BeiGene Agreement (Details)	6 Months Ended
Jun. 30, 2018 USD ($)
Change in Contract with Customer Liability [Roll Forward]
Deferred revenue - current	$ 0
Additions	318,000
Deductions	0
Deferred revenue - current	318,000
Deferred revenue - non-current	0
Additions	215,000
Deductions	0
Deferred revenue - non-current	215,000
Total contract liabilities:	0.00
Additions	533,000
Deductions	0
Total contract liabilities:	$ 533,000

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Contract with Customer, Current Liability, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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