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Property, Plant, and Equipment (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 9,364,038 | $ 8,972,849 |
Less accumulated depreciation, depletion and amortization | 3,272,493 | 3,216,461 | $ 3,133,831
Net property, plant and equipment | 6,091,545 | 5,756,388 | 5,166,939
Electric |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | 2,276,613 | 2,295,646 | 2,323,403
Natural gas distribution |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | 3,208,060 | 3,015,164 | 2,868,853
Pipeline |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | 1,108,141 | 1,051,868 | 821,697
Construction materials and contracting |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | 2,489,408 | 2,347,696 | 2,028,476
Construction services |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | 245,111 | 225,758 | 220,796
Other |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | 36,705 | 36,717 | $ 37,545
Regulated Operation | Electric | Electric Generation Equipment |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 938,614 | 1,056,632 |
Weighted average depreciable life in years | 48 years |  |
Regulated Operation | Electric | Electric Distribution |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 489,351 | 474,037 |
Weighted average depreciable life in years | 47 years |  |
Regulated Operation | Electric | Electric Transmission |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 616,611 | 562,080 |
Weighted average depreciable life in years | 65 years |  |
Regulated Operation | Electric | Construction in Progress |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 87,003 | 62,781 |
Regulated Operation | Electric | Other Capitalized Property Plant and Equipment |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 145,034 | 140,117 |
Weighted average depreciable life in years | 14 years |  |
Regulated Operation | Natural gas distribution | Construction in Progress |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 55,759 | 21,741 |
Regulated Operation | Natural gas distribution | Other Capitalized Property Plant and Equipment |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 230,299 | 225,272 |
Weighted average depreciable life in years | 15 years |  |
Regulated Operation | Natural gas distribution | Gas Distribution [Member] |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 2,569,921 | 2,427,779 |
Weighted average depreciable life in years | 52 years |  |
Regulated Operation | Natural gas distribution | Gas Transmission [Member] |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 104,769 | 107,721 |
Weighted average depreciable life in years | 61 years |  |
Regulated Operation | Natural gas distribution | Natural gas storage |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 42,318 | 34,997 |
Weighted average depreciable life in years | 37 years |  |
Regulated Operation | Natural gas distribution | General |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 204,993 | 197,653 |
Weighted average depreciable life in years | 13 years |  |
Regulated Operation | Pipeline | Construction in Progress |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 34,655 | 263,640 |
Regulated Operation | Pipeline | Other Capitalized Property Plant and Equipment |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 59,917 | 50,477 |
Weighted average depreciable life in years | 19 years |  |
Regulated Operation | Pipeline | Gas Transmission [Member] |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 951,187 | 673,344 |
Weighted average depreciable life in years | 46 years |  |
Regulated Operation | Pipeline | Natural gas storage |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 55,383 | 57,670 |
Weighted average depreciable life in years | 53 years |  |
Nonregulated Operation | Pipeline | Construction in Progress |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 49 | 18 |
Nonregulated Operation | Pipeline | Other Capitalized Property Plant and Equipment |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 6,950 | 6,719 |
Weighted average depreciable life in years | 10 years |  |
Nonregulated Operation | Construction materials and contracting | Construction in Progress |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 88,163 | 50,425 |
Nonregulated Operation | Construction materials and contracting | Land [Member] |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | 150,809 | 149,066 |
Nonregulated Operation | Construction materials and contracting | Building and Building Improvements [Member] |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 165,833 | 149,262 |
Weighted average depreciable life in years | 21 years |  |
Nonregulated Operation | Construction materials and contracting | Machinery, vehicles and equipment |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 1,492,506 | 1,414,260 |
Weighted average depreciable life in years | 12 years |  |
Nonregulated Operation | Construction materials and contracting | Aggregate reserves [Member] |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 592,097 | 584,683 |
Nonregulated Operation | Construction services | Other Capitalized Property Plant and Equipment |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 6,643 | 13,467 |
Weighted average depreciable life in years | 4 years |  |
Nonregulated Operation | Construction services | Land [Member] |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 8,234 | 6,513 |
Nonregulated Operation | Construction services | Building and Building Improvements [Member] |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 50,776 | 39,039 |
Weighted average depreciable life in years | 24 years |  |
Nonregulated Operation | Construction services | Machinery, vehicles and equipment |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 179,459 | 166,739 |
Weighted average depreciable life in years | 7 years |  |
Nonregulated Operation | Other | Other Capitalized Property Plant and Equipment |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 34,057 | 34,069 |
Weighted average depreciable life in years | 7 years |  |
Nonregulated Operation | Other | Land [Member] |  |  |
Property, plant and equipment [Line Items] |  |  |
Property, Plant and Equipment, Gross | $ 2,648 | $ 2,648 |

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