CREDIT FACILITIES AND LONG-TERM DEBT - Mortgage Financing (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Borrowing Capacity	$ 449,000,000
Outstanding Amount	140,000,000
Repo Facility 2019-R1 \| Secured Debt
Debt Instrument [Line Items]
Borrowing Capacity	50,000,000.0
Outstanding Amount	$ 7,149,000	$ 2,021,000
Weighted average interest rate (in percent)	1.94%	3.98%
Amount fully committed	$ 20,000,000.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant