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Fair Value Measurements - Schedule of Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash equivalents	$ 9,810	$ 31,676
Short-term investments	75,099	61,615
Assets measured at fair value	84,909	93,291
Money Market Funds
Current assets:
Cash equivalents	9,810	15,677
Corporate Debt Securities
Current assets:
Cash equivalents		2,500
Short-term investments	9,034	11,588
Commercial Paper
Current assets:
Cash equivalents		13,499
Short-term investments	64,044	50,027
U.S. Treasury Notes
Current assets:
Short-term investments	2,021
Level 1
Current assets:
Cash equivalents	9,810	15,677
Assets measured at fair value	9,810	15,677
Level 1 | Money Market Funds
Current assets:
Cash equivalents	9,810	15,677
Level 2
Current assets:
Cash equivalents		15,999
Short-term investments	75,099	61,615
Assets measured at fair value	75,099	77,614
Level 2 | Corporate Debt Securities
Current assets:
Cash equivalents		2,500
Short-term investments	9,034	11,588
Level 2 | Commercial Paper
Current assets:
Cash equivalents		13,499
Short-term investments	64,044	$ 50,027
Level 2 | U.S. Treasury Notes
Current assets:
Short-term investments	$ 2,021

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Short-term investment fair value disclosure.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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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