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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

X

- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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