Real Estate Investments (Concentrations) (Details)	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
New Jersey
Concentration Risk [Line Items]
Concentration risk	20.00%	20.30%
Georgia
Concentration Risk [Line Items]
Concentration risk	11.00%	11.20%
SunTrust Bank
Concentration Risk [Line Items]
Concentration risk	17.80%	17.90%
Sanofi US
Concentration Risk [Line Items]
Concentration risk	11.40%	11.60%
C&S Wholesale Grocer
Concentration Risk [Line Items]
Concentration risk	10.20%	10.40%

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=51801978&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=49121117&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=51801978&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=49121117&loc=d3e13537-108611

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Data Type:	num:percentItemType
Balance Type:	na
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