Commitments and Contingencies (Details)		1 Months Ended	6 Months Ended	12 Months Ended
	May. 06, 2014 USD ($)	May. 31, 2010 $ / shares	Jun. 30, 2015 patients	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares shares	Aug. 21, 2014 USD ($)	Jul. 17, 2014 USD ($)	Sep. 17, 2013 USD ($)
Loss Contingencies [Line Items]
Deposits for clinical trial services				$ 4,176,280	$ 356,367
Nonrefundable and noncreditable maintenance fees				12 months
Discretionary cash bonus				$ 0	$ 0
Options, granted (in shares) | shares				1,843,000	547,117	862,287
Exercise option price (in usd per share) | $ / shares		$ 2.50		$ 0.54	$ 1.28	$ 2.67
Lease monthly rent				$ 8,063
Percentage of annual increase of monthly base rent				3.00%
Operating lease rent expense				$ 102,000	$ 99,000	$ 80,000
JHU
Loss Contingencies [Line Items]
Period within effective date of License Agreement				30 days
Employment Agreement With Management
Loss Contingencies [Line Items]
Base salary				$ 1,300,000
Discretionary cash bonus				$ 450,000
Options, granted (in shares) | shares				1,125,000	317,500	489,000
Exercise option price (in usd per share) | $ / shares				$ 0.58	$ 1.34	$ 2.66
Stock options, vesting period				4 years
Restricted shares issued by the company (in shares) | shares				260,000
Severance costs				$ 856,000
Novella Clinical
Loss Contingencies [Line Items]
Number of patients | patients			400
Deposits for clinical trial services				$ 3,725,722
Termination notice period				60 days
ICON
Loss Contingencies [Line Items]
Estimated payments for services							$ 3,500,000	$ 2,300,000	$ 2,700,000
Service fee, amendments and aggregate	$ 170,004