9. Stock Options (Details Narrative) - USD ($) $ in Thousands	1 Months Ended						12 Months Ended
	May 17, 2012	May 19, 2011	May 20, 2010	May 21, 2009	May 29, 2008	May 30, 2007	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 19, 2015
Option exercised							343,000	294,000
Options outstanding							1,035,000	975,000	1,235,000
Common Stock, Capital Shares Reserved for Future Issuance							1,081,000
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount							$ 1,023
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition							2 years 3 months 19 days
2005 Plan [Member]
Number of Shares Authorized	3,700,000	3,400,000	3,000,000	2,500,000		1,500,000	750,000
Number of Additional Shares Authorized	300,000	400,000	500,000	500,000	500,000	750,000
Option exercised							1,861,335
Options outstanding							526,000
Options grants							3,892,000
Options cancelled							1,504,665
Common Stock, Capital Shares Reserved for Future Issuance							0
2015 Plan [Member]
Number of Shares Authorized										600,000
Option exercised							45,000
Options outstanding							509,000
Options grants							557,000
Options cancelled							3,000
Common Stock, Capital Shares Reserved for Future Issuance							46,000