Collaborative Arrangement (Details) - USD ($) $ in Thousands	1 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Accounts receivable	$ 15,500	$ 0
Contract liability	15,500
Remaining amount to be billed in accordance with terms of agreement	4,500
Deferred revenue, current	5,000	$ 0
Fixed Consideration
Disaggregation of Revenue [Line Items]
Performance obligation at inception of arrangement	20,000
Accounts receivable	$ 15,500
Payment term	2 years
Variable Consideration \| Achievement of Regulatory Milestones
Disaggregation of Revenue [Line Items]
Amount that can be earned upon achievement of milestone	$ 66,000
Variable Consideration \| Achievement of Net Sales Milestones
Disaggregation of Revenue [Line Items]
Amount that can be earned upon achievement of net sales milestone	$ 42,500

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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