Significant Accounting Policies - Schedule of Assets Measured at Fair Value (Details) - Fair Value, Recurring Basis - Active Markets (Level 1) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total	$ 114,188	$ 167,896
Money Market Funds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash and cash equivalents	81,481	167,805
Restricted cash	91	$ 91
US Treasury Securities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments	22,861
Corporate Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments	$ 9,755

Cash and cash equivalents restricted cash fair value disclosure.

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- Definition

Restricted cash fair value disclosure.

+ References

No definition available.

+ Details

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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

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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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