FAIR VALUE - Schedule of Fair Value Hierarchy for Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Liabilities:
Contingent consideration, current portion	$ 7,200	$ 6,776
Contingent consideration	30,759	31,776
Recurring
Assets:
Total		77
Liabilities:
Contingent consideration, current portion	7,200	6,776
Contingent consideration	30,759	31,776
Total	37,959	38,552
Recurring \| Money market funds
Assets:
Investments		77
Recurring \| Level 1
Assets:
Total		77
Liabilities:
Contingent consideration, current portion	0	0
Contingent consideration	0	0
Total	0	0
Recurring \| Level 1 \| Money market funds
Assets:
Investments		77
Recurring \| Level 2
Assets:
Total		0
Liabilities:
Contingent consideration, current portion	0	0
Contingent consideration	0	0
Total	0	0
Recurring \| Level 2 \| Money market funds
Assets:
Investments		0
Recurring \| Level 3
Assets:
Total		0
Liabilities:
Contingent consideration, current portion	7,200	6,776
Contingent consideration	30,759	31,776
Total	$ 37,959	38,552
Recurring \| Level 3 \| Money market funds
Assets:
Investments		$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
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Sum of the carrying amounts as of the balance sheet date of all investments.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
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Fair value of financial and nonfinancial obligations.

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