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Cash, Cash Equivalents and Short-Term Investments - Additional Information (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Cash, Cash Equivalents and Short-Term Investments |  |
Losses on available-for-sale investments | $ 32,400 | $ 81,700
Equity Securities, FV-NI | $ 33,100,000 | $ 26,000,000.0

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- Definition Amount of realized gain (loss) on investment in debt and equity securities. Excludes other-than-temporary impairment (OTTI). + References No definition available. + Details
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740 + Details
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