14. STOCK-BASED COMPENSATION (Details - Stock based compensation expense) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Total stock-based compensation expense	$ 2,616	$ 2,019	$ 1,838
Employees [Member]
Total stock-based compensation expense	2,173	1,694	1,493
Non-Employees [Member]
Total stock-based compensation expense	$ 443	$ 325	$ 345