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v3.23.2

Components of Gas and Electric Operating Revenue (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | $ 103.4 | $ 98.9 | $ 323.6 | $ 291.5
Billed and Unbilled Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 115.1 | 113.7 | 334.6 | 312.1
Rate Adjustment Mechanism Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | (11.7) | (14.8) | (11.0) | (20.6)
Electric |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 64.5 | 54.3 | 172.7 | 143.5
Electric | Billed and Unbilled Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 69.8 | 64.1 | 167.4 | 148.8
Electric | Rate Adjustment Mechanism Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | (5.3) | (9.8) | 5.3 | (5.3)
Gas Segment |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 38.9 | 44.6 | 150.9 | 148.0
Gas Segment | Billed and Unbilled Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 45.3 | 49.6 | 167.2 | 163.3
Gas Segment | Rate Adjustment Mechanism Revenue |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | (6.4) | (5.0) | (16.3) | (15.3)
Residential |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 57.7 | 51.9 | 166.9 | 146.6
Residential | Electric |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 39.8 | 33.8 | 99.9 | 83.0
Residential | Gas Segment |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 17.9 | 18.1 | 67.0 | 63.6
Commercial & Industrial |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 54.5 | 53.7 | 158.5 | 149.4
Commercial & Industrial | Electric |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 28.1 | 25.7 | 62.9 | 56.7
Commercial & Industrial | Gas Segment |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 26.4 | 28.0 | 95.6 | 92.7
Other |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 2.9 | 8.1 | 9.2 | 16.1
Other | Electric |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | 1.9 | 4.6 | 4.6 | 9.1
Other | Gas Segment |  |  |  |
Operating Revenues [Line Items] |  |  |  |
Total Gas and Electric Operating Revenues | $ 1.0 | $ 3.5 | $ 4.6 | $ 7.0

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