IDENTIFIED INTANGIBLE ASSETS AND LIABILITIES - Schedule of Estimated Annual Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Finite-Lived Intangible Assets [Line Items]
Amortization of acquired below-market leases, net of above-market leases	$ 2,200	$ 9,400	$ 4,500	$ 11,800
Below-Market Operating Lease Amortization
Reminder of 2019	4,898		4,898
2019	9,703		9,703
2020	9,627		9,627
2021	9,575		9,575
2022	9,339		9,339
2024	9,167		9,167
In-Place Leases
Amortization of Intangible Assets	2,200	$ 1,900	4,200	$ 4,000
Above-Market
Above-Market Operating Lease Amortization
Remainder of 2019	(513)		(513)
2020	(860)		(860)
2021	(495)		(495)
2022	(386)		(386)
2023	(321)		(321)
2024	(142)		(142)
In-Place Leases
Remainder of 2019	(513)		(513)
2020	(860)		(860)
2021	(495)		(495)
2022	(386)		(386)
2023	(321)		(321)
2024	(142)		(142)
In-Place Leases
Above-Market Operating Lease Amortization
Remainder of 2019	(4,360)		(4,360)
2020	(7,605)		(7,605)
2021	(6,005)		(6,005)
2022	(4,859)		(4,859)
2023	(4,366)		(4,366)
2024	(3,732)		(3,732)
In-Place Leases
Remainder of 2019	(4,360)		(4,360)
2020	(7,605)		(7,605)
2021	(6,005)		(6,005)
2022	(4,859)		(4,859)
2023	(4,366)		(4,366)
2024	$ (3,732)		$ (3,732)

Amortization Of Acquired Below-Market Lease, Net Of Acquired Above-Market Lease

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Below Market Lease, Net Of Above Market Lease, Amortization Income, Reminder of Fiscal Year

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Below Market Lease, Net Of Above Market Lease, Amortization Income, Year Five

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Below Market Lease, Net Of Above Market Lease, Amortization Income, Year Four

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Below Market Lease, Net Of Above Market Lease, Amortization Income, Year Six

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Below Market Lease, Net Of Above Market Lease, Amortization Income, Year Three

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Below Market Lease, Net Of Above Market Lease, Amortization Income, Year Two

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Below Market Lease, Net of Above Market Lease, Amortization Income, Fiscal Year Maturity [Abstract]

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Finite-Lived Intangible Assets, Amortization Expense, Year Six

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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.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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