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v3.23.1

Revenue Recognition (Disaggregation of Revenue) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Disaggregation of Revenue [Line Items] |  |
Customer revenues | $ 1,896.1 | $ 1,840.3
Other revenues | 69.9 | 33.0
Total Operating Revenues | 1,966.0 | 1,873.3
Revenues | 1,966.0 | 1,873.3
Gas Distribution Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 1,455.1 | 1,433.9
Other revenues | 46.2 | 2.8
Revenues | 1,504.4 | 1,439.8
Gas Distribution Operations | Unaffiliated |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 1,501.3 | 1,436.7
Electric Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 441.0 | 406.4
Other revenues | 23.5 | 23.7
Revenues | 464.7 | 430.3
Electric Operations | Unaffiliated |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 464.5 | 430.1
Corporate and Other |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 0.0 | 0.0
Other revenues | 0.2 | 6.5
Revenues | 116.9 | 120.0
Corporate and Other | Unaffiliated |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 0.2 | 6.5
Residential |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 1,137.4 | 1,115.4
Residential | Gas Distribution Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 987.0 | 976.9
Residential | Electric Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 150.4 | 138.5
Residential | Corporate and Other |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 0.0 | 0.0
Commercial |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 511.5 | 491.0
Commercial | Gas Distribution Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 360.6 | 356.5
Commercial | Electric Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 150.9 | 134.5
Commercial | Corporate and Other |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 0.0 | 0.0
Industrial |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 206.1 | 197.6
Industrial | Gas Distribution Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 71.9 | 67.8
Industrial | Electric Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 134.2 | 129.8
Industrial | Corporate and Other |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 0.0 | 0.0
Off-system |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 17.2 | 18.7
Off-system | Gas Distribution Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 17.2 | 18.7
Off-system | Electric Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 0.0 | 0.0
Off-system | Corporate and Other |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 0.0 | 0.0
Miscellaneous |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 23.9 | 17.6
Miscellaneous | Gas Distribution Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 18.4 | 14.0
Miscellaneous | Electric Operations |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | 5.5 | 3.6
Miscellaneous | Corporate and Other |  |
Disaggregation of Revenue [Line Items] |  |
Customer revenues | $ 0.0 | $ 0.0

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