Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Other, Net	$ 6,135,212	$ 5,628,840
Property, plant and equipment	8,468,967	7,834,557
Public Utilities, Property, Plant and Equipment, Accumulated Depreciation	$ (2,333,755)	$ (2,205,717)
Minimum [Member]
Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	2.50%	2.50%	2.50%
Maximum [Member]
Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	3.50%	3.50%	3.50%
Regulated Operation
Property, Plant and Equipment [Abstract]
Interest Costs Capitalized	$ 5,700	$ 4,500	$ 4,200
Property, Plant and Equipment [Line Items]
Interest Costs Capitalized	5,700	4,500	4,200
Construction in Progress Expenditures Incurred but Not yet Paid	36,200	28,600	$ 25,600
Property, plant and equipment		7,834,557
Public Utilities, Property, Plant and Equipment, Accumulated Depreciation	(2,333,755)	(2,205,717)
Regulated Operation | Gas Distribution Equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	6,716,074	6,240,236
Regulated Operation | Gas Transmission Equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	713,505	661,379
Regulated Operation | Land, Buildings and Improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment	907,946	782,870
Regulated Operation | Construction in Progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 131,442	$ 150,072