Note 9 - Income Taxes - Schedule of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Carry forward losses and credits	$ 7,407	$ 6,294
Deferred revenues	14,226	16,774
Accrued payroll, commissions, vacation	1,105	2,078
Allowance for doubtful accounts	633	43
Accrued severance pay	239	372
Other	2,668	2,939
Net deferred tax assets before valuation allowance	26,278	28,500
Valuation allowance	(26,122)	(28,500)
Net deferred tax assets	$ 156