LEASES - Operating and Financing leases (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Balance sheet presentation of our operating and financing leases
Operating lease assets	$ 253		$ 306
Finance lease assets	289		204
Total lease assets	542		510
Operating lease obligations, current	186		225
Finance lease obligations, current	136		48
Operating lease obligations, Non-current	77		92
Finance lease obligations, Non-current	112		116
Total lease liabilities	511		481
Amounts reclassified to finance lease right-of-use assets	96
Amounts reclassified to operating lease right-of-use assets	0	$ 0
HemeScreen Reagent Rental [Member]
Balance sheet presentation of our operating and financing leases
Finance lease assets	$ 125		29
Reclassified to finance lease right of use assets [Member] \| Right of Use Asset
Balance sheet presentation of our operating and financing leases
Finance lease assets			29
Reclassified to finance lease right of use assets [Member] \| Property, Plant and Equipment
Balance sheet presentation of our operating and financing leases
Finance lease assets			$ 175

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

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Amount of lessee's right to use underlying asset under operating and finance lease.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under finance lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
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Amount of lessee's right to use underlying asset under operating lease.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

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-Publisher FASB
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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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