LEASES - Operating and Financing leases (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Balance sheet presentation of our operating and financing leases
Operating lease assets	$ 144		$ 306
Finance lease assets	487		204
Total lease assets	631		510
Operating lease obligations, current	93		225
Finance lease obligations, current	244		48
Operating lease liabilities, less current maturities	57		92
Finance lease liabilities, less current maturities	187		116
Total lease liabilities	581		481
Amounts reclassified to finance lease right-of-use assets	346
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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- Definition

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
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-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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-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980

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

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