FAIR VALUE MEASUREMENT OF FINANCIAL INSTRUMENTS - Summary of Assets and Liabilities Measured at Fair Value (Details) - Recurring Fair Value Measurements $ in Thousands	Dec. 31, 2019 USD ($)
Assets:
Short-term investments	$ 57,044
Cash and cash equivalents	355,010
Investments	19,087
Other current assets	35,618
Other assets	3,687
Total assets measured at fair value	470,446
Liabilities:
Contingent earnout liability	19,873
Level 1
Assets:
Short-term investments	27,423
Cash and cash equivalents	355,010
Investments	18,794
Other current assets	35,618
Other assets	3,687
Total assets measured at fair value	440,532
Liabilities:
Contingent earnout liability	0
Level 2
Assets:
Short-term investments	29,621
Cash and cash equivalents	0
Investments	293
Other current assets	0
Other assets	0
Total assets measured at fair value	29,914
Liabilities:
Contingent earnout liability	0
Level 3
Assets:
Short-term investments	0
Cash and cash equivalents	0
Investments	0
Other current assets	0
Other assets	0
Total assets measured at fair value	0
Liabilities:
Contingent earnout liability	19,873
Certificates of deposit
Assets:
Short-term investments	6,643
Certificates of deposit \| Level 1
Assets:
Short-term investments	0
Certificates of deposit \| Level 2
Assets:
Short-term investments	6,643
Certificates of deposit \| Level 3
Assets:
Short-term investments	0
Corporate and municipal debt securities
Assets:
Short-term investments	22,978
Corporate and municipal debt securities \| Level 1
Assets:
Short-term investments	0
Corporate and municipal debt securities \| Level 2
Assets:
Short-term investments	22,978
Corporate and municipal debt securities \| Level 3
Assets:
Short-term investments	0
U.S. government and federal agency securities
Assets:
Short-term investments	27,423
U.S. government and federal agency securities \| Level 1
Assets:
Short-term investments	27,423
U.S. government and federal agency securities \| Level 2
Assets:
Short-term investments	0
U.S. government and federal agency securities \| Level 3
Assets:
Short-term investments	$ 0

Fair value portion of other noncurrent assets.

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Represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with fair value disclosures required in footnote disclosures to financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This element represents the fair value of assets categorized as other current assets which are not in and of themselves material enough to require separate disclosure.

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Fair value portion of short-term investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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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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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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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.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Publisher FASB
-Name Accounting Standards Codification
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