Collaborative and Licensing Arrangements - Details of Proceeds From Transaction (Details) - Amgen, Inc - USD ($) $ in Thousands		12 Months Ended
Jan. 02, 2020	Dec. 31, 2020
Research and Development Arrangement, Contract to Perform for Others
Fair value of equity issued to Amgen	$ 2,162,407	$ 2,162,407
Fair value of research and development cost share liability	$ 616,834	616,834
Total cash proceeds		$ 2,779,241

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3213-108585

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