ACQUISITIONS (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015 USD ($) ft²	Dec. 31, 2014	Sep. 30, 2014 USD ($)
Acquired in-place Leases
Fair value of the assets acquired and liabilities assumed
Weighted average amortization period	8 years	8 years
Two Kaiser Plaza
Acquisitions
Interest acquired (as a percent)	100.00%
Rentable space (in square feet ) | ft²	44,642
Purchase Price	$ 11,143
Fair value of the assets acquired and liabilities assumed
Net assets acquired	11,143
Other disclosures
Acquisition related expenses	102		$ 32
Two Kaiser Plaza | Acquired in-place Leases
Fair value of the assets acquired and liabilities assumed
Intangible assets	$ 102
Weighted average amortization period	3 years
Two Kaiser Plaza | Land
Fair value of the assets acquired and liabilities assumed
Property, plant and equipment	$ 10,931
Two Kaiser Plaza | Land improvements
Fair value of the assets acquired and liabilities assumed
Property, plant and equipment	$ 110