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v3.22.4

Significant Segment Financial Data (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | $ 563.2 | $ 473.3 | $ 418.6
Interest Income | 2.8 | 1.6 | 2.6
Interest Expense | 28.3 | 27.2 | 26.4
Depreciation & Amortization Expense | 62.6 | 59.5 | 54.5
Income Tax Expense (Benefit) | 11.2 | 11.5 | 10.2
Segment Profit (Loss) | 41.4 | 36.1 | 32.2
Segment Assets | 1,590.4 | 1,540.3 | 1,477.9
Capital Expenditures | 122.1 | 115.0 | 122.6
Billed and Unbilled Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 553.5 | 466.1 | 411.9
Rate Adjustment Mechanism Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 9.7 | 7.2 | 6.7
Electric |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 297.9 | 248.5 | 227.2
Interest Income | 0.9 | 0.8 | 1.1
Interest Expense | 9.1 | 9.0 | 8.7
Depreciation & Amortization Expense | 25.4 | 25.9 | 23.8
Income Tax Expense (Benefit) | 3.1 | 4.5 | 4.7
Segment Profit (Loss) | 15.7 | 14.0 | 12.9
Segment Assets | 580.9 | 584.0 | 571.8
Capital Expenditures | 33.8 | 38.1 | 45.5
Electric | Billed and Unbilled Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 290.2 | 248.5 | 226.7
Electric | Rate Adjustment Mechanism Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 7.7 |  | 0.5
Gas Segment |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 265.3 | 224.8 | 191.4
Interest Income | 1.0 | 0.5 | 1.1
Interest Expense | 16.8 | 15.3 | 14.2
Depreciation & Amortization Expense | 36.3 | 32.6 | 29.8
Income Tax Expense (Benefit) | 8.2 | 7.7 | 7.3
Segment Profit (Loss) | 26.5 | 23.2 | 19.3
Segment Assets | 988.8 | 935.9 | 886.3
Capital Expenditures | 87.6 | 75.8 | 71.1
Gas Segment | Billed and Unbilled Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 263.3 | 217.6 | 185.2
Gas Segment | Rate Adjustment Mechanism Revenue |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Total Operating Revenues | 2.0 | 7.2 | 6.2
All Other Segments |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |
Interest Income | 0.9 | 0.3 | 0.4
Interest Expense | 2.4 | 2.9 | 3.5
Depreciation & Amortization Expense | 0.9 | 1.0 | 0.9
Income Tax Expense (Benefit) | (0.1) | (0.7) | (1.8)
Segment Profit (Loss) | (0.8) | (1.1) |
Segment Assets | 20.7 | 20.4 | 19.8
Capital Expenditures | $ 0.7 | $ 1.1 | $ 6.0

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