Segments - Net Income of Reportable Segments (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
Rental revenues	$ 39,915	$ 36,378	$ 82,204	$ 67,287
Rental expenses	8,309	7,915	17,684	14,640
Real estate taxes	4,233	3,451	8,566	6,579
Segment revenues	57,398	21,444	104,666	38,480
Operating Segments
Segment Reporting Information
Gross profit	29,429	26,333	59,728	48,139
Operating Segments \| Office real estate
Segment Reporting Information
Rental revenues	10,494	7,382	20,686	12,938
Rental expenses	2,291	1,853	4,837	3,339
Real estate taxes	1,228	653	2,374	1,179
Gross profit	6,975	4,876	13,475	8,420
Operating Segments \| Retail real estate
Segment Reporting Information
Rental revenues	18,714	19,235	39,125	36,492
Rental expenses	2,458	2,860	5,478	5,460
Real estate taxes	2,007	1,893	4,173	3,704
Gross profit	14,249	14,482	29,474	27,328
Operating Segments \| Multifamily residential real estate
Segment Reporting Information
Rental revenues	10,707	9,761	22,393	17,857
Rental expenses	3,560	3,202	7,369	5,841
Real estate taxes	998	905	2,019	1,696
Gross profit	6,149	5,654	13,005	10,320
Operating Segments \| General contracting and real estate services \| General contracting and real estate services
Segment Reporting Information
Segment revenues	57,398	21,444	104,666	38,480
Segment expenses	55,342	20,123	100,892	36,409
Gross profit	$ 2,056	$ 1,321	$ 3,774	$ 2,071

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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