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)

v3.10.0.1
Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member]
$ in Thousands
Sep. 30, 2018
USD ($)
Assets  
Total assets $ 13,195
Cash [Member]  
Assets  
Total assets 2,936
Money market securities (cash equivalents) [Member]  
Assets  
Total assets 8,819
Restricted cash [Member]  
Assets  
Total assets 50
Corporate bonds and commercial paper (short term investments) [Member]  
Assets  
Total assets 1,390
Level 1 [Member]  
Assets  
Total assets 11,805
Level 1 [Member] | Cash [Member]  
Assets  
Total assets 2,936
Level 1 [Member] | Money market securities (cash equivalents) [Member]  
Assets  
Total assets 8,819
Level 1 [Member] | Restricted cash [Member]  
Assets  
Total assets 50
Level 2 [Member]  
Assets  
Total assets 1,390
Level 2 [Member] | Corporate bonds and commercial paper (short term investments) [Member]  
Assets  
Total assets $ 1,390