Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accrued Liabilities, Current [Abstract]
Contract research costs	$ 13,775	$ 571
Compensation and benefits	2,779	1,797
Professional fees	1,177	1,062
Other	5,906	2,527
Total	$ 23,637	$ 5,957

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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