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Summary Of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Jan. 01, 2018
New Accounting Pronouncement, Early Adoption [Line Items]
Restricted cash	$ 100		$ 100		$ 100
Advertising Expense	400	$ 400	1,100	$ 1,100
Revenue	10,439	8,223	30,173	22,799
Cumulative effect of changes in accounting principle related to revenue recognition						$ 3,086
ASU 606
New Accounting Pronouncement, Early Adoption [Line Items]
Cumulative effect of changes in accounting principle related to revenue recognition						$ 3,100
Janssen (SIMPONI)
New Accounting Pronouncement, Early Adoption [Line Items]
Revenue	431	0	835	0
Shipping and Handling
New Accounting Pronouncement, Early Adoption [Line Items]
Cost of revenue	400	$ 300	1,100	$ 900
Other assets
New Accounting Pronouncement, Early Adoption [Line Items]
Restricted cash	$ 100		$ 100
IPO
New Accounting Pronouncement, Early Adoption [Line Items]
Deferred Offering Costs					$ 400