Quarterly report pursuant to Section 13 or 15(d)

Organization and Summary of Significant Accounting Policies - Additional Information (Detail)

v3.10.0.1
Organization and Summary of Significant Accounting Policies - Additional Information (Detail)
3 Months Ended 6 Months Ended
Aug. 01, 2017
Jun. 30, 2018
USD ($)
Jun. 30, 2018
USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]      
Reverse stock split of common stock, description 11-for-1 reverse stock split    
Reverse stock split of common stock conversion ratio 11    
Takeda Pharmaceuticals Inc      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Accounts receivable   $ 663,000 $ 663,000
Revenue | Credit Risk      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Percentage of total revenues   68.00% 59.00%