Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail)

v3.7.0.1
Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member]
$ in Thousands
Mar. 31, 2017
USD ($)
Assets  
Total assets $ 16,722
Warrant [Member]  
Liabilities  
Liabilities 180
Cash [Member]  
Assets  
Total assets 2,728
Money market securities (cash equivalents) [Member]  
Assets  
Total assets 12,962
Restricted cash [Member]  
Assets  
Total assets 272
Corporate bonds and commercial paper (short term investments) [Member]  
Assets  
Total assets 760
Level 1 [Member]  
Assets  
Total assets 15,962
Level 1 [Member] | Cash [Member]  
Assets  
Total assets 2,728
Level 1 [Member] | Money market securities (cash equivalents) [Member]  
Assets  
Total assets 12,962
Level 1 [Member] | Restricted cash [Member]  
Assets  
Total assets 272
Level 2 [Member]  
Assets  
Total assets 760
Level 2 [Member] | Corporate bonds and commercial paper (short term investments) [Member]  
Assets  
Total assets 760
Level 3 [Member] | Warrant [Member]  
Liabilities  
Liabilities $ 180