SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Schedule of Useful Life) (Details)	12 Months Ended
	Dec. 31, 2016
Building [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Useful life	25 years
Building [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Useful life	40 years
Building Improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Useful life	10 years
Building Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Useful life	40 years
Tenant Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	Shorter of lease term or expected useful life
Tenant Origination and Absorption Costs [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	Remaining term of related leases, including below-market renewal periods