REAL ESTATE HELD FOR INVESTMENT - Highest Tenant Industry Concentrations - Greater than 10% of Annual Base Rent (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($) tenant
Concentration Risk [Line Items]
Number of Tenants	60
Professional, scientific and technical
Concentration Risk [Line Items]
Number of Tenants	9
Annualized Base Rent \| $	$ 4,980
Percentage of Annualized Base Rent	37.60%
Computer system design and related services
Concentration Risk [Line Items]
Number of Tenants	2
Annualized Base Rent \| $	$ 1,358
Percentage of Annualized Base Rent	10.20%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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