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v3.23.1

Significant Segment Financial Data (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | $ 220.2 | $ 192.6 |
Segment Profit (Loss) | 24.1 | 21.5 |
Capital Expenditures | 22.2 | 15.4 |
Segment Assets | 1,614.7 | 1,552.3 | $ 1,590.4
Billed and Unbilled Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 219.5 | 198.4 |
Rate Adjustment Mechanism Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 0.7 | (5.8) |
Gas Segment |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 112.0 | 103.4 |
Segment Profit (Loss) | 19.0 | 18.5 |
Capital Expenditures | 11.5 | 9.0 |
Segment Assets | 979.2 | 932.6 |
Gas Segment | Billed and Unbilled Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 121.9 | 113.7 |
Gas Segment | Rate Adjustment Mechanism Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | (9.9) | (10.3) |
Electric |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 108.2 | 89.2 |
Segment Profit (Loss) | 5.3 | 3.4 |
Capital Expenditures | 10.6 | 6.3 |
Segment Assets | 613.7 | 598.2 |
Electric | Billed and Unbilled Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 97.6 | 84.7 |
Electric | Rate Adjustment Mechanism Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 10.6 | 4.5 |
All Other Segments |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Segment Profit (Loss) | (0.2) | (0.4) |
Capital Expenditures | 0.1 | 0.1 |
Segment Assets | $ 21.8 | $ 21.5 |

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