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Commitments and Contingencies (Details) - USD ($)			3 Months Ended		9 Months Ended
Commitments and Contingencies (Details) - USD ($)	Jan. 09, 2017	May 02, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Oct. 19, 2015	Apr. 02, 2012
Commitments and Contingencies [Line Items]
Payments to HPI over three-year period		$ 750,000.00
Buy-out option payment to HPI		$ 1,000,000.0
HPI Out-Licensing Agreement term		3 years
Sponsored Laboratory Study Agreement expense			$ 1,061,000	$ 497,000	$ 2,260,000	$ 616,000
Commencement of Phase II Study for a licensed product
Commitments and Contingencies [Line Items]
Milestone payments liabilities							$ 200,000
Commencement Of Phase III Study For a Licensed Product
Commitments and Contingencies [Line Items]
Milestone payments liabilities							250,000
Filing of a New Drug Application for a licensed product
Commitments and Contingencies [Line Items]
Milestone payments liabilities							400,000
Receipt of market approval for a licensed product
Commitments and Contingencies [Line Items]
Milestone payments liabilities							500,000
Commencement Of Phase III Study For First Licensed Product
Commitments and Contingencies [Line Items]
Milestone payments liabilities							150,000
Submission Of First NDA Within United States
Commitments and Contingencies [Line Items]
Milestone payments liabilities							500,000
Receipt Of First Market Approval For Sale of A Licensed Product
Commitments and Contingencies [Line Items]
Milestone payments liabilities							$ 600,000
MD Anderson
Commitments and Contingencies [Line Items]
Sponsored Laboratory Study Agreement expense	$ 302,500
Servicing Fee payable \| Patent and Technology License Agreement
Commitments and Contingencies [Line Items]
Annual maintenance fee, first anniversary								$ 10,000
Annual maintenance fee, second anniversary								20,000
Annual maintenance fee, third anniversary								40,000
Annual maintenance fee, fourth anniversary								60,000
Annual maintenance fee, fifth anniversary								80,000
Annual maintenance fee, sixth anniversary								100,000
Annual royalty payment, third anniversary								600,000
Minimum Annual Royalty \| Patent and Technology License Agreement
Commitments and Contingencies [Line Items]
Annual royalty payment, first anniversary								200,000
Annual royalty payment, second anniversary								$ 400,000