Construction Contracts - Summary of Net Position (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Contractors [Abstract]
Costs incurred on uncompleted construction contracts	$ 796,457	$ 695,564
Estimated earnings	28,275	24,553
Billings	(833,719)	(725,174)
Net position	(8,987)	(5,057)
Construction contract costs and estimated earnings in excess of billings, net	333	249	$ 461	$ 1,358
Billings in excess of construction contract costs and estimated earnings	$ (9,320)	$ (5,306)	$ (1,789)	$ (3,037)