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Summary of Significant Accounting Policies - Schedule of fair value on a recurring basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Fair Value, Inputs, Level 1 [Member] |  |
Assets: |  |
Money market funds | $ 1,010 | $ 16,775
Mutual funds | 15,841 | 14,264
Fair Value, Inputs, Level 2 [Member] |  |
Assets: |  |
Short-term investments | $ 104,870 | $ 74,510

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- Definition Fair value of money market funds. + References No definition available. + Details
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- Definition Mutual funds fair value disclosure. + 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 + Details
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- Details
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- Details
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- Details
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