Appointment of Chief Medical Officer (Details) - 2013 Long-Term Incentive Plan as Amended - Chief Medical Officer	1 Months Ended
Mar. 31, 2017 shares
Management Changes [Line Items]
Options granted (shares)	1,293,500
Term	7 years
Vesting period	4 years
Vesting percentage	25.00%
Cliff Vesting After One Year
Management Changes [Line Items]
Vesting period	1 year
Vesting Years Two Through Four
Management Changes [Line Items]
Vesting period	3 years

Management changes.

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Period of time over which stock options can be exercised, in years

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Gross number of share options (or share units) granted during the period.

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Percentage of vesting of share-based compensation awards.

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