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Net rentable area for properties owned.

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RELATED-PARTY TRANSACTIONS - Other Narrative (Details) ft² in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Sep. 16, 2020 USD ($)	Aug. 07, 2019 ft²	May 15, 2019 ft²	Oct. 01, 2015
CIM Management Entities Affiliate
Related Party Transaction [Line Items]
Lease renewal term with related party						5 years
Rental and other property income from related party	$ 0	$ 29
Employment Agreement \| President
Related Party Transaction [Line Items]
Contractual obligation in connection with retirement of company president			$ 450
Employment Agreement \| Affiliated Entity
Related Party Transaction [Line Items]
Due to related party	287
Eleven Year Lease \| CIM Group
Related Party Transaction [Line Items]
Rental and other property income from related party	$ 370	$ 370
Lease, term of contract with related party					11 years
Net rentable area with related party (in sq ft) \| ft²				30	32