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Area of land held.

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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 item	Oct. 31, 2014	Dec. 31, 2015 USD ($) ft²	Dec. 31, 2014 USD ($)	Jun. 30, 2015 USD ($)
Leases
Operating lease agreement term	1 year	5 years
Rental square feet office space \| ft²			4,000
Number of operating lease annual renewal options \| item	2
Rent expense under operating lease			$ 143	$ 50
Annual future minimum lease payments
2016			232
2017			311
2018			318
2019			324
2020			330
Thereafter			139
Operating Leases, Future Minimum Payments Due, Total			1,654
Contractual Obligations
Remaining balance of purchase commitment			$ 2,800		$ 3,800
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 [Abstract]
Expiration period of obligation to pay royalties			10 years
Prepaid Expenses and Other Current Assets
Contractual Obligations
Balance of deposit for supplies			$ 1,000