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Commitments and Contingencies (Details) $ in Thousands	1 Months Ended		12 Months Ended
Commitments and Contingencies (Details) $ in Thousands	Nov. 30, 2015 ft² item	Oct. 31, 2014 ft²	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) ft²	Dec. 31, 2014 USD ($)
Leases
Operating lease agreement term	1 year	5 years
Rental square feet office space \| ft²	1,000	4,000
Number of operating lease annual renewal options \| item	2
Rent expense under operating lease			$ 322	$ 143	$ 50
Annual future minimum lease payments
2017			333
2018			318
2019			324
2020			330
2021			139
Total minimum lease payments			$ 1,444
Employee Benefit Plan
Maximum employees contribution (as a percent)			50.00%
Vesting period			4 years
Amended Lease
Leases
Operating lease agreement term			62 months
Rental square feet office space \| ft²				8,500
License Agreement \| Purdue Neuroscience Company
License agreement
Expiration period of obligation to pay royalties			10 years
Prepaid Expenses and Other Current Assets
Contractual Obligations
Balance of deposit for supplies				$ 1,000