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Significant Accounting Policies, Cash, Cash Equivalents and Investments (Details) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended
--- | --- | --- | ---
Sep. 30, 2020 USD ($) Company | Jun. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Jun. 30, 2020 Investment | Sep. 30, 2020 USD ($) Company | Sep. 30, 2019 USD ($)
Cash, Cash Equivalents and Investments [Abstract] |  |  |  |  |  |
Number of publicly held companies in which there is an equity ownership interest of less than 20% | Company | 2 |  |  |  | 2 |
Number of privately held companies in which there is an equity ownership interest of less than 20% | Company | 5 |  |  |  | 5 |
Number of investments in privately held companies that were revalued | Investment |  |  |  | 2 |  |
Gain on investment | $ 835 |  | $ 0 |  | $ 10,722 | $ 0
Dynacure SAS [Member] |  |  |  |  |  |
Cash, Cash Equivalents and Investments [Abstract] |  |  |  |  |  |
Gain on investment |  | $ 6,300 |  |  |  |
Ribo [Member] |  |  |  |  |  |
Cash, Cash Equivalents and Investments [Abstract] |  |  |  |  |  |
Gain on investment |  | $ 3,000 |  |  |  |

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- Definition Number of publicly-held companies, in which the entity has an equity ownership interest of less than 20%, with which it conducts business. These are accounted for at fair value. + References No definition available. + Details
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- Definition Amount of realized and unrealized gain (loss) on investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27405-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(c),9(a)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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