Commitments and Contingencies (Details) shares in Millions	Jun. 08, 2017 USD ($)	May 03, 2017 USD ($) shares	Mar. 13, 2017 item director	Jun. 30, 2017 USD ($)	Apr. 07, 2017 plaintiff	Mar. 03, 2017 item
Guarantor Obligations [Line Items]
Number of incumbent members commenced action | item						6
Total number of incumbent members | item						7
Number of plaintiff withdrew claims | plaintiff					3
VenBio Action [Member]
Guarantor Obligations [Line Items]
Reimbursement expense	$ 200,000
Number of nominees | item			4
Number of incumbent directors | director			3
Goldenberg and Sullivan
Guarantor Obligations [Line Items]
Arbitration cost incurred				$ 0
Goldenberg and Sullivan | Maximum
Guarantor Obligations [Line Items]
Arbitration cost incurred		$ 650,000
Restricted Units Vesting Based on Certain Market Conditions [Member] | Goldenberg Agreement [Member]
Guarantor Obligations [Line Items]
Restricted stock units granted | shares		1.5
Employment Agreement [Member] | Goldenberg Agreement [Member]
Guarantor Obligations [Line Items]
Total foregoing cash payments		$ 2,400,000
Employment Agreement [Member] | Sullivan Agreement [Member]
Guarantor Obligations [Line Items]
Total foregoing cash payments		3,100,000
Employment Agreement [Member] | Goldenberg and Sullivan
Guarantor Obligations [Line Items]
Arbitration cost incurred				$ 0
Employment Agreement [Member] | Goldenberg and Sullivan | Maximum
Guarantor Obligations [Line Items]
Arbitration cost incurred		$ 650,000