XML 54 R43.htm IDEA: XBRL DOCUMENT v3.21.2
Revenues and Trade Receivables, Net, Trade and other receivables, net (Details) - USD ($)
$ in Thousands
Sep. 30, 2021
Dec. 31, 2020
Dec. 31, 2019
Revenues and Trade Receivables, Net [Abstract]      
Trade receivables $ 11,500 $ 4,330  
Contract and other receivables 2,637 3,081  
Less: allowance for doubtful accounts (40) (40) $ (124)
Less: sales-related allowances (454) (416)  
Trade and other receivables, net $ 13,643 $ 6,955