Segments - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information
General contracting and real estate services revenues	$ 57,398	$ 21,444	$ 104,666	$ 38,480
General contracting and real estate services | General contracting and real estate services | Intercompany Eliminations
Segment Reporting Information
General contracting and real estate services revenues	8,400	30,000	21,500	60,200
General contracting and real estate services expenses	$ 8,300	$ 29,700	$ 21,300	$ 59,600