LEASES - Operating and Financing leases (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Balance sheet presentation of our operating and financing leases
Operating lease assets	$ 199		$ 306
Finance lease assets	508		204
Total lease assets	707		510
Operating lease obligations, current	143		225
Finance lease obligations, current	248		48
Operating lease liabilities, less current maturities	64		92
Finance lease liabilities, less current maturities	199		116
Total lease liabilities	654		481
Amounts reclassified to finance lease right-of-use assets	321
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	$ 155		29
Right of Use Asset \| Reclassified to finance lease right of use assets [Member]
Balance sheet presentation of our operating and financing leases
Finance lease assets			29
Property, Plant and Equipment [Member] \| Reclassified to finance lease right of use assets [Member]
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=121603541&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, after accumulated amortization, of right-of-use asset from finance lease.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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

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

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

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=121603541&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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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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-Topic 842
-SubTopic 20
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-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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