Segments - Net Income of Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information
Rental expenses	$ 9,375	$ 6,725
Real estate taxes	4,333	3,128
Segment revenues	47,268	17,036
Segment expenses	45,550	16,286
Rental revenues	42,289	30,909
Operating Segments
Segment Reporting Information
Gross profit	30,299	21,806
Operating Segments \| Office real estate
Segment Reporting Information
Rental expenses	2,546	1,486
Real estate taxes	1,146	526
Gross profit	6,500	3,544
Rental revenues	10,192	5,556
Operating Segments \| Retail real estate
Segment Reporting Information
Rental expenses	3,020	2,600
Real estate taxes	2,166	1,811
Gross profit	15,225	12,846
Rental revenues	20,411	17,257
Operating Segments \| Multifamily residential real estate
Segment Reporting Information
Rental expenses	3,809	2,639
Real estate taxes	1,021	791
Gross profit	6,856	4,666
Rental revenues	11,686	8,096
Operating Segments \| General contracting and real estate services \| General contracting and real estate services
Segment Reporting Information
Segment revenues	47,268	17,036
Segment expenses	45,550	16,286
Gross profit	$ 1,718	$ 750

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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Amount of expense incurred and directly related to generating revenue from leased and rented property or equipment.

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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