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)

v3.8.0.1
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, 2018
USD ($)
Assets  
Total assets $ 4,437
Cash [Member]  
Assets  
Total assets 1,133
Money market securities (cash equivalents) [Member]  
Assets  
Total assets 3,032
Restricted cash [Member]  
Assets  
Total assets 272
Level 1 [Member]  
Assets  
Total assets 4,437
Level 1 [Member] | Cash [Member]  
Assets  
Total assets 1,133
Level 1 [Member] | Money market securities (cash equivalents) [Member]  
Assets  
Total assets 3,032
Level 1 [Member] | Restricted cash [Member]  
Assets  
Total assets $ 272