RELATED-PARTY TRANSACTIONS - Due to Related Parties (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Due to related parties	$ 6,918	$ 6,706
Asset management fees | Affiliated Entity
Related Party Transaction [Line Items]
Due to related parties	2,227	2,386
Property management fees and reimbursements | Affiliated Entity | CIM Management Entities
Related Party Transaction [Line Items]
Due to related parties	1,753	1,662
Expense Reimbursements | Affiliated Entity | Non-segment
Related Party Transaction [Line Items]
Due to related parties	846	647
Expense Reimbursements | Affiliated Entity | Operating Segments
Related Party Transaction [Line Items]
Due to related parties	612	690
Upfront dealer manager and trailing dealer manager fees | Affiliated Entity
Related Party Transaction [Line Items]
Due to related parties	541	493
Non-issuance specific offering costs | Affiliated Entity
Related Party Transaction [Line Items]
Due to related parties	723	668
Other amounts due to the CIM Management Entities and certain of its affiliates | Affiliated Entity | CIM Management Entities And Related Parties
Related Party Transaction [Line Items]
Due to related parties	$ 216	$ 160