REAL ESTATE HELD FOR INVESTMENT (Highest Tenant Industry Concentrations- Greater than 10% of Annual Base Rent) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2017 USD ($) tenant
Concentration Risk [Line Items]
Number of tenants \| tenant	600
Annualized Base Rent \| $	$ 23,251
Percentage of Annualized Base Rent	21.60%
Insurance Carriers & Related Activities
Concentration Risk [Line Items]
Number of tenants \| tenant	35
Annualized Base Rent \| $	$ 11,844
Percentage of Annualized Base Rent	11.00%
Computer System Design & Programming
Concentration Risk [Line Items]
Number of tenants \| tenant	57
Annualized Base Rent \| $	$ 11,407
Percentage of Annualized Base Rent	10.60%

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

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