Goodwill and Intangible Assets (Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Total Intangible Assets [Abstract]
Cost	$ 381,940	$ 381,940
Accumulated Amortization	(200,568)	(198,331)
Accumulated Impairment Charge	(113,067)	(113,067)
Carrying Value	68,305	70,542
Trade Names
Finite-Lived intangible assets
Cost	69,250	69,250
Accumulated Amortization	(28,123)	(25,886)
Accumulated Impairment Charge	(23,232)	(23,232)
Carrying Value	$ 17,895	$ 20,132
Weighted-Average Amortization Period	20 years	20 years
Customer relationships
Finite-Lived intangible assets
Cost	$ 39,800	$ 39,800
Accumulated Amortization	(23,155)	(23,155)
Accumulated Impairment Charge	(16,645)	(16,645)
Carrying Value	0	0
Construction contract backlog
Finite-Lived intangible assets
Cost	149,290	149,290
Accumulated Amortization	(149,290)	(149,290)
Carrying Value	0	0
Trade Names
Indefinite-lived intangible assets
Cost	117,600	117,600
Accumulated Impairment Charge	(67,190)	(67,190)
Carrying Value	50,410	50,410
Contractor license
Indefinite-lived intangible assets
Cost	6,000	6,000
Accumulated Impairment Charge	$ (6,000)	$ (6,000)