BeiGene Exclusive Option and License Agreement - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Jan. 03, 2020
BeiGene Exclusive Option and License Agreement
Up-front fee		$ 3,000
Contract acquisition costs	$ 270	270
Amortization expense	34	101
Deferred Costs	169	169
Exclusive Option and License Agreement
BeiGene Exclusive Option and License Agreement
Upfront cash payment	3,000	3,000	$ 3,000
Future option exercise and milestone payments, maximum			$ 132,000
License
BeiGene Exclusive Option and License Agreement
Revenue recognized	375	1,125
Royalty
BeiGene Exclusive Option and License Agreement
Revenue recognized	$ 0	$ 0

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