RELATED-PARTY TRANSACTIONS - Fees and Expense Reimbursements (Details) - Affiliated Entity - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
C I M Service Provider LLC | Series A Preferred Stock
Related Party Transaction [Line Items]
Related party, shares issued (in shares)	11,273
Asset management fees
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	$ 9,511	$ 12,019	$ 17,880
Property management fees
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	1,670	2,562	4,365
Onsite management and other cost reimbursement
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	3,356	5,852	6,065
Lease commission
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	112	658	1,548
Construction management fees
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	344	525	580
Base service fee
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	282	1,102	1,079
Expense reimbursements to related parties - corporate
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	2,243	2,577	2,783
Expenses reimbursements to related parties - lending segment
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	3,491	2,382	2,445
Upfront dealer manager and trailing dealer manager fees
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	1,149	1,121	0
Non-issuance specific offering costs
Related Party Transaction [Line Items]
Related party, fees and expense reimbursements	99	0	0
Deferred costs	$ 1,500	621	200
Investment Management Agreement | CIM Capital, LLC | Common Stock
Related Party Transaction [Line Items]
Related party, shares issued (in shares)	203,349
Investment Management Agreement | CIM Capital, LLC | Series A Preferred Stock
Related Party Transaction [Line Items]
Related party, shares issued (in shares)	190,459
Personnel Fees
Related Party Transaction [Line Items]
Deferred personnel costs	$ 136	$ 112	$ 330