LEASES - Future minimum lease payments (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Maturity of lease liabilities
Initial lease term (in months)	36 months	36 months
2019 (excluding the six months ended June 30, 2019)	$ 118,000	$ 118,000
2020	235,500	235,500
2021	235,500	235,500
2022	59,000	59,000
Total received leases	648,000	648,000
Rental income	29,000	29,000
ASU No. 2016-02, Leases (Topic 842)
Maturity of lease liabilities
2019 (excluding the six months ended June 30, 2019)	26,000	26,000
2020	52,000	52,000
2021	52,000	52,000
2022	52,000	52,000
2023	10,000	10,000
Total lease payments	192,000	192,000
Less: Amounts representing interest	(12,000)	(12,000)
Present value of lease liabilities	$ 180,000	$ 180,000

Amount of lessee's undiscounted obligation for lease payments for operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ References

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of lease payments to be received by lessor for operating lease.

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Amount of lease payments to be received by lessor in next fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lease payments to be received by lessor in remainder of fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lease payments to be received by lessor in third fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lease payments to be received by lessor in second fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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