XML 38 R29.htm IDEA: XBRL DOCUMENT v3.20.2
Significant Accounting Policies - Additional Information (Details) - USD ($)
Jun. 30, 2020
Dec. 31, 2019
Schedule Of Accounting Policies [Line Items]    
Restricted cash $ 182,000 $ 182,000
Potential interest and penalties associated with uncertain tax positions, accruals 0  
Letter of Credit    
Schedule Of Accounting Policies [Line Items]    
Restricted cash $ 182,000