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v3.24.1.u1

Segment Information - Significant Segment Financial Data (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | $ 178.7 | $ 220.2 |
Segment Profit (Loss) | 27.2 | 24.1 |
Capital Expenditures | 20.2 | 22.2 |
Segment Assets | 1,697.9 | 1,614.7 | $ 1,670.4
Billed and Unbilled Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 171.4 | 219.5 |
Rate Adjustment Mechanism Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 7.3 | 0.7 |
Gas Segment |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 105.1 | 112.0 |
Segment Profit (Loss) | 22.4 | 19.0 |
Capital Expenditures | 10.7 | 11.5 |
Segment Assets | 1,043.7 | 979.2 |
Gas Segment | Billed and Unbilled Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 100.4 | 121.9 |
Gas Segment | Rate Adjustment Mechanism Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 4.7 | (9.9) |
Electric |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 73.6 | 108.2 |
Segment Profit (Loss) | 4.9 | 5.3 |
Capital Expenditures | 8.7 | 10.6 |
Segment Assets | 625.5 | 613.7 |
Electric | Billed and Unbilled Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 71.0 | 97.6 |
Electric | Rate Adjustment Mechanism Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 2.6 | 10.6 |
All Other Segments |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Segment Profit (Loss) | (0.1) | (0.2) |
Capital Expenditures | 0.8 | 0.1 |
Segment Assets | $ 28.7 | $ 21.8 |

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