | 68.8 | 54.4
Equity in earnings of transmission affiliates |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Interest expense |  |  |  |  |  |  |  |  | 8.5 | 8.7 | 8.7
Capital expenditures and asset acquisitions |  |  |  |  |  |  |  |  | 109.1 | 103.6 | 74.5
Total assets | $ 1,237.8 |  |  |  | $ 1,147.9 |  |  |  | 1,237.8 | 1,147.9 | 1,067.8
External Revenues | Electric transmission |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
External Revenues | Non-Utility Energy Infrastructure |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 88.5 | 37.9 | 38.9
External Revenues | Corporate and other |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 4.4 | 8.7 | 13.7
External Revenues | Reconciling eliminations |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
External Revenues | Public Utilities |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 7,430.2 | 7,632.9 | 7,595.9
External Revenues | Public Utilities | Wisconsin |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 5,647.1 | 5,794.7 | 5,829.2
External Revenues | Public Utilities | Illinois |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 1,357.1 | 1,400.0 | 1,355.5
External Revenues | Public Utilities | Other States |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 426.0 | 438.2 | 411.2
Intersegment Transactions |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Intersegment Transactions | Electric transmission |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Intersegment Transactions | Non-Utility Energy Infrastructure |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 407.4 | 430.5 | 446.3
Intersegment Transactions | Corporate and other |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Intersegment Transactions | Reconciling eliminations |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | (407.4) | (430.5) | (446.3)
Intersegment Transactions | Public Utilities |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Intersegment Transactions | Public Utilities | Wisconsin |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Intersegment Transactions | Public Utilities | Illinois |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0
Intersegment Transactions | Public Utilities | Other States |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | $ 0.0 | $ 0.0 | $ 0.0

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