Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 7,554,063	$ 7,081,267	$ 6,629,518
Less accumulated depreciation and amortization	2,209,771	2,076,375	$ 1,963,260
Net property, plant and equipment	5,344,292	5,004,892
Electric | Electric Equipment
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 1,014,906	939,474
Weighted Average Depreciable Life in Years	49 years
Electric | Electric Distribution
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 546,121	521,215
Weighted Average Depreciable Life in Years	47 years
Electric | Electric Transmission
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 662,466	639,999
Weighted Average Depreciable Life in Years	65 years
Electric | CWIP
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 81,316	115,103
Electric | Other
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 176,007	153,248
Weighted Average Depreciable Life in Years	15 years
Natural gas distribution | CWIP
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 74,207	70,373
Natural gas distribution | Other
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 282,007	246,991
Weighted Average Depreciable Life in Years	15 years
Natural gas distribution | Gas Distribution
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 2,955,435	2,771,540
Weighted Average Depreciable Life in Years	53 years
Natural gas distribution | Gas Transmission
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 146,710	115,057
Weighted Average Depreciable Life in Years	56 years
Natural gas distribution | Storage
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 43,700	42,654
Weighted Average Depreciable Life in Years	37 years
Natural gas distribution | General
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 229,034	215,572
Weighted Average Depreciable Life in Years	13 years
Pipeline | CWIP
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 29,629	57,038
Pipeline | Other
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 73,749	68,194
Weighted Average Depreciable Life in Years	17 years
Pipeline | Gas Transmission
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 1,173,259	1,035,995
Weighted Average Depreciable Life in Years	46 years
Pipeline | Storage
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 61,369	57,160
Weighted Average Depreciable Life in Years	53 years
Other | Land and other
Property, plant and equipment [Line Items]
Property, plant and equipment	$ 4,148	$ 31,654
Weighted Average Depreciable Life in Years	7 years