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v3.25.2

Segment Information - Significant Segment Financial Data (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |
Operation and Maintenance | $ 21.3 | $ 18.6 | $ 43.9 | $ 36.8 |
Depreciation and Amortization | 21.8 | 18.1 | 43.5 | 36.1 |
Provision for Income Taxes | 0.7 | 0.6 | 10.2 | 10.0 |
Net Income Attributable to Common Shares | 4.0 |  | 31.3 |  |
Segment Assets | 1,892.7 | 1,695.0 | 1,892.7 | 1,695.0 | $ 1,794.5
Capital Expenditures |  |  | 72.8 | 56.9 |
Operating Segments [Member] | Electric |  |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |
Total Operating Revenues | 51.0 | 56.4 | 111.2 | 130.0 |
Energy Supply Costs | 25.2 | 31.5 | 57.9 | 78.0 |
Operation and Maintenance | 9.6 | 8.4 | 19.1 | 16.8 |
Depreciation and Amortization | 7.8 | 7.1 | 15.7 | 14.1 |
Other Segment Expenses (Income) | 2.2 | 3.0 | 5.4 | 6.3 |
Interest Income | (0.8) | (0.9) | (1.6) | (1.7) |
Interest Expense | 3.8 | 3.3 | 7.2 | 6.4 |
Provision for Income Taxes | 0.4 | 0.6 | 1.1 | 1.8 |
Net Income Attributable to Common Shares | 2.8 | 3.4 | 6.4 | 8.3 |
Segment Assets | 677.3 | 632.9 | 677.3 | 632.9 |
Capital Expenditures | 16.0 | 11.7 | 37.2 | 20.4 |
Operating Segments [Member] | Gas Segment |  |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |
Total Operating Revenues | 51.6 | 39.3 | 162.2 | 144.4 |
Energy Supply Costs | 14.4 | 8.0 | 54.1 | 52.1 |
Operation and Maintenance | 10.9 | 10.0 | 23.0 | 19.8 |
Depreciation and Amortization | 14.0 | 10.8 | 27.8 | 21.7 |
Other Segment Expenses (Income) | 3.9 | 4.7 | 8.7 | 9.3 |
Interest Income | (0.6) | (0.9) | (1.4) | (1.8) |
Interest Expense | 5.9 | 5.6 | 12.0 | 11.6 |
Provision for Income Taxes | 0.6 | 0.1 | 10.0 | 8.3 |
Net Income Attributable to Common Shares | 2.5 | 1.0 | 28.0 | 23.4 |
Segment Assets | 1,185.5 | 1,035.3 | 1,185.5 | 1,035.3 |
Capital Expenditures | 24.2 | 24.0 | 35.6 | 34.7 |
Operating Segments [Member] | Total Reportable Segments [Member] |  |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |
Total Operating Revenues | 102.6 | 95.7 | 273.4 | 274.4 |
Energy Supply Costs | 39.6 | 39.5 | 112.0 | 130.1 |
Operation and Maintenance | 20.5 | 18.4 | 42.1 | 36.6 |
Depreciation and Amortization | 21.8 | 17.9 | 43.5 | 35.8 |
Other Segment Expenses (Income) | 6.1 | 7.7 | 14.1 | 15.6 |
Interest Income | (1.4) | (1.8) | (3.0) | (3.5) |
Interest Expense | 9.7 | 8.9 | 19.2 | 18.0 |
Provision for Income Taxes | 1.0 | 0.7 | 11.1 | 10.1 |
Net Income Attributable to Common Shares | 5.3 | 4.4 | 34.4 | 31.7 |
Segment Assets | 1,862.8 | 1,668.2 | 1,862.8 | 1,668.2 |
Capital Expenditures | 40.2 | 35.7 | 72.8 | 55.1 |
Operating Segments [Member] | All Other Segments |  |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |
Total Operating Revenues | 0.0 | 0.0 | 0.0 | 0.0 |
Energy Supply Costs | 0.0 | 0.0 | 0.0 | 0.0 |
Operation and Maintenance | 0.8 | 0.2 | 1.8 | 0.2 |
Depreciation and Amortization | 0.0 | 0.2 | 0.0 | 0.3 |
Other Segment Expenses (Income) | (0.2) | (0.5) | (0.2) | (0.4) |
Interest Income | 0.0 | (0.6) | 0.0 | (0.9) |
Interest Expense | 1.0 | 0.9 | 2.2 | 1.1 |
Provision for Income Taxes | (0.3) | (0.1) | (0.9) | (0.1) |
Net Income Attributable to Common Shares | (1.3) | (0.1) | (2.9) | (0.2) |
Segment Assets | 29.9 | 26.8 | 29.9 | 26.8 |
Capital Expenditures | 0.0 | 1.0 | 0.0 | 1.8 |
Operating Segments [Member] | Total [Member] |  |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |
Total Operating Revenues | 102.6 | 95.7 | 273.4 | 274.4 |
Energy Supply Costs | 39.6 | 39.5 | 112.0 | 130.1 |
Operation and Maintenance | 21.3 | 18.6 | 43.9 | 36.8 |
Depreciation and Amortization | 21.8 | 18.1 | 43.5 | 36.1 |
Other Segment Expenses (Income) | 5.9 | 7.2 | 13.9 | 15.2 |
Interest Income | (1.4) | (2.4) | (3.0) | (4.4) |
Interest Expense | 10.7 | 9.8 | 21.4 | 19.1 |
Provision for Income Taxes | 0.7 | 0.6 | 10.2 | 10.0 |
Net Income Attributable to Common Shares | 4.0 | 4.3 | 31.5 | 31.5 |
Segment Assets | 1,892.7 | 1,695.0 | 1,892.7 | 1,695.0 |
Capital Expenditures | $ 40.2 | $ 36.7 | $ 72.8 | $ 56.9 |

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