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Summary of Significant Accounting Policies - Short-Term Investments (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
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Schedule of Held-to-maturity Securities [Line Items] |  |
Short-term investments | $ 8,500 | $ 14,675
Cash and Fixed Income Securities |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Short-term investments | $ 8,500 | $ 14,700

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- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity), classified as current. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26626-111562 + Details
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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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- Details
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