RELATED PARTY TRANSACTIONS (Related-party Costs) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Payable as of	$ 649	$ 235
Insurance expense	260	389	$ 335
Advisor and Dealer Manager
Related Party Transaction [Line Items]
Incurred	4,718	5,830	13,705
Payable as of	649	235
Advisor and Dealer Manager \| Asset Management Fees
Related Party Transaction [Line Items]
Expensed	4,093	3,985	2,775
Payable as of	620	22
Advisor and Dealer Manager \| Reimbursable Operating Expenses
Related Party Transaction [Line Items]
Expensed	315	477	339
Payable as of	0	35
Advisor and Dealer Manager \| Disposition Fee
Related Party Transaction [Line Items]
Expensed	281	0	0
Payable as of	0	0
Advisor and Dealer Manager \| Acquisition fees
Related Party Transaction [Line Items]
Expensed	29	228	4,943
Payable as of	29	178
Advisor and Dealer Manager \| Asset Management Fees
Related Party Transaction [Line Items]
Expensed	0	0	67
Payable as of	0	0
Advisor and Dealer Manager \| Sales Commissions
Related Party Transaction [Line Items]
Incurred	0	614	2,412
Payable as of	0	0
Advisor and Dealer Manager \| Dealer Manager Fees
Related Party Transaction [Line Items]
Incurred	0	337	1,352
Payable as of	0	0
Advisor and Dealer Manager \| Stockholder Servicing Fees
Related Party Transaction [Line Items]
Incurred	0	14	1,149
Payable as of	0	0
Advisor and Dealer Manager \| Reimbursable Other Offering Costs
Related Party Transaction [Line Items]
Incurred	0	175	$ 668
Payable as of	$ 0	$ 0

Carrying amount as of the balance sheet date of obligations due all related parties.

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