INTANGIBLE ASSETS AND LIABILITIES - Summary of Real Estate Intangible Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets
(Decrease) increase to rental income related to above/below market leases, net	$ 7,701	$ (912)	$ 0
(Decrease) increase to rental income related to above/below market leases, net
Finite-Lived Intangible Assets
(Decrease) increase to rental income related to above/below market leases, net	7,701	(912)	0
Depreciation and amortization related to tenant origination and absorption costs and tenant relationship
Finite-Lived Intangible Assets
Depreciation and amortization related to tenant origination and absorption costs and tenant relationship	$ (16,118)	$ (11,822)	$ (3,182)

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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