BUSINESS COMBINATIONS - Preliminary purchase price (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Smithers Avanza Toxicology Services LLC acquisition
Assets acquired and liabilities assumed:
Receivables	$ 1,128
Property and equipment	1,564
Prepaid expenses	147
Goodwill	545
Accrued expenses	(219)
Customer advances	(570)
Total	2,595
PCRS acquisition
Assets acquired and liabilities assumed:
Receivables	578
Property and equipment	2,666
Unbilled revenues	162
Prepaid expenses	27
Goodwill	3,002
Accounts payable	(109)
Accrued expenses	(118)
Customer advances	351
Total	$ 5,857

Amount of customer advances assumed.

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The amount of unbilled revenues recognized as of the acquisition date.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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