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Significant Accounting Policies, Cash, Cash Equivalents and Investments (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 USD ($) Company | Mar. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) Investment
Cash, Cash Equivalents and Investments [Abstract] |  |  |
Number of publicly held companies in which there is an equity ownership interest of less than 20% | Company | 3 |  |
Number of privately held companies in which there is an equity ownership interest of less than 20% | Company | 7 |  |
Number of investments in privately held companies that were revalued | Investment |  |  | 3
Gain on investments | $ | $ (6,625) | $ 0 |
Investments in Dynacure, Suzhou-Ribo and Aro Biotherapeutics [Member] |  |  |
Cash, Cash Equivalents and Investments [Abstract] |  |  |
Gain on investments | $ |  |  | $ 14,800

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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=123581744&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=123367319&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=123570139&loc=d3e3602-108585 + Details
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