Business Combination - Acquisition-related Activities Expense (Details) - SVB Leerink $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Business Acquisition [Line Items]
Professional fees	$ 368
Other	204
Total acquisition-related expenses	$ 572

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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-Name Accounting Standards Codification
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