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v3.6.0.2

Segment Information (Details) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2016 USD ($) | Sep. 30, 2016 USD ($) | Jun. 30, 2016 USD ($) | Mar. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Sep. 30, 2015 USD ($) | Jun. 30, 2015 USD ($) | Mar. 31, 2015 USD ($) | Dec. 31, 2016 USD ($) segment | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Jun. 29, 2015
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Document Period End Date |  |  |  |  |  |  |  |  | Dec. 31, 2016 |  |  |
Number of reportable segments | segment |  |  |  |  |  |  |  |  | 6 |  |  |
Revenues | $ 1,963.0 | $ 1,712.5 | $ 1,602.0 | $ 2,194.8 | $ 1,848.3 | $ 1,698.7 | $ 991.2 | $ 1,387.9 | $ 7,472.3 | $ 5,926.1 | $ 4,997.1 |
Other operation and maintenance |  |  |  |  |  |  |  |  | 2,185.5 | 1,709.3 | 1,112.4 |
Depreciation and amortization |  |  |  |  |  |  |  |  | 762.6 | 561.8 | 391.4 |
Operating income (loss) | 361.7 | $ 399.0 | $ 332.1 | $ 589.3 | 380.2 | $ 345.7 | $ 165.8 | $ 358.8 | 1,682.1 | 1,250.5 | 1,112.1 |
Equity in earnings of transmission affiliate |  |  |  |  |  |  |  |  | 146.5 | 96.1 | 66.0 |
Interest expense |  |  |  |  |  |  |  |  | 402.7 | 331.4 | 240.3 |
Capital expenditures |  |  |  |  |  |  |  |  | 1,423.7 | 1,266.2 | 761.2 |
Total assets | 30,123.2 |  |  |  | 29,355.2 |  |  |  | 30,123.2 | 29,355.2 | 14,905.0 |
Intersegment revenues |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
We Power |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 24.9 | 40.0 | 55.7 |
Other operation and maintenance |  |  |  |  |  |  |  |  | 4.3 | 4.3 | 4.4 |
Depreciation and amortization |  |  |  |  |  |  |  |  | 68.3 | 67.5 | 66.7 |
Operating income (loss) |  |  |  |  |  |  |  |  | 375.6 | 373.4 | 368.0 |
Equity in earnings of transmission affiliate |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Interest expense |  |  |  |  |  |  |  |  | 62.1 | 63.4 | 64.6 |
Capital expenditures |  |  |  |  |  |  |  |  | 62.3 | 53.4 | 41.0 |
Total assets | 2,777.1 |  |  |  | 2,779.0 |  |  |  | 2,777.1 | 2,779.0 | 2,789.9 |
We Power | Intersegment revenues |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 423.3 | 405.2 | 383.4 |
Corporate and other |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 23.3 | 47.3 | 9.3 |
Other operation and maintenance |  |  |  |  |  |  |  |  | (15.8) | 103.7 | 33.0 |
Depreciation and amortization |  |  |  |  |  |  |  |  | 42.6 | 12.4 | 1.5 |
Operating income (loss) |  |  |  |  |  |  |  |  | (10.0) | (91.2) | (26.1) |
Equity in earnings of transmission affiliate |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Interest expense |  |  |  |  |  |  |  |  | 120.9 | 91.0 | 48.8 |
Capital expenditures |  |  |  |  |  |  |  |  | 97.8 | 33.4 | 5.2 |
Total assets | 778.0 |  |  |  | 1,132.5 |  |  |  | 778.0 | 1,132.5 | 253.3 |
Corporate and other | Intersegment revenues |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Reconciling eliminations |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Other operation and maintenance |  |  |  |  |  |  |  |  | (423.6) | (409.3) | (387.7) |
Depreciation and amortization |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Operating income (loss) |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Equity in earnings of transmission affiliate |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Interest expense |  |  |  |  |  |  |  |  | (8.6) | (5.1) | (0.7) |
Capital expenditures |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Total assets | (3,349.2) |  |  |  | (3,431.7) |  |  |  | (3,349.2) | (3,431.7) | (2,966.1) |
Reconciling eliminations | WE |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Total assets | 2,029.5 |  |  |  | 2,105.3 |  |  |  | 2,029.5 | 2,105.3 | 2,172.9 |
Reconciling eliminations | Intersegment revenues |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | (423.6) | (410.2) | (392.6) |
Regulated operations |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 7,424.1 | 5,838.8 | 4,932.1 |
Other operation and maintenance |  |  |  |  |  |  |  |  | 2,620.6 | 2,010.6 | 1,462.7 |
Depreciation and amortization |  |  |  |  |  |  |  |  | 651.7 | 481.9 | 323.2 |
Operating income (loss) |  |  |  |  |  |  |  |  | 1,316.5 | 968.3 | 770.2 |
Equity in earnings of transmission affiliate |  |  |  |  |  |  |  |  | 146.5 | 96.1 | 66.0 |
Interest expense |  |  |  |  |  |  |  |  | 228.3 | 182.1 | 127.6 |
Capital expenditures |  |  |  |  |  |  |  |  | 1,263.6 | 1,179.4 | 715.0 |
Total assets | 29,917.3 |  |  |  | 28,875.4 |  |  |  | 29,917.3 | 28,875.4 | 14,827.9 |
Regulated operations | Intersegment revenues |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.3 | 5.0 | 9.2 |
Regulated operations | Wisconsin |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 5,805.4 | 5,186.1 | 4,932.1 |
Other operation and maintenance |  |  |  |  |  |  |  |  | 2,025.4 | 1,741.0 | 1,462.7 |
Depreciation and amortization |  |  |  |  |  |  |  |  | 496.6 | 408.6 | 323.2 |
Operating income (loss) |  |  |  |  |  |  |  |  | 1,027.0 | 884.2 | 770.2 |
Equity in earnings of transmission affiliate |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Interest expense |  |  |  |  |  |  |  |  | 180.9 | 157.1 | 127.6 |
Capital expenditures |  |  |  |  |  |  |  |  | 910.9 | 950.3 | 715.0 |
Total assets | 21,730.7 |  |  |  | 21,113.5 |  |  |  | 21,730.7 | 21,113.5 | 14,403.8 |
Regulated operations | Wisconsin | Intersegment revenues |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.3 | 5.0 | 9.2 |
Regulated operations | Illinois |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 1,242.2 | 503.4 | 0.0 |
Other operation and maintenance |  |  |  |  |  |  |  |  | 485.1 | 219.6 | 0.0 |
Depreciation and amortization |  |  |  |  |  |  |  |  | 134.0 | 63.3 | 0.0 |
Operating income (loss) |  |  |  |  |  |  |  |  | 239.6 | 78.1 | 0.0 |
Equity in earnings of transmission affiliate |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Interest expense |  |  |  |  |  |  |  |  | 38.9 | 19.9 | 0.0 |
Capital expenditures |  |  |  |  |  |  |  |  | 293.2 | 194.4 | 0.0 |
Total assets | 5,714.6 |  |  |  | 5,462.9 |  |  |  | 5,714.6 | 5,462.9 | 0.0 |
Regulated operations | Illinois | Intersegment revenues |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Regulated operations | Other States |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 376.5 | 149.3 | 0.0 |
Other operation and maintenance |  |  |  |  |  |  |  |  | 110.1 | 50.0 | 0.0 |
Depreciation and amortization |  |  |  |  |  |  |  |  | 21.1 | 10.0 | 0.0 |
Operating income (loss) |  |  |  |  |  |  |  |  | 49.9 | 6.0 | 0.0 |
Equity in earnings of transmission affiliate |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Interest expense |  |  |  |  |  |  |  |  | 8.5 | 5.1 | 0.0 |
Capital expenditures |  |  |  |  |  |  |  |  | 59.5 | 34.7 | 0.0 |
Total assets | 995.1 |  |  |  | 918.0 |  |  |  | 995.1 | 918.0 | 0.0 |
Regulated operations | Other States | Intersegment revenues |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Regulated operations | Electric transmission |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
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 affiliate |  |  |  |  |  |  |  |  | 146.5 | 96.1 | 66.0 |
Interest expense |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Capital expenditures |  |  |  |  |  |  |  |  | 0.0 | 0.0 | 0.0 |
Total assets | $ 1,476.9 |  |  |  | $ 1,381.0 |  |  |  | 1,476.9 | 1,381.0 | 424.1 |
Regulated operations | Electric transmission | Intersegment revenues |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | $ 0.0 | 0.0 | 0.0 |
ATC |  |  |  |  |  |  |  |  |  |  |  |
Segment information |  |  |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership interest (as a percent) | 60.00% |  |  |  |  |  |  |  | 60.00% |  |  | 26.20%
Equity in earnings of transmission affiliate |  |  |  |  |  |  |  |  | $ 146.5 | $ 96.1 | $ 66.0 |

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