Restructuring Liabilities - Narrative (Details)	1 Months Ended
Feb. 28, 2017 position
Research and Development Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, 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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