8. Accounts Receivable (Details - Accounts receivable) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current accounts receivable:
Accounts receivable	$ 28,410	$ 13,471
Less: Allowance for doubtful accounts	(633)	(1,520)
Net	27,777	11,951
Noncurrent accounts receivable
Accounts receivable, noncurrent	0	7,100
Total accounts receivable, net	$ 27,777	$ 19,051

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

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