Property, Plant, and Equipment

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment Disclosure

Property, Plant and Equipment

Property, plant and equipment at December 31 was as follows:

	2022		2021		Weighted Average Depreciable Life in Years
	(Dollars in thousands, where applicable)
Regulated:
Electric:
Generation	$	938,614	$	1,056,632	48
Distribution	489,351		474,037		47
Transmission	616,611		562,080		65
Construction in progress	87,003		62,781		—
Other	145,034		140,117		14
Natural gas distribution:
Distribution	2,569,921		2,427,779		52
Transmission	104,769		107,721		61
Storage	42,318		34,997		37
General	204,993		197,653		13
Construction in progress	55,759		21,741		—
Other	230,299		225,272		15
Pipeline:
Transmission	951,187		673,344		46
Storage	55,383		57,670		53
Construction in progress	34,655		263,640		—
Other	59,917		50,477		19
Non-regulated:
Pipeline:
Construction in progress	49		18		—
Other	6,950		6,719		10
Construction materials and contracting:
Land	150,809		149,066		—
Buildings and improvements	165,833		149,262		21
Machinery, vehicles and equipment	1,492,506		1,414,260		12
Construction in progress	88,163		50,425		—
Aggregate reserves	592,097		584,683		*
Construction services:
Land	8,234		6,513		—
Buildings and improvements	50,776		39,039		24
Machinery, vehicles and equipment	179,459		166,739		7
Other	6,643		13,467		4
Other:
Land	2,648		2,648		—
Other	34,057		34,069		7
Less accumulated depreciation, depletion and amortization	3,272,493		3,216,461
Net property, plant and equipment	$	6,091,545	$	5,756,388

*Depleted on the units-of-production method based on proven and probable aggregate reserves.