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BUSINESS COMBINATIONS - Additional Information (Details) $ in Thousands			3 Months Ended
	Nov. 08, 2019 USD ($)	May 01, 2019 USD ($) item shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)	Nov. 29, 2019 USD ($)	Sep. 30, 2019 shares	May 31, 2019 USD ($)
BUSINESS COMBINATIONS
Common Stock, Shares, Issued \| shares			10,805,057			10,510,694
Payments to Acquire Businesses, Gross			$ 2,165	$ 684
Finance Lease, Liability, Payment, Due			4,766
Operating Lease, Payments			58
Revenues			12,918	8,625
Net loss			(1,426)	$ (85)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill							$ 2,595
Smithers Avanza Toxicology Services LLC acquisition
BUSINESS COMBINATIONS
Business Combination, Consideration Transferred		$ 2,595
Escrow Deposit Disbursements Related to Property Acquisition		$ 125
Common Stock, Shares, Issued \| shares		200
Payments to Acquire Businesses, Gross		$ 1,271
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable		$ 394
Class of Warrant or Right, Covenants Period		5 years
Revenues			2,695
Net loss			31
Smithers Avanza Toxicology Services LLC acquisition \| Promissory Note [Member]
BUSINESS COMBINATIONS
Debt Instrument, Face Amount		$ 810
Debt Instrument, Interest Rate, Effective Percentage		6.50%
PCRS acquisition
BUSINESS COMBINATIONS
Business Combination, Contingent Consideration, Asset	$ 5,857
Business Combination, Consideration Transferred	1,500
Payments for purchase of certain real property	$ 2,500
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned					$ 1,133
Business Acquisition, Transaction Costs			214
Revenues			381
Net loss			$ 66
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		$ 5,857
PCRS acquisition \| Unsecured promissory note
BUSINESS COMBINATIONS
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Debt Instrument, Face Amount	$ 800
Lease Arrangements [Member] \| Smithers Avanza Toxicology Services LLC acquisition
BUSINESS COMBINATIONS
Lessee, Operating Lease, Term of Contract		5 years 8 months
Number of Lease Extension Terms \| item		2
Lessee, Operating Lease, Renewal Term		5 years
Lease Arrangements [Member] \| Smithers Avanza Toxicology Services LLC acquisition \| Minimum
BUSINESS COMBINATIONS
Operating Lease, Payments		$ 400
Lease Arrangements [Member] \| Smithers Avanza Toxicology Services LLC acquisition \| Maximum
BUSINESS COMBINATIONS
Operating Lease, Payments		$ 600