FAIR VALUE MEASUREMENT AND FINANCIAL INSTRUMENTS - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Significant Unobservable Inputs (Level 3)
Liabilities:
Contingent consideration - long term	$ 157,000
Recurring \| Quoted Prices in Active Markets (Level 1)
Assets:
Money market funds (cash equivalents)	16,377	$ 16,374
Liabilities:
Contingent consideration - short term	0	0
Contingent consideration - long term	0	0
Recurring \| Significant Other Observable Inputs (Level 2)
Assets:
Money market funds (cash equivalents)	0	0
Liabilities:
Contingent consideration - short term	0	0
Contingent consideration - long term	0	0
Recurring \| Significant Unobservable Inputs (Level 3)
Assets:
Money market funds (cash equivalents)	0	0
Liabilities:
Contingent consideration - short term	9,835	8,985
Contingent consideration - long term	147,165	99,855
Carrying Amount
Liabilities:
Contingent consideration - short term	9,835	8,985
Contingent consideration - long term	147,165	99,855
Carrying Amount \| Recurring
Assets:
Money market funds (cash equivalents)	16,377	16,374
Fair Value
Liabilities:
Contingent consideration - short term		8,985
Contingent consideration - long term		99,855
Fair Value \| Recurring
Assets:
Money market funds (cash equivalents)	16,377	16,374
Liabilities:
Contingent consideration - short term	9,835
Contingent consideration - long term	$ 147,165	$ 108,840

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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
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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