Business Combination - Acquisition-related Activities Expense (Details) - SVB Leerink - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Business Acquisition [Line Items]
Professional fees	$ 283	$ 651
Other	69	273
Total acquisition-related expenses	$ 352	$ 924

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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