Annual report pursuant to Section 13 and 15(d)

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

v3.20.4
Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($)
$ in Thousands
Dec. 31, 2020
Dec. 31, 2019
Assets    
Total assets $ 35,903 $ 16,714
Cash [Member]    
Assets    
Total assets 473 949
Money market securities (cash equivalents) [Member]    
Assets    
Total assets 35,380 15,715
Restricted cash [Member]    
Assets    
Total assets 50 50
Level 1 [Member]    
Assets    
Total assets 35,903 16,714
Level 1 [Member] | Cash [Member]    
Assets    
Total assets 473 949
Level 1 [Member] | Money market securities (cash equivalents) [Member]    
Assets    
Total assets 35,380 15,715
Level 1 [Member] | Restricted cash [Member]    
Assets    
Total assets $ 50 $ 50