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v3.25.2

Components of Gas and Electric Operating Revenue (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | $ 102.6 | $ 95.7 | $ 273.4 | $ 274.4
Billed and Unbilled Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 99.8 | 105.8 | 294.9 | 277.1
Rate Adjustment Mechanism Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 2.8 | (10.1) | (21.5) | (2.7)
Electric |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 51.0 | 56.4 | 111.2 | 130.0
Electric | Billed and Unbilled Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 47.0 | 58.8 | 107.8 | 129.8
Electric | Rate Adjustment Mechanism Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 4.0 | (2.4) | 3.4 | 0.2
Gas Segment |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 51.6 | 39.3 | 162.2 | 144.4
Gas Segment | Billed and Unbilled Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 52.8 | 47.0 | 187.1 | 147.3
Gas Segment | Rate Adjustment Mechanism Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | (1.2) | (7.7) | (24.9) | (2.9)
Residential |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 44.5 | 48.8 | 133.4 | 130.4
Residential | Electric |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 23.4 | 30.4 | 56.6 | 71.0
Residential | Gas Segment |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 21.1 | 18.4 | 76.8 | 59.4
Commercial & Industrial |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 51.0 | 53.3 | 144.9 | 136.5
Commercial & Industrial | Electric |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 21.0 | 26.3 | 44.5 | 54.3
Commercial & Industrial | Gas Segment |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 30.0 | 27.0 | 100.4 | 82.2
Other |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 4.3 | 3.7 | 16.6 | 10.2
Other | Electric |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | 2.6 | 2.1 | 6.7 | 4.5
Other | Gas Segment |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Electric and Gas Operating Revenues | $ 1.7 | $ 1.6 | $ 9.9 | $ 5.7

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