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Commitments - License agreements (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
License Agreement, Upfront Payments |  |  |
Research and Development Arrangement, Contract to Perform for Others [Line Items] |  |  |
Research and development expense | $ 3,075 | $ 250 | $ 750
License Agreement, Milestone Payments |  |  |
Research and Development Arrangement, Contract to Perform for Others [Line Items] |  |  |
Research and development expense | $ 2,125 | $ 750 | $ 600

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- Definition The amount of costs incurred under a research and development arrangement accounted for as a contract to perform research and development for others. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23221-108380 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23199-108380 + 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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