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LEASES - As Lessee - Ground Lease and Office Lease (Details)	3 Months Ended
	Mar. 31, 2021 USD ($) item	Mar. 31, 2020 USD ($)
Real Estate in Greensboro, NC
Lessee Accounting
Operating lease, option to extend	true
Operating lease, remaining lease term	13 years 10 months 24 days
Operating lease expense | $	$ 150,000	$ 131,000
Real Estate in Greensboro, NC | Maximum
Lessee Accounting
Operating lease, number of renewal options | item	4
Real Estate in Greensboro, NC | Five-Year Lease
Lessee Accounting
Operating lease, renewal term	5 years
Real Estate in Greensboro, NC | Seven-Month Lease
Lessee Accounting
Operating lease, number of renewal options | item	1
Operating lease, renewal term	7 months
Corporate office lease in Great Neck, NY
Lessee Accounting
Operating lease, option to extend	true
Operating lease, remaining lease term	15 years 9 months 18 days
Operating lease expense | $	$ 14,000	$ 14,000
Corporate office lease in Great Neck, NY | Five-Year Lease
Lessee Accounting
Operating lease, renewal term	5 years

X

- Definition

The number of renewal options available to the Company, as defined in the lease agreement.

+ References

No definition available.

+ Details

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- Definition

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+ References

No definition available.

+ Details

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X

- Definition

Indicates (true false) whether lessee has option to extend operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

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- Definition

Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

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X

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

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X

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918638-209977

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- Details

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