Segments - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information
Non-cash stock compensation			$ 1,072	$ 1,047
General and Administrative Expense
Segment Reporting Information
Non-cash stock compensation	$ 200	$ 200	900	800
General contracting and real estate services
Segment Reporting Information
Non-cash stock compensation	100	100	200	200
General contracting and real estate services
Segment Reporting Information
General contracting and real estate services revenues	19,950	41,201	63,654	161,391
General contracting and real estate services expenses	18,973	39,377	61,474	154,588
General contracting and real estate services \| General contracting and real estate services \| Intercompany Eliminations
Segment Reporting Information
General contracting and real estate services revenues	38,500	13,900	98,600	31,300
General contracting and real estate services expenses	$ 38,200	$ 13,700	$ 97,700	$ 31,000

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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