Nature of Business and Accounting Policies - Restructuring Expenses (Details)	12 Months Ended
Dec. 31, 2019 position
Research and development restructuring
Restructuring Cost and Reserve [Line Items]
Number of positions eliminated	70

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Period Type:	duration