8. Accounts Receivable (Tables)

12 Months Ended

Dec. 31, 2018

Receivables [Abstract]

Schedule of accounts receivable

The accounts receivable as of December 31, 2018 and 2017 consisted of the following: 

	December 31,			December 31,
	2018			2017
Current accounts receivable:
Accounts receivable	$	28,410		$	13,471
Less: Allowance for doubtful accounts		(633	)		(1,520	)
		27,777			11,951
Noncurrent accounts receivable
Accounts receivable, noncurrent		–			7,100
Total accounts receivable, net	$	27,777		$	19,051

Allowance for doubtful accounts rollforward

	2018			2017			2016
Balance as at January 1	$	1,520		$	1,592		$	211
Addition		202			1,536			1,151
Written off		–			(1,526	)		–
Reversal		(1,002	)		(152	)		–
Foreign currency translation difference		(87	)		70			230
Balance as at December 31	$	633		$	1,520		$	1,592