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v3.25.3

Revenue: Disaggregation of Revenue (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Revenue from contracts with customers | $ 427.4 | $ 398.6 | $ 1,663.6 | $ 1,513.0
Revenue | 430.2 | 401.6 | 1,674.5 | 1,530.6
Retail - Electric , Natural Gas and Coal |  |  |  |
Revenue from contracts with customers | 329.9 | 303.8 | 1,367.6 | 1,237.2
Transportation |  |  |  |
Revenue from contracts with customers | 43.5 | 43.2 | 143.1 | 130.9
Wholesale |  |  |  |
Revenue from contracts with customers | 5.5 | 6.1 | 16.9 | 21.1
Market - off-system sales |  |  |  |
Revenue from contracts with customers | 16.3 | 10.7 | 38.4 | 22.8
Transmission |  |  |  |
Revenue from contracts with customers | 11.2 | 13.6 | 33.6 | 39.5
Other revenues |  |  |  |
Revenue from contracts with customers | 21.0 | 21.2 | 64.0 | 61.5
Alternative revenue and other |  |  |  |
Revenue | 2.8 | 3.0 | 10.9 | 17.6
Services transferred at a point in time |  |  |  |
Revenue from contracts with customers | 8.8 | 9.3 | 25.9 | 25.9
Services transferred over time |  |  |  |
Revenue from contracts with customers | 418.6 | 389.3 | 1,637.7 | 1,487.1
Inter-segment Eliminations |  |  |  |
Revenue from contracts with customers | (3.9) | (4.5) | (11.7) | (13.4)
Revenue | (3.9) | (4.5) | (11.7) | (13.4)
Inter-segment Eliminations | Retail - Electric , Natural Gas and Coal |  |  |  |
Revenue from contracts with customers | 0.0 | 0.0 | 0.0 | 0.0
Inter-segment Eliminations | Transportation |  |  |  |
Revenue from contracts with customers | (0.1) | (0.0) | (0.3) | (0.0)
Inter-segment Eliminations | Wholesale |  |  |  |
Revenue from contracts with customers | 0.0 | 0.0 | 0.0 | 0.0
Inter-segment Eliminations | Market - off-system sales |  |  |  |
Revenue from contracts with customers | 0.0 | 0.0 | 0.0 | 0.0
Inter-segment Eliminations | Transmission |  |  |  |
Revenue from contracts with customers | 0.0 | 0.0 | 0.0 | 0.0
Inter-segment Eliminations | Other revenues |  |  |  |
Revenue from contracts with customers | (3.8) | (4.5) | (11.4) | (13.4)
Inter-segment Eliminations | Alternative revenue and other |  |  |  |
Revenue | 0.0 | 0.0 | 0.0 | 0.0
Inter-segment Eliminations | Services transferred at a point in time |  |  |  |
Revenue from contracts with customers | 0.0 | 0.0 | 0.0 | 0.0
Inter-segment Eliminations | Services transferred over time |  |  |  |
Revenue from contracts with customers | (3.9) | (4.5) | (11.7) | (13.4)
Operating Segments | Electric Utilities |  |  |  |
Revenue from contracts with customers | 248.8 | 231.6 | 703.0 | 655.7
Revenue | 249.7 | 232.5 | 706.3 | 659.8
Operating Segments | Electric Utilities | Retail - Electric , Natural Gas and Coal |  |  |  |
Revenue from contracts with customers | 201.3 | 186.3 | 570.6 | 529.4
Operating Segments | Electric Utilities | Transportation |  |  |  |
Revenue from contracts with customers | 0.0 | 0.0 | 0.0 | 0.0
Operating Segments | Electric Utilities | Wholesale |  |  |  |
Revenue from contracts with customers | 5.5 | 6.1 | 16.9 | 21.1
Operating Segments | Electric Utilities | Market - off-system sales |  |  |  |
Revenue from contracts with customers | 16.3 | 10.7 | 38.3 | 22.8
Operating Segments | Electric Utilities | Transmission |  |  |  |
Revenue from contracts with customers | 11.1 | 13.6 | 33.3 | 39.1
Operating Segments | Electric Utilities | Other revenues |  |  |  |
Revenue from contracts with customers | 14.6 | 14.9 | 43.9 | 43.3
Operating Segments | Electric Utilities | Alternative revenue and other |  |  |  |
Revenue | 0.9 | 0.9 | 3.3 | 4.1
Operating Segments | Electric Utilities | Services transferred at a point in time |  |  |  |
Revenue from contracts with customers | 8.8 | 9.3 | 25.9 | 25.9
Operating Segments | Electric Utilities | Services transferred over time |  |  |  |
Revenue from contracts with customers | 240.0 | 222.3 | 677.1 | 629.8
Operating Segments | Gas Utilities |  |  |  |
Revenue from contracts with customers | 182.5 | 171.5 | 972.3 | 870.7
Revenue | 184.4 | 173.6 | 979.9 | 884.2
Operating Segments | Gas Utilities | Retail - Electric , Natural Gas and Coal |  |  |  |
Revenue from contracts with customers | 128.6 | 117.5 | 797.0 | 707.8
Operating Segments | Gas Utilities | Transportation |  |  |  |
Revenue from contracts with customers | 43.6 | 43.2 | 143.4 | 130.9
Operating Segments | Gas Utilities | Wholesale |  |  |  |
Revenue from contracts with customers | 0.0 | 0.0 | 0.0 | 0.0
Operating Segments | Gas Utilities | Market - off-system sales |  |  |  |
Revenue from contracts with customers | 0.0 | 0.0 | 0.1 | 0.0
Operating Segments | Gas Utilities | Transmission |  |  |  |
Revenue from contracts with customers | 0.1 | 0.0 | 0.3 | 0.4
Operating Segments | Gas Utilities | Other revenues |  |  |  |
Revenue from contracts with customers | 10.2 | 10.8 | 31.5 | 31.6
Operating Segments | Gas Utilities | Alternative revenue and other |  |  |  |
Revenue | 1.9 | 2.1 | 7.6 | 13.5
Operating Segments | Gas Utilities | Services transferred at a point in time |  |  |  |
Revenue from contracts with customers | 0.0 | 0.0 | 0.0 | 0.0
Operating Segments | Gas Utilities | Services transferred over time |  |  |  |
Revenue from contracts with customers | $ 182.5 | $ 171.5 | $ 972.3 | $ 870.7

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