Construction Contracts (Net Position of Uncompleted Construction Contracts) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Contractors [Abstract]
Costs incurred on uncompleted construction contracts	$ 594,006	$ 520,368
Estimated earnings	20,375	18,070
Billings	(616,060)	(541,784)
Net position	(1,679)	(3,346)
Construction contract costs and estimated earnings in excess of billings	1,358	245
Billings in excess of construction contract costs and estimated earnings	$ (3,037)	$ (3,591)

Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings.

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