Segments - Net Income of Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information
Rental revenues	$ 39,636	$ 42,220	$ 121,840	$ 109,507
Rental expenses	10,223	9,873	27,907	24,513
Real estate taxes	4,760	4,180	13,326	10,759
Segment revenues	58,617	27,638	163,283	66,118
Operating Segments
Segment Reporting Information
Gross profit	26,761	29,359	86,489	77,498
Operating Segments \| Office real estate
Segment Reporting Information
Rental revenues	11,456	10,283	32,142	23,221
Rental expenses	3,042	2,753	7,879	6,092
Real estate taxes	1,375	1,141	3,749	2,320
Gross profit	7,039	6,389	20,514	14,809
Operating Segments \| Retail real estate
Segment Reporting Information
Rental revenues	15,669	20,780	54,794	57,272
Rental expenses	2,618	3,096	8,096	8,556
Real estate taxes	1,808	2,219	5,981	5,923
Gross profit	11,243	15,465	40,717	42,793
Operating Segments \| Multifamily residential real estate
Segment Reporting Information
Rental revenues	12,511	11,157	34,904	29,014
Rental expenses	4,563	4,024	11,932	9,865
Real estate taxes	1,577	820	3,596	2,516
Gross profit	6,371	6,313	19,376	16,633
Operating Segments \| General contracting and real estate services \| General contracting and real estate services
Segment Reporting Information
Segment revenues	58,617	27,638	163,283	66,118
Segment expenses	56,509	26,446	157,401	62,855
Gross profit	$ 2,108	$ 1,192	$ 5,882	$ 3,263

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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