v3.8.0.1
Accounts receivable, trade (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Accounts receivable $ 196 $ 315  
Allowance for doubtful accounts (196) (196)  
Accounts receivable, net 119  
Balance at the beginning of the year 196 1  
Addition 195 $ 1
Balance at the end of the period $ 196 $ 196 $ 1