Commitments and Contingencies - Summary of Commitments and Contingencies (Detail)	Jun. 30, 2016 USD ($)
Commitment And Contingencies [Line Items]
Total	$ 12,033,000
2016	915,000
2017	3,291,000
2018	3,191,000
2019	2,957,000
2020	335,000
Thereafter	1,344,000
Ampion Supply Agreement [Member]
Commitment And Contingencies [Line Items]
Total	7,650,000
2017	2,550,000
2018	2,550,000
2019	2,550,000
Clinical Research and Trial Obligations [Member]
Commitment And Contingencies [Line Items]
Total	712,000
2016	602,000
2017	110,000
Sponsored Research Agreement With Related Party [Member]
Commitment And Contingencies [Line Items]
Total	894,000
2016	163,000
2017	325,000
2018	325,000
2019	81,000
Facility Lease [Member]
Commitment And Contingencies [Line Items]
Total	2,777,000
2016	150,000
2017	306,000
2018	316,000
2019	326,000
2020	335,000
Thereafter	$ 1,344,000