OTHER INTANGIBLE ASSETS AND LIABILITIES - Future Amortization and Accretion of Acquisition Related Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Future amortization of acquisition related intangible assets
Net	$ 5,498	$ 6,313
Future accretion of acquisition related intangible liabilities
Net	(309)	(587)
Acquired below-market leases
Future accretion of acquisition related intangible liabilities
2021 (Three months ending December 31, 2021)	(71)
2022	(236)
2023	(2)
2024	0
2025	0
Thereafter	0
Net	(309)	(587)
Acquired above-market leases
Future amortization of acquisition related intangible assets
2021 (Three months ending December 31, 2021)	3
2022	12
2023	10
2024	5
2025	1
Thereafter	0
Net	31	40
Acquired In-Place Leases
Future amortization of acquisition related intangible assets
2021 (Three months ending December 31, 2021)	243
2022	813
2023	470
2024	374
2025	171
Thereafter	439
Net	$ 2,510	$ 3,316

Below Market Lease, Amortization Income, After Year Four

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Finite-Lived Intangible Asset, Expected Amortization, After Year Four

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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No definition available.

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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No definition available.

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in remainder of current fiscal year.

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No definition available.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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